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Education and Training
Epidemiology & Prevention of Vaccine-Preventable Diseases Broadcast
Questions & Answers
Questions submitted during the Epidemiology & Prevention of Vaccine-Preventable Diseases broadcasts January & February, 2007

Questions and Answers image

General Recommendations

  1. Why are the products respiratory syncytial virus IGIV and VZIG no longer on Table 4 of the ACIP General Recommendations?

    These products are no longer listed because they are no longer made. Fortunately the monoclonal antibody product RSV IG is available and is still on Table 4, and VariZIG, an investigational product used for post-exposure prophylaxis for varicella, is included in a footnote to Table 4.

  2. Should a person receiving Synagis delay receipt of live virus vaccines?

    No. Synagis is a monoclonal immune globulin product to protect against respiratory syncytial virus (RSV). It does not contain any antibodies other than RSV, so there is no reason to delay receipt of live virus vaccines.

  3. Do Tdap and MCV4 need to be spaced one month apart if not given simultaneously?

    Certain experts recommend spacing these vaccines by a month if not given simultaneously. This is out of a theoretical safety concern of giving two vaccines containing diphtheria antigen (MCV4 contains diphtheria antigen) in close temporal proximity. However, ACIP feels that this theoretical safety concern does not warrant spacing, and recommends that these two inactivated vaccines can be administered simultaneously or non-simultaneously without a need for an interval between them.

  4. Do you recommend documenting the amount of vaccine on the provider’s Vaccine Administration Record?

    This is not required by law; the National Childhood Vaccine Injury Act, and laws establishing publicly purchased vaccine, require chart documentation only of the date of administration of the vaccine, the date of the VIS, the vaccine manufacturer, the lot number, and the name/address/title of the person administering the vaccine.

  5. When new ACIP recommendations are published, do we need to keep the old ones?

    For most vaccine-specific ACIP recommendations this should be self-explanatory or explained in the summary statement. For example, the 2006 General Recommendations build upon the 2002 recommendations, so the 2002 recommendations are no longer needed. Updates that supplement, but do not replace, prior ACIP recommendations are sometimes published as a "Notice to Readers" in the weekly MMWR.

  6. If a child with sickle cell disease who receive blood transfusions every month received the first transfusion less than two weeks after their vaccines, when can the vaccinations be repeated?

    This is a challenge with the live vaccines. Measles and varicella containing vaccines are not valid when given at a short interval. A replacement dose of these vaccines would need to be spaced at an interval which can range from zero to seven months following the product, depending on the amount of antibody in the product. Table 4 in the ACIP General Recommendations on Immunization lists these specific intervals.

  7. If a child with sickle cell is taking hydroxyurea, do they need to defer live vaccines?

    Hydroxyurea is an antineoplastic agent that is used for some cancers as well as sickle cell disease. It inhibits DNA synthesis and therefore should be considered in the same category as antimetabolites. Defer live vaccines for 3 months following therapy.

  8. Is there a table of commercially licensed vaccine brand names and what vaccines they contain?

    The Pink Book, available online at, contains this information. See Appendix B.

  9. If we administer a vaccine dose with a minimum interval of 28 days, and we observe the grace period, this results in an interval of 24 days. Is this acceptable?

    Yes, if your state recognizes the grace period. Also, if you use the grace period, be sure it is for a good reason. For example, if a child is in your office for some other reason, and you are concerned that he or she will not come back for an immunization visit, don't miss the opportunity to vaccinate. But do not schedule patients routinely using the grace period.

    Also, do NOT apply the grace period to the 28 day interval between two different live vaccines not administered on the same day, e.g., MMR and varicella. It should be applied only to intervals between doses of the same vaccine.

  10. If a patient faints following vaccination, should we submit a VAERS report.

    Yes, after medical attention has been given to the vaccine recipient. Any occurrence of medical significance that is not an accepted adverse reaction warrants a VAERS report.

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Vaccine Storage and Handling

  1. Is it okay to store vaccines in a cooler with ice packs for several hours and then return the vaccines to the refrigerator at the end of the day?

    We don’t encourage this practice but sometimes it is necessary if you need to move vaccines to an off-site clinic. You must make sure the vaccine is properly packed and place a certified calibrated thermometer within. The temperature should be monitored and recorded hourly. Be conservative and try to get this vaccine into a refrigerator at the destination site if at all possible. A frozen vaccine like varicella can be stored at refrigeration temperature for seventy-two hours but must be discarded if not used within that time. You cannot put varicella vaccine back in the freezer after it has been at refrigerator temperature. The Vaccine Storage & Handling Toolkit offers guidance on “Transporting Vaccine to Off-Site Clinics,” (pages 6-9).

  2. If a dose of expired vaccine is administered, does it need to be repeated? How soon can the dose be repeated?

    Doses of expired vaccines are invalid and should be repeated. For an inactivated vaccine you can give the repeat dose ASAP. With a live vaccine there could be some vaccine viral replication that would interfere with a subsequent dose, so you should wait 28 days before giving the repeat dose.

  3. Please define "frozen" and "freezing" regarding vaccines. Vaccine Providers are often under the impression that "frozen" means only solid state or the formation of ice crystals. I perform AFIX visits routinely and would like to be able to inform the providers correctly as to what is meant specifically by "freezing temperatures."

    We recently published temperature ranges in the General Recommendations on Immunization Table 9, page 12. (This link goes to an MMWR weekly that published a corrected version of Table 9.) For inactivated vaccines the appropriate temperature range is 35-46° F. Refrigerator temperatures below 35° should prompt concern. Often one cannot see the effects of vaccine stored too cold or too hot.

  4. Are MMR and varicella vaccines effective if stored in the refrigerator for 72 hours after reconstitution?

    No. MMR vaccine must be used within 8 hours of reconstitution and varicella vaccine must be used within 30 minutes of reconstitution.

  5. Once opened, how long may a multidose vial of vaccine be used?

    A multidose vial can be used until the expiration date as long as it is stored and handled properly and is normal in appearance, unless otherwise stated by the vaccine manufacturer. Always consult the manufacturer’s package information that accompanies the vaccine.

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Vaccine Administration

  1. Is there evidence for the use of alcohol to clean the administration site prior to injecting a vaccine?

    ACIP has not directly addressed this issue. If alcohol is used, wait a few seconds to let the alcohol dry before you inject vaccine.

  2. If a vaccine is inadvertently administered by the wrong route, should the dose be repeated, and if so, when?

    Subcutaneous vaccines given by the intramuscular route need not be repeated. Intramuscular vaccines given by the subcutaneous route usually do not need to be repeated (exceptions: Hepatitis B vaccine given by any route other than intramuscular, rabies vaccine given in the gluteus). Incorrect routes other than intramuscular or
    subcutaneous generally should be repeated. An invalid vaccine dose of a live vaccine should be repeated after four weeks. An invalid dose of an inactivated vaccine may be repeated immediately.

  3. Would you use one site for more than one vaccine if there were other sites available? For example, using two vaccines in the deltoid of a child, as opposed to using one leg.

