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Recommendations To Help Patients Avoid Exposure to or Infection from Opportunistic Pathogens* 

Sexual Exposures

Patients should use a latex condom during every act of sexual intercourse to reduce the risk for acquiring cytomegalovirus, herpes simplex virus, and human papillomavirus, as well as other sexually transmitted pathogens (AII). Condom use also will, theoretically, reduce the risk for acquiring human herpesvirus 8, as well as superinfection with a strain of human immunodeficiency virus (HIV) that has become resistant to antiretroviral drugs (BIII) and will prevent transmission of HIV and other sexually transmitted pathogens to others (AII). Data regarding the use and efficacy of female condoms are incomplete, but these devices should be considered a risk-reduction strategy (BIII).

Patients should avoid sexual practices that might result in oral exposure to feces (e.g., oral-anal contact) to reduce the risk for intestinal infections (e.g., cryptosporidiosis, shigellosis, campylobacteriosis, amebiasis, giardiasis, and hepatitis A) (BIII). Latex condom use alone might not reduce the risk for acquiring these fecal-orally transmitted pathogens, chiefly those that have low infectious doses. Persons wishing to reduce their risk for exposure might consider using dental dams or similar barrier methods for oral-anal and oral-genital contact, changing condoms after anal intercourse, and wearing latex gloves during digital-anal contact. Frequent washing of hands and genitals with warm soapy water during and after activities that might bring these body parts in contact with feces might further reduce risk for illness (CIII).

Hepatitis B vaccination is recommended for all susceptible (antihepatitis B core antigen-negative) HIV-infected patients (BII). Hepatitis A vaccination is recommended for all susceptible men who have sex with men, as well as others with indications for hepatitis A virus vaccine (BIII).

Injection-Drug--Use Exposures

Injection-drug use is a complex behavior that puts HIV-infected persons at risk for hepatitis B virus and hepatitis C virus infection, additional, possibly drug-resistant strains of HIV, and other bloodborne pathogens. Providers should assess the person's readiness to change this practice and encourage efforts to provide education and support directed at recovery. Patients should be counseled to stop using injection drugs (AIII) and to enter and complete substance-abuse treatment, including relapse prevention programs (AIII).

For patients who continue to inject drugs, health-care providers should advise them to (BIII)

  • never reuse or share syringes, needles, water, or drug preparation equipment; if, nonetheless, injection equipment that has been used by other persons is shared, they should first clean the equipment with bleach and water (A-1);
  • use only sterile syringes obtained from a reliable source (e.g., pharmacies or syringe-exchange programs);
  • use sterile (e.g., boiled) water to prepare drugs, and if this is not feasible, to use clean water from a reliable source (e.g., fresh tap water); to use a new or disinfected container (i.e., cooker) and a new filter (i.e., cotton) to prepare drugs;
  • clean the injection site with a new alcohol swab before injection;
  • safely dispose of syringes after one use.

All susceptible injection-drug users should be vaccinated against hepatitis B (BII) and hepatitis A (BIII).

Environmental and Occupational Exposures

Certain activities or types of employment might increase the risk for exposure to tuberculosis (BIII). These include volunteer work or employment in health-care facilities, correctional institutions, and shelters for the homeless, as well as other settings identified as high risk by local health authorities. Decisions regarding whether to continue with such activities should be made in conjunction with the health-care provider and should be based on such factors as the patient's specific duties in the workplace, the prevalence of tuberculosis in the community, and the degree to which precautions designed to prevent the transmission of tuberculosis are taken in the workplace (BIII). These decisions will affect the frequency with which the patient should be screened for tuberculosis.

Child-care providers and parents of children in child care are at increased risk for acquiring cytomegalovirus infection, cryptosporidiosis, and other infections (e.g., hepatitis A and giardiasis) from children. The risk for acquiring infection can be diminished by optimal hygienic practices (e.g., hand-washing) after fecal contact (e.g., during diaper changing) and after contact with urine or saliva (AII). All children in child care facilities also are at increased risk for acquiring these same infections; parents and other caretakers of HIV-infected children should be advised of this risk (BIII).