    Use separate sites if possible. Which site(s) to use can depend on the age of the vaccine recipient. The preferred site for children two years old and younger is the anterolateral thigh. The preferred site for children three years old and older is the deltoid. The size of the muscle mass also is relevant for intramuscular injections, as well as availability of certain sites (e.g. a cast may make the anterolateral thigh inaccessible). If you must use the same site for two vaccinations, you should space them at least one inch apart.

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  1. Why are so many vaccines recommended at the same time? If an allergic reaction occurs, how would you know which vaccine caused it?

    Vaccines are recommended at the age for which there is a risk of disease. For many vaccine-preventable diseases, the greatest risk is in infancy and the early years of life. These diseases are still out there, so the decision to vaccinate is one of risk versus benefit; it is still very important to prevent these diseases.

    It is difficult to pinpoint which vaccine may have caused an anaphylactic reaction that occurred following multiple vaccinations; but fortunately, anaphylaxis following vaccination is rare. We are currently working on protocols for follow-up assessment and vaccination of persons who have suffered an allergic reaction following vaccination, protocols that involve giving one vaccine at a time.

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Diphtheria, Tetanus, Pertussis

  1. If someone has received Boostrix and then sustains a wound, what vaccine would you give?

    You should follow the tetanus wound protocol and give Td if indicated. Boostrix and Adacel are licensed for a one-time dose. If someone has not received Boostrix or Adacel, sustains a wound, and tetanus prophylaxis is indicated, then either Boostrix or Adacel can be used, depending on the age of the recipient.

  2. A 7-year-old received DT as an infant due to a seizure incident, unrelated to vaccines or epilepsy. No further seizures occurred; no medication was necessary. Can this child receive Tdap when age appropriate?

    Yes, a history of infant seizures occurring within 72 hours following vaccination is a precaution for further doses of infant DTaP, but because seizures are not associated with Tdap, history of infant seizures are neither a precaution nor a contraindication to Tdap. The child should receive Tdap when age appropriate.

  3. If a 60-year-old patient presents for a Td booster without prior vaccine history, can you offer Tdap?

    Yes, you can and should offer Tdap. This is an off-label recommendation by CDC (because the vaccine is licensed as a booster). Since this person has no documented history of tetanus and diphtheria vaccination, follow the Tdap one month later with a Td dose and 6 months later with another Td dose.

  4. In the first case study, why did the 8-year-old girl not need a Td? She had a DTaP combination at 2, 3, 4, and 18 months, but no booster at 4-6 years. We give DTaP at 2, 4, 6, and 15 months and then a booster at 4-6 years. Doesn’t she need a Td booster now?

    Some experts recommend a dose of Td at this point (see Appendix E of, Adolescent Tdap recommendations). The childhood/adolescent schedule recommends a dose of Td now as well. However, others feel that the fifth dose of tetanus-containing vaccine is driven by the need for pertussis protection; this protection is not available for children age seven years through nine years. Therefore, our recommendation (if someone receives the first dose of tetanus-containing vaccine at younger than 12 months and then receives four total doses) is a dose of tetanus-containing vaccine is not needed until the child is eleven years old. Of course,if the child sustains a dirty wound in the interim, she would need a dose of Td ASAP.

  5. If a child completes the primary DTaP series on schedule and then receives a Td booster prior to age 11 years, when is a Tdap dose due - 5 years from the Td they received, or 10 years?

    An adolescent should receive a dose of Tdap five years from the last dose of Td.

  6. Would you please explain reported hyperimmune responses to tetanus vaccination?

    A reaction known as an Arthus reaction rarely occurs following multiple doses of tetanus-toxoid or diphtheria-toxoid containing vaccine given at short intervals. This reaction is due to circulating antigen-antibody complexes. It is characterized by pain and redness that can extend from shoulder to elbow. Sometimes there is a necrotic center. The reaction is severe but self-limited. For people who have experienced an Arthus reaction we recommend giving all subsequent tetanus- or diphtheria-containing vaccine doses at intervals no shorter than ten years.

  7. If an adult had pertussis as a child, does she need Tdap in adulthood?

    Infection with pertussis does not confer lifelong immunity. Adults with a history of pertussis generally should receive Tdap according to the routine recommendations.

  8. How effective is Tdap when given to an adult who has not received a primary series of DTP or DTaP?

    There are no clinical data on this situation because this population was not included in the Tdap clinical trials. Tdap is FDA approved as a one-time booster dose. However, ACIP feels that one dose is better than no doses and, thus, made the off-label recommendation. Future data will provide evidence on the effectiveness of this dose.

  9. We have an immunization record on a 6-year-old boy from Mexico. The child has been given a total of 7 DTaP doses. His last dose was given at the age of 3, two months before his 4th birthday. Should the 5th dose be repeated since the child was not 4 years of age when he received it?

    The general guideline is to avoid administering more than 6 doses of DTaP before 7 years of age. This child likely has adequate protection against all 3 antigens. However, if school law requires a dose on or after the 4th birthday, then this dose can be repeated. The child’s parents should be cautioned that the child may experience an exaggerated local reaction, but this is transient.

  10. Is a history of DTP or DTaP vaccination needed prior to administering Tdap to all adults or only adults who need the vaccine for immigration, to complete the primary series, or for school?

    A history of DTP or DTaP is not a requirement for receiving Tdap. The package insert indicates Tdap as a booster dose following a primary series of pertussis-containing vaccine. However, CDC makes the off-label recommendation that Tdap may be used as one dose of the primary series (for anybody).

  11. If a 61-year-old received a Td booster one year ago, when should he receive Tdap?

    The recommended interval is 10 years after the last Td booster. However, if there is a pertussis outbreak or this person has contact with an infant younger than 12 months of age, there is no minimum interval. The need for pertussis protection outweighs the risk of a sore arm.

  12. If DTaP was given to an adult instead of Tdap, should the Tdap dose still be given, and if so, at what interval?

    Do not give the Tdap dose. This person has received the appropriate amount of tetanus toxoid and MORE diphtheria toxoid and pertussis antigen than is recommended. Count the dose, but take measures to prevent this error in the future. A VAERS report should also be submitted on any vaccine administration error.

  13. If a child completes the pediatric DT schedule at 15 months of age, when would the next tetanus dose be due?

    If pertussis is not contraindicated, the child should receive a dose of Tdap at 11 years of age.

  14. What it the minimum interval between Td and Tdap for healthcare personnel who work with children?

    An interval as short as 2 years from the last dose of Td is suggested to reduce the risk of local and systemic reactions; but a shorter interval may be used. There is no absolute minimum interval.

  15. Is it preferable to give Td or Tdap during pregnancy?

    ACIP and AAP have different recommendations on the use of Tdap in pregnancy.

    ACIP voted to recommend Td (not Tdap) during pregnancy if the woman is due for a routine tetanus booster. If she is not due for the routine booster (i.e., the previous Td booster was given within the preceding 10 years), the mother should receive Tdap immediately postpartum. However there are situations when a clinician can consider the use of Tdap for a pregnant woman, such as if there is a risk of exposure because of a pertussis outbreak. Tdap is not contraindicated for pregnant women. The infant's other household contacts ages 10 through 64 years should also receive 1 dose of Tdap, if not already given.

    AAP has endorsed preferential use of the Tdap vaccine during pregnancy in adolescents who were not vaccinated at the visit at age 11-12 years (Pediatrics 2006; 117:965-78). Providers can follow either the AAP or ACIP recommendation.

  16. If a pregnant woman receives Td during pregnancy, how soon can she receive a dose of Tdap?

    She should receive a dose of Tdap during the postpartum period, preferably before hospital discharge.

  17. Should a public health nurse who is 66 years old and working with infants receive Tdap?

    No. There is no Tdap vaccine that is FDA-approved or ACIP-recommended for use in anyone older than 64 years of age.

  18. Why can’t Adacel be administered to persons older than 64 years?

    There are no safety and efficacy data for this age group and FDA did not approve the vaccine for anyone older than 64 years of age.

  19. Why can’t we give a Tdap booster every 10 years?

    The current Tdap vaccines are FDA-approved for only one dose.

  20. Is it acceptable to administer Tdap to a 25-year-old healthcare worker who had physician diagnosed pertussis (not lab diagnosed) within the last 5 months?

    Yes, especially if the healthcare provider works with children. You should not consider withholding a dose of Tdap because of disease history, unless you have culture-confirmed disease within the last 5-10 years. Shorter intervals (shorter than 2 years from last tetanus-toxoid-containing vaccine) can be used with healthcare providers. You must use Adacel for anyone 19 through 64 years of age.

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Pneumococcal Conjugate

  1. If Menactra is given to an infant instead of pneumococcal conjugate vaccine, what do I do?

    Menactra is not licensed for infants so of course this dose is invalid. It does not provide any protection from Pneumococcus, so you need to give a dose of Pneumococcal conjugate vaccine. This can be given immediately, with no need for spacing, because Menactra and pneumococcal conjugate vaccine are two separate inactivated vaccines.

  2. With increasing pneumococcal conjugate vaccine coverage and increasing non-vaccine serotypes present, are there concerns about increased rates of antimicrobial resistance in these non-vaccine serotypes?

    This is an issue that bears watching. Surveillance is ongoing not only with the serotypes included the vaccine, but also others that are prevalent. Vaccine manufacturers are working on development of pneumococcal conjugate vaccines that will protect against additional serotypes; and some vaccine serotypes offer cross-protection against more than one disease serotype.

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Measles, Mumps, Rubella

  1. If a mother is nursing her child at 12 months, will a dose of MMR still be effective?

    Yes. Live vaccines like MMR are affected by circulating antibody from blood products or maternally transferred antibody during pregnancy. However, the antibody in breast milk is a different type than maternally transferred antibody or blood products (IgA versus IgG) so that breast feeding does not compromise the efficacy of live vaccines.

  2. Is there any indication that a person with idiopathic thrombocytopenia purpura should not get a second MMR?

    A history of thrombocytopenia is a precaution for either dose of MMR vaccine. The benefit of preventing the adverse reaction thrombocytopenia by withholding the vaccine is potentially outweighed by the fact that thrombocytopenia also can occur as a complication of measles or rubella disease, and this could be worrisome in someone with a previous history of thrombocytopenia. It is prudent to withhold a dose of MMR from a patient with thrombocytopenia that occurred within 6 weeks of a previous dose of MMR.

  3. Do you have any suggestions on responding to a parent who requests separate antigens (MMR) to avoid the vaccine made from an aborted fetus?

    Helping these patients understand the origin and nature of fetal tissue used in vaccine cultures might reduce their discomfort about receiving MMR.

    The rubella vaccine virus (used in MMR and single-antigen rubella vaccine) is cultured in human cell-line cultures, and some of these cell lines originated from aborted fetal tissue, obtained from legal abortions in the 1960's. No new fetal tissue is needed to produce cell lines to make these vaccines, now or in the future. Fetal tissue is not used to produce vaccines; cell lines generated from a single fetal tissue source are used; vaccine manufacturers obtain human cell lines from FDA-certified cell banks. After processing, very little, if any, of that tissue remains in the vaccine.

  4. Should an international traveler born before 1957 who thinks s/he had measles and mumps as a child be advised to get an MMR before traveling abroad?

    We recommend that you consider a dose of MMR for persons born before 1957 if they are traveling to an area where measles is common and the only evidence of immunity is their birthdate. Seroprevalence studies in healthcare workers show that up to 5% of persons born before 1957 ARE susceptible. Five percent susceptible is probably OK for adults at low risk of exposure, but it is NOT OK for persons at high risk of exposure, such as international travelers to areas with measles. You should consult a travel medicine specialist to determine your specific risk

  5. What should be done for a pregnant woman whose serology shows that she is not immune to Rubella (never had the disease or the vaccine)?

    You cannot vaccinate her while she is pregnant. Just advise her to be very careful about exposure during pregnancy. She should receive a dose of MMR postpartum before discharge from the hospital, (page 17).

  6. We did serology testing on a healthcare worker and the results were negative. However, the healthcare worker brought in a vaccination record with 2 MMRs documented. We did not vaccinate, but we did ask the employee to sign a declination form. Was this the correct action? Would the recommendation for Rubella be different if the healthcare worker works in an OB-GYN outpatient clinic or in a planned parenthood setting?

    If a healthcare worker has a record of two age-appropriate doses of MMR vaccine, no additional doses are needed in either situation. The criteria for immunity have been met.

  7. It was stated at a CDC conference that MMR is light sensitive. Does this sensitivity occur only before reconstitution or both before and after? Would this light sensitivity also be true for Varicella and MMRV?

    HPV, MMR, MMRV, rotavirus, varicella, and zoster vaccines are sensitive to light, which causes loss of potency. These vaccines must be protected from light at all times. Therefore, store these vaccines at the appropriate temperatures in their boxes with the tops on until they are needed.

  8. Are there ramifications if providers are vaccinating with the 2nd MMR at the minimum interval instead of waiting until the child is 4-6 years old?

    The minimum interval between MMR-1 and MMR-2 is 28 days. As long as the doses meet minimum age and minimum intervals, the child is considered to be biologically protected. However, you should make sure this is acceptable under your state's immunization entry school law. If not, the state may invalidate MMR-2 and require a dose on or after the 4th birthday.

  9. If we have a measles or mumps outbreak and have unvaccinated students in school, how long after they receive their first MMR could they be considered immune and allowed to return to school? How about after their second MMR?

    According to our surveillance manual, a person can be readmitted as soon as the first dose is given. (page 16) (page 10)

  10. Should healthcare personnel be required to have serologic evidence of immunity for measles if they have documentation of receiving two doses of vaccine?

    Documentation of two valid doses of live-virus measles vaccine is acceptable evidence of immunity and post-vaccination serologic testing is not recommended, (page 11, Table 1).