Occupations involving contact with animals (e.g., veterinary work and employment in pet stores, farms, or slaughterhouses) might pose a risk for cryptosporidiosis, toxoplasmosis, salmonellosis, campylobacteriosis, or Bartonella infection. However, available data are insufficient to justify a recommendation against HIV-infected persons working in such settings.

Contact with young farm animals, specifically animals with diarrhea, should be avoided to reduce the risk for cryptosporidiosis (BII). Hand-washing after gardening or other contact with soil might reduce the risk for cryptosporidiosis and toxoplasmosis (BIII). In areas endemic for histoplasmosis, patients should avoid activities known to be associated with increased risk (e.g., creating dust when working with surface soil; cleaning chicken coops that are heavily contaminated with compost droppings; disturbing soil beneath bird-roosting sites; cleaning, remodeling or demolishing old buildings; and cave exploring) (CIII). In areas endemic for coccidioidomycosis, when possible, patients should avoid activities associated with increased risk, including those involving extensive exposure to disturbed native soil (e.g., at building excavation sites or during dust storms) (CIII).

Pet-Related Exposures

Health-care providers should advise HIV-infected persons of the potential risk posed by pet ownership. However, they should be sensitive to the possible psychological benefits of pet ownership and should not routinely advise HIV-infected persons to part with their pets (DIII). Specifically, providers should advise HIV-infected patients of the following precautions (A-2):


Veterinary care should be sought when a pet develops diarrheal illness. If possible, HIV-infected persons should avoid contact with animals that have diarrhea (BIII). A fecal sample should be obtained from animals with diarrhea and examined for Cryptosporidium, Salmonella, and Campylobacter.

When obtaining a new pet, HIV-infected patients should avoid animals aged <6 months (or <1 year for cats; see the following section) and specifically those with diarrhea (BIII). Because the hygienic and sanitary conditions in pet-breeding facilities, pet stores, and animal shelters are highly variable, the patient should be cautious when obtaining a pet from these sources. Stray animals should be avoided. Animals aged <6 months, and specifically those with diarrhea, should be examined by a veterinarian for Cryptosporidium, Salmonella, and Campylobacter (BIII).

Patients should wash their hands after handling pets, including before eating, and avoid contact with pets' feces to reduce the risk for cryptosporidiosis, salmonellosis, and campylobacteriosis (BIII). Hand-washing for HIV-infected children should be supervised.


Patients should be aware that cat ownership increases their risk for toxoplasmosis and Bartonella infection, as well as enteric infections (CIII). Those who elect to obtain a cat should adopt or purchase an animal that is aged >1 year and in good health to reduce the risk for cryptosporidiosis, Bartonella infection, salmonellosis, and campylobacteriosis (BII).

Litter boxes should be cleaned daily, preferably by an HIV-negative, nonpregnant person; if the HIV-infected patient performs this task, his or her hands should be washed thoroughly afterward to reduce the risk for toxoplasmosis (BIII). To further reduce the risk for toxoplasmosis, HIV-infected patients should keep cats indoors, not allow them to hunt, and not feed them raw or undercooked meat (BIII). Although declawing is not usually advised, patients should avoid activities that might result in cat scratches or bites to reduce the risk for Bartonella infection (BII). Patients should also wash sites of cat scratches or bites promptly (CIII) and should not allow cats to lick the patients' open cuts or wounds (BIII).

Care of cats should include flea control to reduce the risk for Bartonella infection (CIII). Testing cats for toxoplasmosis (EII) or Bartonella infection (DII) is not recommended.


Screening healthy birds for Cryptococcus neoformans, Mycobacterium avium, or Histoplasma capsulatum is not recommended (DIII).


Contact with reptiles (e.g., snakes, lizards, iguanas, and turtles) as well as chicks and ducklings should be avoided to reduce the risk for salmonellosis (BIII). Gloves should be used during aquarium cleaning to reduce the risk for infection with Mycobacterium marinum (BIII). Contact with exotic pets (e.g., nonhuman primates) should be avoided (CIII).