  11. Are there fewer side effects with MMR-2 due to immunity?

    Yes. The side effects are related to replication of vaccine virus. Most persons (90%-95%) are immune after dose one, thus fewer side effects are reported after dose two.

  12. Is it preferable to freeze or refrigerate MMR? If it is stored in the freezer, how long can the vaccine last outside the freezer?

    Unreconstituted MMR vaccine can be stored either in the freezer or the refrigerator. It can be stored in the refrigerator until its expiration date as long as the refrigerator temperature is 35° to 46° F, the vaccine is normal in appearance, and it is protected from light. Once reconstituted, the vaccine must be discarded if not used within 8 hours.

  13. Does someone born before 1957 who works in a day care center need MMR vaccine?

    Employees in a day care setting are not considered a high-risk group for MMR vaccination. Someone born before 1957 meets the birthdate critierion for immunity (except for rubella immunity for child-bearing women).

  14. Can an infant whose mother had an anaphylactic reaction to MMR be vaccinated?

    A family history of an allergic reaction is not a contraindication to vaccination.

  15. Can a person donate blood after receiving an MMR?

    Yes. Red Cross guidelines advise waiting four weeks after receipt of MMR before donating blood,,1082,0_557_,00.html#imm.

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  1. Since VZIG is no longer produced, what are the current options for an immunocompromised individual or a pregnant woman with no known immunity who is exposed to varicella?

    There is an investigational new product known as VariZIG that can be used for immunocompromised individuals or for pregnant women. Remember, this is a concern if the individual is susceptible to chickenpox. Instructions on the use of VariZIG are available in MMWR 2006; 55:209-210. VariZIG must be given within the first 96 hours following exposure. For immunocompromised persons, if this product cannot be obtained, IGIV can be administered – also within 96 hours. If a pregnant woman cannot receive VariZIG within 96 hours, she can be administered IGIV or can be followed for signs of rash and treated with acyclovir if a rash appears.

  2. Can varicella vaccine be used for post-exposure prophylaxis with children younger than 12 months of age? If not, would varicella immune globulin or an anti-viral be indicated?

    Varicella vaccine is neither recommended nor approved by FDA for use in children younger than 12 months. Post-exposure prophylaxis using varicella immune globulin (VariZIG) would only be indicated in this situation if the child were immunocompromised. Please see for instructions on how to obtain and use VariZIG.

    Anti-varicella anti-virals are used for treatment, not post-exposure prophylaxis. In this situation, if symptoms were to develop, anti-virals could be used if the patient is immunocompromised, on long-term salicylate therapy (including aspirin), or has a chronic skin or pulmonary disorder.

  3. Our state requires children born after January 1, 1997 to have a dose of varicella vaccine before attending school. If the parent verbally reports that the child has had chickenpox disease, we do not administer the vaccine. What if the parent is not reliable and what if it wasn't chickenpox that the child had? Should we continue to accept the parents word, despite the number of chickenpox disease outbreaks that we are seeing now.

    We recommend that you apply the revised definitions of varicella immunity, Note that we no longer recommend regarding parental reporting alone as reliable evidence of immunity.
    1. Documentation of age-appropriate vaccination: a. Preschool-aged children >12 months of age: one dose b. School-aged children, adolescents, and adults: two doses.
    2. Laboratory evidence of immunity (reliable for disease-induced immunity, but may yield false-negative results for vaccine-induced immunity) or laboratory confirmation of disease.
    3. Born in the US before 1980 (does not apply to pregnant women or healthcare personnel).
    4. A healthcare provider diagnosis of varicella or healthcare provider verification of history of varicella disease (Verification means that a healthcare provider may retrospectively diagnose chickenpox based on the history provided by a patient or parent. Verification of history or diagnosis of typical disease can be done by any healthcare provider [e.g., school or occupational clinic nurse, nurse practitioner, physician assistant, physician]. For people reporting a history of or presenting with atypical and/or mild cases, assessment by a physician or their designee is recommended and one of the following should be sought: a) an epidemiologic link to a typical varicella case or b) evidence of laboratory confirmation, if laboratory testing was performed at the time of acute disease. When such documentation is lacking, people should not be considered as having a valid history of disease, because other diseases may mimic mild atypical varicella.)
    5. History of herpes zoster based on healthcare provider diagnosis.
    When in doubt, vaccinate. The vaccine will not harm someone who is already immune.

  4. Does an infant younger than one year of age who has lab-verified chickenpox need varicella vaccine after the first birthday?

    No. Laboratory confirmation of disease, regardless of age at the time, is acceptable evidence of immunity.

  5. Could a fever of 102° or greater 42 days after varicella vaccine really be related to the vaccine? That seems like a very long time.

    Obviously there are many things that could be related to a fever of 102° or greater, but it is possible that it could be related to vaccination.

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Measles, Mumps, Rubella, Varicella (MMRV)

  1. Why is the interval between doses of MMRV vaccine three months instead of one month? The interval between doses of MMR is one month.

    Much of it has to do with data from clinical trials. MMRV was studied at three month intervals. Licensure is based on the intervals used in these prelicensure trials.

  2. Why can we not give MMRV to people with HIV/AIDS if the monovalent MMR and varicella vaccines can be given in some cases?

    The use of MMRV was not studied in patients with HIV/AIDS and the titer of varicella virus in MMRV is more than seven times as high as in monovalent varicella vaccine. So FDA did not license MMRV for patients with HIV/AIDS.

  3. Does a child who developes a mild rash, i.e. vesicles, following MMRV, need to be isolated?

    If a child developes vesicles following MMRV, it could be a vaccine associated rash, it could be breakthrough varicella, or it could be something else entirely. You should use your clinical judgment regarding the type and number of lesions to make this diagnosis. Most vaccine-associated lesions are maculopapular. If the diagnosis is breakthrough disease, treat this like wild-type varicella. Vaccine recipients in this situation should restrict contact with immunosuppressed persons who are susceptible to varicella.

  4. If MMRV is inadvertently administered to a healthcare professional do either or both vaccines need to be repeated or should titers be drawn?

    We recommend that you count the dose. Do not draw titers, but do assess your system to find out what measures can be taken to prevent a recurrence of this medication administration error. We also request that a VAERS report be submitted for all medication errors even when there is no adverse event.

  5. If MMRV-2 is given one or two months after MMRV-1, is MMRV-2 invalid and should it be repeated?

    The minimum interval between MMRV-1 and MMRV-2 is 3 months. However, if on record review you discover that MMRV-2 was given less than 3 months after MMRV-1, it can be counted and does not need to be repeated as long as there was an interval of at least 4 weeks between the two doses. This 4-week interval should NOT be used for forecasting or scheduling MMRV-2 doses. It should ONLY be used for record review evaluation of doses ALREADY administered.

  6. Why is MMRV not given to persons older than 12 years of age?

    Because the manufacturer did not request licensure and did not present safety and efficacy data on the use of MMRV in persons 13 years of age or older. The vaccine is not FDA approved for use in anyone younger than 12 months of age or older than 12 years of age.