Food and Water-Related Exposures

HIV-infected persons should avoid eating certain foods, including foods that might contain raw eggs (e.g., certain preparations of hollandaise sauce, Caesar and other salad dressings, certain mayonnaises, uncooked cookie and cake batter, and egg nog); raw or undercooked poultry, meat, seafood (raw shellfish in particular ); and unpasteurized dairy products; unpasteurized fruit juice; and raw seed sprouts (e.g., alfalfa sprouts or mung bean sprouts). Poultry and meat are safest when adequate cooking is confirmed with a thermometer (internal temperature of 180ºF for poultry and 165ºF for red meats). If a thermometer is not used, the risk for illness is decreased by consuming poultry and meat that have no trace of pink. However, color change of meat (e.g., absence of pink) does not always correlate with internal temperature. Produce should be washed thoroughly before being eaten (BIII).

Cross-contamination of foods should be avoided. Uncooked meats should not be allowed to come in contact with other foods; hands, cutting boards, counters, and knives and other utensils should be washed thoroughly after contact with uncooked foods (BIII).

Although incidence of listeriosis is low, it is a serious disease that occurs unusually frequently among HIV-infected persons who are severely immunosuppressed. An immunosuppressed, HIV-infected person who wishes to reduce the risk for acquiring listeriosis as much as possible can choose to do the following:

  1. avoid soft cheeses (e.g., feta, Brie, Camembert, blue-veined, and Mexican queso fresco cheese). Hard cheeses, processed cheeses, cream cheese, including slices and spreads, cottage cheese, or yogurt need not be avoided;
  2. cook leftover foods or ready-to-eat foods (e.g., hot dogs) until steaming hot before eating;
  3. avoid foods from delicatessen counters (e.g., prepared salads, meats, cheeses) or heat/reheat these foods until steaming before eating;
  4. avoid refrigerated pâtés and other meat spreads, or heat/reheat these foods until steaming if eaten; canned or shelf-stable pâté and meat spreads need not be avoided;
  5. avoid raw or unpasteurized milk, including goat's milk, or milk products, or foods that contain unpasteurized milk or milk products (CIII).

Patients should not drink water directly from lakes or rivers because of the risk for cryptosporidiosis and giardiasis (AIII). Waterborne infection might also result from swallowing water during recreational activities. Patients should avoid swimming in water that is probably contaminated with human or animal waste and should avoid swallowing water during swimming (BII).

During outbreaks or in other situations in which a community boil-water advisory is issued, boiling water for >1 minutes will eliminate the risk for acquiring cryptosporidiosis (AI). Using submicron, personal-use water filters (home/office types) or drinking bottled water might also reduce the risk (see text) (CIII). Available data are inadequate to support a recommendation that all HIV-infected persons boil or otherwise avoid drinking tap water in nonoutbreak settings. However, persons who wish to take independent action to reduce their risk for waterborne cryptosporidiosis might choose to take precautions similar to those recommended during outbreaks. Such decisions are best made in conjunction with a health-care provider. Persons who opt for a personal-use filter or bottled water should be aware of the complexities involved in selecting the appropriate products, the lack of enforceable standards for destruction or removal of oocysts, product cost, and the difficulty of using these products consistently. Patients taking precautions to avoid acquiring cryptosporidiosis from drinking water should be advised that ice made from contaminated tap water also can be a source of infection (BII). Such persons should be aware that fountain beverages served in restaurants, bars, theaters, and other public places might also pose a risk, because these beverages, as well as the ice they might contain, are made from tap water. Nationally distributed brands of bottled or canned carbonated soft drinks are safe to drink. Commercially packaged noncarbonated soft drinks and fruit juices that do not require refrigeration until after they are opened (i.e., those that can be stored unrefrigerated on grocery shelves) also are safe. Nationally distributed brands of frozen fruit juice concentrate are safe if they are reconstituted by the user with water from a safe source. Fruit juices that must be kept refrigerated from the time they are processed to the time of consumption might be either fresh (i.e., unpasteurized) or heat-treated (i.e., pasteurized); only juices labeled as pasteurized should be considered free of risk from Cryptosporidium. Other pasteurized beverages and beers are also considered safe to drink (BII). No data are available concerning survival of Cryptosporidium oocysts in wine.