  7. If two doses of MMRV are given at 3-month intervals, but both doses are given before 4 years of age, is a dose required at school entry?

    Another dose is not required unless your state will not accept a 2nd dose administered before 4 years of age. As long as both doses are administered after 12 months of age and are 3 months apart, the person is considered to be biologically protected.

  8. Does MMRV need to be delayed following receipt of Rhogam?

    First, MMRV should not be administered to anyone 13 years of age or older. If a post-partum woman is susceptible to measles, mumps, rubella, or varicella, then MMR and/or varicella vaccines should be administered before discharge from the hospital or birthing center. The woman should be tested for antibodies 3 months later. If she has not responded, she should be revaccinated as indicated.

  9. Why does MMRV contain so much more varicella vaccine virus than varicella vaccine?

    More varicella antigen was necessary to induce an immune response when the varicella vaccine virus was combined with measles, mumps, and rubella vaccine viruses, compared with the response when monovalent Var is administered alone or simultaneously with MMR.

  10. If varicella vaccine can be kept in the refrigerator for 72 hours and MMR vaccine can be stored in the refrigerator, why can’t MMRV be stored in the refrigerator?

    There is a lot more varicella vaccine virus in MMRV than in single-antigen varicella vaccine. The manufacturer storage data does not demonstrate adequate viability of the vaccine viruses in MMRV when stored at refrigerator temperatures.

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  1. Is a booster required for Menactra?

    No. We expect one dose of Menactra to provide life-long immunity. As the vaccine has been in use for only two years, we are still in the process of verifying this, but most conjugate vaccines produce long-term immunity.

  2. Does the incidence of Guillain Barré Syndrome (GBS) increase when Menactra and influenza vaccines are administered at the same time?

    There are no data to indicate an increased risk of GBS when Menactra and influenza vaccines are administered at the same time.

  3. Is there a vaccine that is given in other countries that is effective against meningococcal type B? If there is, why is it not available in the US?

    There are numerous sub-strains of Neisseria meningitidis type B. Vaccines produced in other countries for their indigenous strains would not necessarily be effective against the strains found in the United States. Efforts are being made to produce a U.S.-specific vaccine.

  4. What should I do if meningococcal conjugate vaccine was inadvertently administered to a 55-year-old or older person?

    Count the dose and do not revaccinate. Although the vaccine is not FDA approved for use in anyone older than 54 years, we have no reason to think that the person would not respond. However, this is a medication error that should not be repeated.

  5. Because MCV4 contains diphtheria toxoid, should we recommend that Td or Tdap and MCV4 be given on separate days, or may they be given at the same time?

    ACIP recommends that Td or Tdap and MCV4 can be administered in separate syringes at separate anatomical sites on the same day or at any interval from each other,

  6. If an 18-year-old presents for meningococcal vaccine with a history of a reaction to diphtheria toxoid, should we administer MPSV4 instead of MCV4?

    It depends on the reaction. If it was an anaphylactic type reaction, then give MPSV4. If it was an Arthus reaction and at least 10 years have elapsed, you can give MCV4.

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  1. Can zoster vaccine be administered with other vaccines? The package insert says that administration with other vaccines has not been studied.

    Zoster vaccine would be administered most often with inactivated influenza vaccine and pneumococcal polysaccharide vaccines (also inactivated). Applying guidelines from ACIP's General Recommendations, an interval is not required between an inactivated vaccine and a live vaccine.

  2. A sixty-one-year old male presents with an unknown history of varicella illness. His wife is currently diagnosed with shingles. He is asymptomatic. Does he need both the varicella vaccine as well as the zoster vaccine?

    The wife's current illness is irrelevant to the decision to vaccinate the husband. Persons born in the U.S. before 1980 can be assumed to be immune to varicella and can receive zoster vaccine if at least 60 years of age with no medical contraindications to the vaccine.

  3. If you have a severe case of chickenpox, does this predispose you to an increased risk of shingles?

    There is no information indicating that the severity of chickenpox has any effect on the chances of getting zoster (shingles) later in life. If a person has had chickenpox, the virus is present and logically the chances of it becoming reactivated and causing zoster would be the same whether the disease was mild or severe. Having had chickenpox at a very early age does seem to predispose the person more to zoster. The reasons are not clear.

  4. Does a dose of zoster vaccine need to be repeated if administered by the intramuscular route instead of the subQ route?

    No. Vaccines should always be given by the route recommended by the manufacturer because data regarding safety and efficacy of alternate routes are limited. If a dose of vaccine is inadvertently given by the wrong route, ACIP recommends that it be counted as valid. There are two exceptions to this recommendation: hepatitis B or rabies vaccine given by any route other than IM should not be counted as valid and should be repeated (, pages 18-19).

  5. Is zoster vaccine indicated for persons with no history of varicella disease?

    In conducting routine zoster vaccination of persons 60 years of age or older, there is no need to verbally screen for varicella history (i.e., inquire about the person's history of varicella) or to conduct laboratory testing for serologic evidence of prior varicella. If the person is 60 years of age or older and has no medical contraindications, s/he is eligible for zoster vaccine.

  6. Can someone with shingles infect a susceptible person with varicella?

    Yes. Shingles itself cannot be passed from one person to another. However, the virus that causes shingles, VZV, can be spread from a person with active shingles to a person who has never had chickenpox through direct contact with the rash. The person exposed would develop chickenpox, not shingles. The virus is not spread through sneezing, coughing or casual contact. A person with shingles can spread the disease when the rash is in the blister-phase. Once the rash has developed crusts, the person is no longer contagious. A person is not infectious before blisters appear or during a period of post-herpetic neuralgia (pain after the rash is gone).

  7. What is the interval between receiving zoster vaccine and donating blood?

    The general guideline is to wait at least 4 weeks after vaccination with varicella vaccine to donate blood. However, you should contact the Red Cross for specific guidance for zoster vaccine,,1082,0_557_,00.html#imm.

  8. Shingles is known to occur in persons younger than 60 years of age. Can zoster vaccine be given to them?

    Not at this time. Zoster vaccine is only FDA approved for use in persons 60 years of age and older, and there are no ACIP off-label recommendations to use this vaccine in anyone younger than 60 years old.

  9. When thinking about giving herpes zoster vaccine to a person 60 years of age or older, how soon after a case of shingles can the vaccine be given?

    The general guideline for any vaccine is to wait until the acute stage of the illness is over and symptoms abate.

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Hepatitis A

  1. What if we violate the minimum 6 month interval between Hepatitis A doses by more than four days?

    The second dose would be invalid, and should be repeated after an interval of at least 6 months. A single dose of Hepatitis A vaccine is 95-97 percent immunogenic, so it is protective in the short term. The second dose is important to provide long-term immunity.

  2. Can Hepatitis A vaccine be administered after a hematapoietic stem cell transplant?

    This should not be a problem, since Hepatitis A is an inactivated vaccine. There are very little data on giving repeat doses of this vaccine following HSCT, since it has only recently become universally recommended. It makes sense to give this vaccine with the other inactivated vaccines, 12 months post-transplant.