Travel-Related Exposures

Travel, specifically to developing countries, might result in substantial risks for the exposure of HIV-infected persons to opportunistic pathogens, including for patients who are severely immunosuppressed. Consultation with health-care providers or specialists in travel medicine should help patients plan itineraries (BIII).

During travel to developing countries, HIV-infected persons are at a higher risk for foodborne and waterborne infections than they are in the United States. Foods and beverages, specifically raw fruits and vegetables, raw or undercooked seafood or meat, tap water, ice made with tap water, unpasteurized milk and dairy products, and items purchased from street vendors, might be contaminated (AII). Items that are usually safe include steaming hot foods, fruits that are peeled by the traveler, bottled (including carbonated) beverages, hot coffee or tea, beer, wine, and water brought to a rolling boil for >1 minutes (AII). Treating water with iodine or chlorine might not be as effective as boiling but can be used, perhaps in conjunction with filtration, when boiling is not practical (BIII).

Waterborne infections might result from swallowing water during recreational activities. To reduce the risk for cryptosporidiosis and giardiasis, patients should avoid swallowing water during swimming and should not swim in water that might be contaminated (e.g., with sewage or animal waste) (BII).

Antimicrobial prophylaxis for traveler's diarrhea is not recommended routinely for HIV-infected persons traveling to developing countries (DIII). Such preventive therapy can have adverse effects and can promote the emergence of drug-resistant organisms. Nonetheless, studies (none involving an HIV-infected population) have reported that prophylaxis can reduce the risk for diarrhea among travelers (A-3). Under selected circumstances (e.g., those in which the risk for infection is high and the period of travel brief), the health-care provider and patient might weigh the potential risks and benefits and decide that antibiotic prophylaxis is warranted (CIII). For those persons to whom prophylaxis is offered, fluoroquinolones (e.g., ciprofloxacin [500 mg daily]) can be considered (CIII), although fluoroquinolones should not be administered to children or pregnant women. Trimethoprim-sulfamethoxazole (TMP-SMZ) (one double-strength tablet daily) also has been demonstrated to be effective, but resistance to this drug has become common in tropical areas. Persons already taking TMP-SMZ as prophylaxis against Pneumocystis carinii pneumonia (PCP) might gain protection against traveler's diarrhea. For HIV-infected persons who are not already taking TMP-SMZ, health-care providers should be cautious in prescribing this agent for prophylaxis of diarrhea because of increased rates of adverse reactions and possible need for the agent for other purposes (e.g., PCP prophylaxis) in the future.

All HIV-infected travelers to developing countries should carry a sufficient supply of an antimicrobial agent to be taken empirically if diarrhea occurs (BIII). One appropriate regimen is 500 mg of ciprofloxacin twice daily for 3--7 days. Alternative antibiotics (e.g., TMP-SMZ) should be considered as empirical therapy for use by children and pregnant women (CIII). Travelers should consult a physician if their diarrhea is severe and does not respond to empirical therapy, if their stools contain blood, if fever is accompanied by shaking chills, or if dehydration occurs. Antiperistaltic agents (e.g., diphenoxylate and loperamide) are used for treating diarrhea; however, they should not be used by patients with high fever or with blood in the stool, and their use should be discontinued if symptoms persist >48 hours (AII). Antiperistaltic agents are not recommended for children (DIII).

Travelers should be advised concerning other preventive measures appropriate for anticipated exposures (e.g., chemoprophylaxis for malaria, protection against arthropod vectors, treatment with immune globulin, and vaccination) (AII). They should avoid direct contact of the skin with soil or sand (e.g., by wearing shoes and protective clothing and by using towels on beaches) in areas where fecal contamination of soil is likely (BIII).