  3. Since the two doses of hepatitis A vaccine need to be separated by 6 months, and one month equals four weeks, can we separate doses by 24 weeks?

    No. For periods of four months or longer, we recommend using calendar months for spacing, rather than converting to weeks. The rationale: because most months are longer than four weeks, using this conversion introduces error that progressively shortens the interval. For example, with 4 weeks equaling a month, 12 months would be only 336 days or almost a month short of a year. Therefore we prefer you use calendar months for the Hepatitis A interval.

  4. How do you complete the hepatitis A and heptatis B series with single-antigen vaccines if the patient started with Twinrix, and vice versa?

    Because the hepatitis B component of Twinrix is equivalent to a standard, adult, dose of hepatitis B vaccine, the schedule is the same whether Twinrix or single-antigen hepatitis B vaccine is used.

    Single-antigen hepatitis A vaccine may be used to complete a series begun with Twinrix and vice versa. A person 19 years of age or older who receives one dose of Twinrix may complete the hepatitis A series with two doses of adult formulation hepatitis A vaccine separated by at least 5 months. A person who receives two doses of Twinrix may complete the hepatitis A series with one dose of adult formulation hepatitis A vaccine or Twinrix 5 months after the second dose. A person who begins the hepatitis A series with single-antigen hepatitis A vaccine may complete the series with two doses of Twinrix or one dose of adult formulation hepatitis A vaccine.

  5. The second dose of hepatitis A vaccine was administered 4 months after the first dose. A repeat dose was given 4 months after the invalid second dose. What should we do now?

    Nothing. We do not recommend a fourth dose of hepatitis A vaccine in this situation. Response to one dose is 95% or better. There is no reason to think this person does not have adequate protection.

  6. Should hepatitis A vaccine be given to sewage workers?

    No. Sewage workers are not at increased risk for hepatitis A infection because of their occupation. Persons who are at increased risk for HAV infection include:
    • travelers to countries that have high or intermediate endemicity of HAV infection (for map of endemic areas, see
    • men who have sex with men (MSM)
    • users of injection and noninjection illegal drugs
    • persons with clotting-factor disorders
    • persons working with nonhuman primates

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Hepatitis B

  1. If a health care worker received three doses of hepatitis B vaccine in childhood and recently received two additional doses, should we do a titer now or should we just give the third dose before performing the titer?

    You can do a titer now. If the childhood series produced immunity, the first of the two recent doses should have generated a detectable antibody level. If the test is positive, you do not need to give more doses; if the test is negative, you should give another dose and then test for antibody at least one month but no later than 2 months later.

  2. Should we vaccinate someone with hepatitis B vaccine if they have a diagnosis of hepatitis B disease?

    Someone diagnosed with hepatitis B does not need to be vaccinated, as they are already infected and therefore immune. But they should be counseled about the risks of transmission, and will require follow up therapy to monitor for progression of disease.

  3. If a child receives a birth dose of Hepatitis B vaccine, and then Pediarix at 2 months and 8 months, does there need to be an eight week interval between the 2 and 3 dose of Pediarix?

    You need to make sure that the minimum spacing intervals are observed for every antigen in the vaccine (except for those for which the series is already complete). In this specific case, the child is already complete for Hepatitis B and is late for the 3rd dose of DTaP and Hib. Since the minimum interval for dose 2 and dose 3 of Pediarix (per the package insert) is six weeks, six weeks would seem to be an acceptable interval in this situation.

  4. If we are using a routine schedule for Hepatitis B vaccine for adults – 0, 1 month and 6 months – what happens if someone falls behind? Let’s say they receive the second dose 3 months after the first. When should they return for dose three?

    If an adult is receiving Hepatitis B vaccine it means that he or she might be at risk, and one could argue that minimum intervals should be used to expedite vaccine doses if someone falls behind in the schedule (presumably because of a missed clinic visit). So give the third dose eight weeks after dose number two in this situation.

  5. What is the interval between the first two doses of Hepatitis B vaccine?

    The recommended interval is variable by age and allows for several different schedules; it is important to remember that the minimum interval between dose 1 and dose 2 is four weeks.

  6. I'm using the catch-up schedule for HBV for a 15-year-old. I gave dose one on January 8th and scheduled dose 2 for February 5th (28 days later). Mom called wanting him to get dose 2 on February 1st. Would this be considered 4 or 5 days before February 5th?

    We would consider February 1st four days before February 5th. February 4th would be one day before February 5th, February 3rd two days, etc. So by that logic February 1st would be four days. Be sure your state accepts the Grace Period

  7. If a police officer was previously vaccinated for Hepatitis B and while patting down a suspect he is stuck with a needle, should he have his antibody level checked? Should he start immune globulin? Should he be tested 6 months later?

    If the police officer is a known vaccine responder or if the source of the exposure is known to be HBsAg-negative, no treatment for Hepatitis B is necessary. However, if the police officer was a known vaccine nonresponder or if his immune response is unknown, then the treatment depends on the HBsAg status of the source. If a program is in place to implement testing and follow-up algorithms, the hepatitis B post-exposure prophylaxis protocol should be followed,

  8. If 5 years have elapsed since hepatitis B dose-2, should the series be restarted?

    No. There are no maximum intervals between doses; just pick up where the person left off and complete the series.

  9. When hepatitis B vaccine and HBIG are administered to a newborn, should the doses be given in separate extremities?

    It is preferable to use separate extremities. If this is not possible, the two IM injections should be separated by at least one inch. This may be challenging in a newborn thigh.

  10. We have a new healthcare employee who needs hepatitis B protection. She has 3 documented doses of hepatitis B vaccine from several years ago, but she cannot remember if she had serologic testing after the series. How should we proceed?

    If the third dose of vaccine was administered prior to 1997, you should consider someone with three documented age-appropriate doses of vaccine as immune. In 1997 we began to recommend post-vaccination testing. If the third dose was administered in 1997 or later, first, check with the former employer to find out if there is a record of post-vaccination serologic testing. Is the following true? I thought we test, if negative give three doses, and then test. If there is not, there are two options: 1) One is to repeat the 3-dose series, testing for anti-HBs after the third dose. 2) A probably less expensive option is to administer a single dose of vaccine and test in 4-6 weeks. If the person is anti-HBs antibody positive, this most likely indicates a booster response
    in a previous responder, and no further vaccination (or serologic testing) is needed. If the person is anti-HBs antibody negative after this “booster” dose, a second series should be completed (i.e., two more doses). If the person is still seronegative after six total doses, he or she should be managed as a nonresponder. (10th Edition Pink Book page 229)

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Human Papillomavirus

  1. What are the minimum intervals for the Human Papillomavirus vaccine?

    The minimum intervals for HPV vaccine are: 4 weeks between dose 1 and dose 2, and twelve weeks between dose 2 and dose 3. You can finish the entire series in sixteen weeks, and no faster. The only place this is currently written is in the Vaccines for Children HPV vaccine web page which reflects the ACIP recommendations for this vaccine.

  2. My review of the literature indicates that the vaccine is 95% effective after a single injection. Is the CDC reviewing the possibility of changing to a single injection and is there discussion of booster requirements?

    The data that led to licensure of HPV vaccine was based on three doses. ACIP will only recommend the vaccine to be used in the manner in which it was approved by FDA (3 doses). There are no data on which to base a recommendation for fewer than 3 doses. Duration of immunity studies are in progress.

  3. Can the HPV vaccine be given to those with HIV?

    Because quadrivalent HPV vaccine is a noninfectious vaccine, it can be administered to females who are immunosuppressed as a result of disease or medications. However, the immune response and vaccine efficacy might be less than that in persons who are immunocompetent, (page 18).

  4. Is there an indication for women older than 26 who are high risk?

    HPV vaccine is not approved or recommended for women older than 26 years.

  5. Is HPV vaccine being tested for use in males?

    Efficacy studies among males are in progress. At this time HPV vaccine is not approved or recommended for males of any age.

  6. Is the age range for HPV vaccine 9 years to 26 years or 9 years through 26 years?

    The approved age range for HPV vaccine is 9 years THROUGH 26 years (i.e., to the 27th birthday). We do not recommend use of this vaccine outside the age range approved by the Food and Drug Administration.

  7. How long does protection from the Human Papillomavirus (HPV) vaccine last? Is a booster required?

    The vaccine is too new to know how long protection will last. There are no booster doses recommended at this time. Studies will continue to assess the duration of effectiveness.

  8. Is it appropriate to administer HPV vaccine to a female who states she is gay?

    HPV vaccine is approved for all females 9 years through 26 years of age. Sexual orientation is not a factor.

  9. Our physician has written a standing order to give HPV vaccine to all adolescent males and females in our practice. Is this appropriate?

    HPV vaccine is only approved for use in females 9 years through 26 years of age. The vaccine is not approved for use in males.

  10. Should we do pregnancy testing before administering HPV vaccine?

    Routine pregnancy testing of women of childbearing age before administering a vaccine is not recommended. Ask if the female could be pregnant or is planning to become pregnant while receiving the vaccine series. If the response is no, vaccinate and explain in terms the patient can understand why it is important to avoid pregnancy until 4 weeks after the series is complete. We do suggest that you consider asking what form of birth control is being used. Some sexually active females will say they could not be pregnant, yet are not using birth control.

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Pneumococcal Polysaccharide

  1. Is PPV recommended for persons with diabetes?

    Yes, diabetes increases the risk for invasive disease from pneumococcus. One dose of PPV vaccine should be administered to persons 2 years and older with diabetes.

  2. What is the recommendation regarding a second dose of PPV in a situation where the risk is continuing (e.g., sickle cell disease)? Should the patient receive the second dose 5 years after the first? That would mean that, if the patient is a child, a considerable amount of time may elapse after the second dose without another booster. Would you suggest a longer interval in this situation?

    The recommended interval between doses of PPV is 3 years if the child is seven years old or younger at the time of the first dose. Otherwise, the interval is 5 years. No more than two lifetime doses of PPV are recommended, regardless of the age the doses are received. Children 59 months and younger should also receive pneumococcal conjugate vaccine as age-appropriate.

  3. If a person younger than 65 years of age has already received 2 doses of PPV, should a 3rd dose be given after age 65 if 5 years have passed since the last dose?

    No. There are no recommendations to administer more than 2 doses of PPV in a lifetime.

  4. Should you wait a specified time after a splenectomy to vaccinate with PPV?

    Ideally, PPV should be administered at least two weeks before a scheduled splenectomy. If this is not possible, then the patient can be vaccinated when stable at hospital discharge.

  5. Some physicians in our area order PPV every 5 years for their patients. Is this correct?

    ACIP does not recommend more than one or two doses of PPV vaccine in a lifetime. PPV is a polysaccharide vaccine that does not boost well and data do not indicate that multiple doses are beneficial.

  6. Should persons with chronic disease who receive PPV vaccine be revaccinated?

    Persons with chronic disease (heart, lung, metabolic, etc.) should receive one dose of PPV vaccine. If that dose is administered before 65 years of age, then a second dose should be given after 65 years of age as long as 5 years have elapsed since the first dose.

  7. If a person received a dose of PPV at 65 years of age and then is treated for cancer at 75 years of age, would a second dose of PPV be indicated?

    Yes. This person would be immunocompromised and a second dose would be indicated,

  8. Should someone who has received a cochlear implant receive one or two doses of PPV?

    One dose of PPV is indicated for someone who has had a cochlear implant. This is not an indication for revaccination.

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  1. If someone receives live attenuated influenza vaccine, do they need to wait 4 weeks before becoming pregnant?

    Live attenuated influenza vaccine is contraindicated in pregnancy. Neither the manufacturer nor ACIP has recommended a minimum interval between vaccination and pregnancy, but because the duration of replication is similar to that of MMR and varicella viruses, it seems reasonable to follow the general rule for live vaccines and avoid pregnancy for four weeks.

  2. If we run out of the thimerosal-free Flu vaccine for children younger than 3 years of age, can the thimerosal-containing vaccine be used?

    Yes, if this is all you have available and as long as the age-appropriate dose is administered (0.25 mL for children 6 months through 35 months of age). The known risks to young children from complications of influenza infection outweigh any theoretical risk from the very small amount of thimerosal in the vaccine. NOTE: If using prefilled syringes with 0.5 mL, the unused portion of the vaccine should be discarded.

  3. We have told patients they cannot get an allergy shot on the same day as a vaccine and must wait 24 hours between them. I was told if there were a reaction you would not be able to tell if it was from the vaccine or the allergy shot. The problem comes during flu season when we have a large number of patients coming in for allergy shots and influenza vaccination. What do you advise?

    The probability of a serious allergic reaction following any vaccine is extremely low if the person is properly screened. The ACIP has no recommendation for this situation, but has never recommended that desensitization injections and vaccines be separated by any specific time period.

  4. What year did inactivated influenza vaccine (TIV) become available?

    Trivalent inactivated influenza vaccine has been available since the 1940s.

  5. Can LAIV be used to treat influenza?

    There are no recommendations to use influenza vaccine for treatment.

  6. If a child receives influenza vaccine at 34 or 35 months of age for the first time (dose 0.25mL) and the child returns for the second dose at 37 months (3 years) of age, should the child receive 0.25 mL or 0.5 mL?

    The child should receive the dose appropriate for his or her age at the time of the clinic visit; for a 37-month-old child that would be 0.5 mL.

  7. In the case of an influenza outbreak and a vaccine shortage, is it an effective strategy to vaccinate previously unvaccinated children with only one dose so there are more doses to go around?

    If a child presents at the clinic for dose 2, the child should be vaccinated. There are no recommendations to withhold adequate vaccination from some to offer inadequate vaccination to many. For influenza naïve children younger than 9 years of age, one dose of vaccine primes the immune system, but offers little or no protection. It is the second dose to which these children will respond with an adequate immune response.