Typically, live-virus vaccines should be avoided (EII). One exception is measles vaccine, which is recommended for nonimmune persons. However, measles vaccine is not recommended for persons who are severely immunosuppressed (DIII); immune globulin should be considered for measles-susceptible, severely immunosuppressed persons who are anticipating travel to measles-endemic countries (BIII). Another exception is varicella vaccine, which can be administered to asymptomatic nonimmunosuppressed children (BII). Inactivated (killed) poliovirus vaccine should be used instead of oral (live) poliovirus vaccine, which is contraindicated for HIV-infected persons. Persons at risk for exposure to typhoid fever should be administered an inactivated parenteral typhoid vaccine instead of the live-attenuated oral preparation. Yellow fever vaccine is a live-virus vaccine with uncertain safety and efficacy among HIV-infected persons. Travelers with asymptomatic HIV infection who cannot avoid potential exposure to yellow fever should be offered the choice of vaccination. If travel to a zone with yellow fever is necessary and vaccination is not administered, patients should be advised of the risk, instructed in methods for avoiding the bites of vector mosquitoes, and provided with a vaccination waiver letter.

Usually, killed and recombinant vaccines (e.g., diphtheria-tetanus, rabies, hepatitis A, hepatitis B, Japanese encephalitis vaccines) should be used for HIV-infected persons just as they would be used for non-HIV--infected persons anticipating travel (BIII). Preparation for travel should include a review and updating of routine vaccinations, including diphtheria-tetanus for adults and all routine immunizations for children. The available cholera vaccine is not recommended for persons after a routine tourist itinerary, even if travel includes countries reporting cases of cholera (DII).

Travelers should be informed regarding other area-specific risks and instructed in ways to reduce those risks (BIII). Geographically focal infections that pose an increased risk to HIV-infected persons include visceral leishmaniasis (a protozoan infection transmitted by the sandfly) and different fungal infections (e.g., Penicillium marneffei infection, coccidioidomycosis, and histoplasmosis). Certain tropical and developing areas have high rates of tuberculosis.


A-1. US Public Health Service. HIV prevention bulletin: medical advice for persons who inject illicit drugs -- May 8, 1997. Rockville, MD: Us Public Health Service, CDC, 1997.

A-2. CDC. 1999 USPHS/IDSA guidelines for the prevention of opportunistic infections in persons infected with human immunodeficiency virus: U.S. Public Health Service (USPHS) and Infectious Diseases Society of America (IDSA). MMWR 1999;48(No. RR-10):1--66.

A-3. CDC. Health information for international travel, 1999--2000. Atlanta, GA: US Department of Health and Human Services, 1999:202.

*Letters and Roman numerals in parentheses indicate the strength of the recommendation and the quality of evidence supporting it (see Box in text).

List of Abbreviations Used in This Report

AIDS  acquired immunodeficiency syndrome
ASCUS  atypical squamous cells of undetermined significance
ATIS  HIV/AIDS Treatment Information Service
BCG  bacille Calmette-Guérin




cerebrospinal fluid
CYP450  cytochrome P450
DNA  deoxyribonucleic acid
EIA  enzyme immunoassays
FDA  Food and Drug Administration


granulocyte-colony-stimulating factor
HAART  highly active antiretroviral therapy
HCV  hepatitis C virus
HHV-8  human herpesvirus 8
Hib  Haemophilus influenzae type B


human immunodeficiency virus
HPV  human papillomavirus


high-grade squamous intraepithelial lesions
HSV  herpes simplex virus


Infectious Diseases Society of America
IgG  immunoglobulin G
IgM  immunoglobulin M


intravenous immune globulin
KS  Kaposi sarcoma
LSIL  low-grade squamous intraepithelial lesion


Mycobacterium avium complex

NNRTI  nonnucleoside reverse transcriptase inhibitor


opportunistic infection
Pap  Papanicolaou


Pneumocystis carinii pneumonia


pneumococcal conjugate vaccine


polysaccharide pneumococcal vaccine


protease inhibitor


purified protein derivative
RIBA  recombinant immunoblot assay
RNA  ribonucleic acid


respiratory syncytial virus
RT-PCR  reverse transcriptase-polymerase chain reaction
TB  tuberculosis
TST  tuberculin skin test


toxoplasmic encephalitis



USPHS  U.S. Public Health Service


varicella-zoster immune globulin
VZV  varicella-zoster virus

U.S. Public Health Service and Infectious Diseases Society of America Prevention of Opportunistic Infections Working Group

Co-Chairs: Henry Masur, M.D., National Institutes of Health, Bethesda, Maryland; Jonathan E. Kaplan, M.D., CDC, Atlanta, Georgia; and King K. Holmes, M.D., Ph.D., University of Washington, Seattle, Washington.