  8. Can LAIV be given as early as 12 months of age in light of the new recommendations?

    No. There are no new recommendations regarding age indications for LAIV. LAIV can only be used for healthy, nonpregnant persons 5 years through 49 years of age.

  9. If someone has had influenza, should they receive influenza vaccine?

    Yes. There are two commonly circulating serotypes of influenza A and one circulating serotype of influenza B. Someone with a history of influenza disease is still vulnerable to the other two serotypes. The vaccine is matched and protects against all three.

  10. If influenza activity increases in February or March, should second doses of influenza vaccine be considered for high-risk groups?

    No. Only one dose of influenza vaccine is recommended annually except for children 6 months through 8 years of age who are receiving influenza vaccine for the first time.

  11. What is the minimum interval between the two doses of influenza vaccine for children who require two doses?

    If the child receives two doses of TIV, the minimum interval between the two doses is 4 weeks.
    If the child receives two doses of LAIV (only healthy children 5 years through 8 years of age), the minimum interval is 6 weeks.
    If the child receives one dose of TIV and one dose of LAIV, it depends on which dose is administered first. If the child receives TIV first, wait 4 weeks to administer LAIV. If LAIV is given first, wait 6 weeks to administer TIV.

  12. Can a flu shot be given at anytime during pregnancy or should we wait until the second trimester?

    Pregnant women can receive inactivated influenza vaccine (TIV) regardless of the stage of pregnancy.

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Haemophilus influenzae type b

  1. Which Hib vaccine would you recommend for an adult who has had a splenectomy?

    ACIP does not specify any brand of Hib vaccine for this purpose. These persons can receive one pediatric dose of any single-antigen Hib vaccine.

  2. A 28-year-old female with asplenia received Hib vaccine 5 years ago. Should she now receive a booster dose?

    There are no recommendations to give Hib booster doses in this situation.

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  1. Is a baby eligible for RotaTeq #1 at 12 weeks and 1-6 days or is the cut off 12 weeks and 0 days? Also the same question for 32 weeks, please.

    An infant should not receive the first dose of rotavirus vaccine once s/he is 13 weeks of age. An infant should not receive any rotavirus vaccine once s/he is 33 weeks of age.

  2. Is rotavirus vaccine contraindicated for a child who had surgery for intestinal blockage when younger than 12 weeks of age?

    This is a risk/benefit situation that should be evaluated on an individual basis by the healthcare provider. For further information, please review the contraindication/precaution section of the ACIP recommendations, at (pages 8-9).

  3. Is it OK to give rotavirus vaccine to a child who is 13 weeks + 4 days of age?

    No. This vaccine is not approved or recommended for use in children 13 weeks of age or older.

  4. If an infant received rotavirus vaccine at 16 weeks of age and is not yet 24 weeks of age, do you count the first dose and continue with the vaccine series?

    Infants for whom the first dose of rotavirus vaccine was inadvertently administered off label at 13 weeks of age or older may receive the remaining two doses of the series at the routine intervals. Timing of the first dose should not affect the safety and efficacy of the second and third dose. The third dose should not be given after 32 weeks, however.

  5. Can rotavirus vaccine be given to a child who has had surgery for intestinal blockage?

    This is an individual risk/benefit decision that must be made by the child’s healthcare provider.

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  1. What is the recommendation for adults who have had polio vaccine but have no record of it and now need to show proof for college?

    Polio vaccine is not recommended for adults unless they are traveling to a polio endemic or epidemic country. If the college insists, then the adult needs to follow the rules of the college and show evidence of immunity or documentation of vaccination.

  2. When one adult dose of polio is recommended for travel, how does this apply to older travelers who were already adults when they got their primary series in the 1950's or 1960's? Is the recommendation always for only one adult dose or is there ever a time limit for people who have had an adult dose of polio but it was many years ago?

    Adult travelers who have already completed a primary series need one additional dose for travel, regardless of their age when they got their prior doses. If the primary series is unfinished they should finish the primary series.

  3. We see exclusively refugees in our clinic who come from Africa, eastern European countries, Middle Eastern countries. They frequently come with no documentation of any vaccinations. Is a complete IPV series recommended for adults from these countries?

    If they plan to travel back to a country with endemic polio or epidemic polio, they should receive a primary series.

  4. We see many children from other countries. Many have been given the first polio at birth to one week of age.
    1. What is the minimum acceptable age for the first polio dose?
    2. Does a child who received four doses of OPV need a dose of IPV?

    The minimum acceptable age for a dose of OPV or IPV is 6 weeks, (Table 1 - page 3).
    Four doses of OPV or IPV in any combination by age 4–6 years is considered a complete series,
    IF your state law requires a dose on or after the 4th birthday and the child's documented polio immunization history does not meet that requirement, then you can give a dose of IPV to meet the school requirement.

  5. If a person who has had polio disease travels to a polio endemic country, does s/he need polio vaccine?

    Yes. Polio infection only offers immunity to the serotype with which the person was infected. Polio vaccine protects against 3 serotypes of polio virus. The person should receive age-appropriate vaccination is traveling to a polio endemic area of the world.

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  1. If serologic testing is so unreliable, why is there so much reference to doing it in the latest ACIP recommendations?

    If you are referring to the General Recommendations on Immunization, we have added limited guidance on the use of serology in situations where the results of false-negatives (common with serology) do not impact negatively, and the cost of giving additional doses may be high. Examples include:
    1) the decision to perform serology instead of vaccinating someone with unknown records (e.g. measles, rubella, hepatitis A, tetanus)
    2) performing serology when thousands of people have received improperly stored vaccine (wrong temperature) (i.e. MMR, Var, MMRV). Notice that if the serology is negative, you give a dose anyway.

    It all comes down to the cost-benefit of performing the test instead of giving the vaccine. Because the tests do have high false-negative rates, we do not recommend their use routinely for persons who have documented evidence of vaccine doses. This comes into play often with persons entering the medical profession. One important exception is Hepatitis B (for health-care providers), because the disease is quite prevalent still and the risk is so high for clinicians and other health-care providers. The false-negative rate for this test is high as well, unless performed 1-2 months after the 3rd dose, hence the complicated revaccination recommendations.

  2. What four viruses have been eliminated from the U.S. by vaccine?

    Smallpox (1949); Polio (1979); Measles (1994); Rubella (2004)

  3. Are the diluents for MMR, MMRV, Varivax, and Zostavax interchangeable?

    Yes. This diluent is produced by Merck and can be used for any of these four Merck vaccines.

  4. The Pediarix insert says the interval between doses is 6-8 weeks (preferably 8 weeks). I thought I heard you say on the broadcast that the interval between dose 1 and dose 2 could be as short as 4 weeks. Please explain.

    An interval of 6-8 weeks is recommended. It is acceptable to use minimum intervals as long as you do not violate the minimum intervals for any component in a combination vaccine. Pediarix consists of DTaP, IPV, and hepatitis B vaccine. The minimum interval between the first and second doses of each of these components is 4 weeks.

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This page last modified on March 23, 2007



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