Members: Beverly Alston, M.D., National Institutes of Health, Bethesda, Maryland; Miriam J. Alter, Ph.D., CDC, Atlanta, Georgia; Neil Ampel, M.D., University of Arizona, Tucson, Arizona; Jean R. Anderson, M.D., Johns Hopkins University, Baltimore, Maryland; A. Cornelius Baker, Whitman Walker Clinic, Washington, D.C.; David Barr, Forum for Collaborative HIV Research, Washington, D.C.; John G. Bartlett, M.D., Johns Hopkins University, Baltimore, Maryland; John E. Bennett, M.D., National Institutes of Health, Bethesda, Maryland; Constance A. Benson, M.D., University of Colorado, Denver, Colorado; William A. Bower, M.D., CDC, Atlanta, Georgia; Samuel A. Bozzette, M.D., University of California, San Diego, California; John T. Brooks, M.D., CDC, Atlanta, Georgia; Victoria A. Cargill, M.D., National Institutes of Health, Bethesda, Maryland; Kenneth G. Castro, M.D., CDC, Atlanta, Georgia; Richard E. Chaisson, M.D., Johns Hopkins University, Baltimore, Maryland; David Cooper, M.D., D.Sc., University of New South Wales, Sydney, Australia; Clyde S. Crumpacker, M.D., Beth Israel Deaconess Medical Center, Boston, Massachusetts; Judith S. Currier, M.D., University of California -- Los Angeles Medical Center, Los Angeles, California; Kevin M. DeCock, M.D., CDC, Atlanta, Georgia; Lawrence Deyton, M.D., U.S. Department of Veterans Affairs, Washington, D.C.; Scott F. Dowell, M.D., CDC, Atlanta, Georgia; W. Lawrence Drew, M.D., Ph.D.; University of California -- Mt. Zion Medical Center, San Francisco, California; William R. Duncan, Ph.D., National Institutes of Health, Bethesda, Maryland; Mark S. Dworkin, M.D., CDC, Atlanta, Georgia; Clare Dykewicz, M.D., CDC, Atlanta, Georgia; Robert W. Eisinger, Ph.D., National Institutes of Health, Bethesda, Maryland; Tedd Ellerbrock, M.D., CDC, Atlanta, Georgia; Wafaa El-Sadr, M.D., Harlem Hospital, New York, New York; Judith Feinberg, M.D., Holmes Hospital, Cincinnati, Ohio; Kenneth A. Freedberg, M.D., Massachusetts General Hospital, Boston, Massachusetts; Keiji Fukuda, M.D., CDC, Atlanta, Georgia; Hansjakob Furrer, M.D., University Hospital, Berne, Switzerland; Jose M. Gatell, M.D., Ph.D., Hospital Clinic, Barcelona, Spain; John W. Gnann, Jr., M.D., University of Alabama, Birmingham, Alabama; Mark J. Goldberger, M.D., Food and Drug Administration, Rockville, Maryland; Sue Goldie, M.D., Harvard School of Public Health, Boston, Massachusetts; Eric P. Goosby, M.D., U.S. Department of Health and Human Services, Washington, D.C.; Fred Gordin, M.D., Veterans Administration Medical Center, Washington, D.C.; Peter A. Gross, M.D., Hackensack University -- Hackensack Medical Center, New Jersey; Rana Hajjeh, M.D., CDC, Atlanta, Georgia; Richard Hafner, M.D., National Institutes of Health, Bethesda, Maryland; Diane Havlir, M.D., University of California, San Diego, California; Scott Holmberg, M.D., CDC, Atlanta, Georgia; David R. Holtgrave, Ph.D., CDC, Atlanta, Georgia; Thomas M. Hooton, M.D., Harborview Medical Center, Seattle, Washington; Douglas A. Jabs, M.D., Johns Hopkins University, Baltimore, Maryland; Mark A. Jacobson, M.D., University of California, San Francisco, California; Harold Jaffe, M.D., CDC, Atlanta, Georgia; Edward Janoff, M.D., Veterans Administration Medical Center, Minneapolis, Minnesota; Jeffrey Jones, M.D., CDC, Atlanta, Georgia; Dennis D. Juranek, D.V.M., CDC, Atlanta, Georgia; Mari Kitahata, M.D., Ph.D., University of Washington, Seattle, Washington; Joseph A. Kovacs, M.D., National Institutes of Health, Bethesda, Maryland; Catherine Leport, M.D., Hospital Bichat-Claude Bernard, Paris, France; Myron J. Levin, M.D., University of Colorado Health Science Center, Denver, Colorado; Juan C. Lopez, M.D., Hospital Universatario Gregorio Maranon, Madrid, Spain; Jens Lundgren, M.D., Hvidore Hospital, Copenhagen, Denmark; Michael Marco, Treatment Action Group, New York, New York; Eric Mast, M.D., CDC, Atlanta, Georgia; Douglas Mayers, M.D., Henry Ford Hospital, Detroit, Michigan; Lynne M. Mofenson, M.D., National Institutes of Health, Bethesda, Maryland; Julio S.G. Montaner, M.D., St. Paul's Hospital, Vancouver, Canada; Richard Moore, M.D., Johns Hopkins Hospital, Baltimore, Maryland; Thomas Navin, M.D., CDC, Atlanta, Georgia; James Neaton, Ph.D., University of Minnesota, Minneapolis, Minnesota; Charles Nelson, National Association of People with AIDS, Washington, D.C.; Joseph F. O'Neill, M.D. Health Resources and Services Administration, Rockville, Maryland; Joel Palefsky, M.D., University of California, San Francisco, California; Alice Pau, Pharm.D., National Institutes of Health, Bethesda, Maryland; Phil Pellett, Ph.D., CDC, Atlanta, Georgia; John P. Phair, M.D., Northwestern University, Chicago, Illinois; Steve Piscitelli, Pharm.D., National Institutes of Health, Bethesda, Maryland; Michael A. Polis, M.D., National Institutes of Health, Bethesda, Maryland; Thomas C. Quinn, M.D., Johns Hopkins Hospital, Baltimore, Maryland; William C. Reeves, M.D., CDC, Atlanta, Georgia; Peter Reiss, M.D., Ph.D., University of Amsterdam, the Netherlands; David Rimland, M.D., Veterans Administration Medical Center, Atlanta, Georgia; Anne Schuchat, M.D., CDC, Atlanta, Georgia; Cynthia L. Sears, M.D., Johns Hopkins Hospital, Baltimore, Maryland; Leonard Seeff, M.D., National Institutes of Health, Bethesda, Maryland; Kent A. Sepkowitz, M.D., Memorial Sloan-Kettering Cancer Center, New York, New York; Kenneth E. Sherman, M.D., Ph.D., University of Cincinnati, Cincinnati, Ohio; Thomas G. Slama, M.D., National Foundation for Infectious Diseases, Indianapolis, Indiana; Elaine M. Sloand, M.D., National Institutes of Health, Bethesda, Maryland; Stephen A. Spector, M.D., University of California, La Jolla, California; John A. Stewart, M.D., CDC, Atlanta, Georgia; David L. Thomas, M.D., MPH, Johns Hopkins Hospital, Baltimore, Maryland; Timothy M. Uyeki, M.D., CDC, Atlanta, Georgia; Russell B. Van Dyke, M.D., Tulane School of Medicine, New Orleans, Louisiana; M. Elsa Villarino, M.D., CDC, Atlanta, Georgia; Anna Wald, M.D., University of Seattle, Seattle, Washington; D. Heather Watts, M.D., National Institutes of Health, Bethesda, Maryland; L. Joseph Wheat, M.D., Indiana University School of Medicine, Indianapolis, Indiana; Paige Williams, Ph.D., Harvard School of Public Health, Boston, Massachusetts; and Thomas C. Wright, Jr., M.D., Columbia University College of Physicians and Surgeons, New York, New York.

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