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Clinical Immunization Safety Assessment (CISA) Project Current Studies

CISA studies use the most current methods and technology to investigate questions of key importance to vaccine safety.

Studies initiated under the CISA Project from 2012 to the present.


  • Pilot study to assess the effect of prophylactic antipyretics on immune responses and rates of fever after the 2013-2014 Inactivated Influenza Vaccine (IIV) in young children
    Using prophylactic antipyretics, such as acetaminophen, immediately after the vaccination and during the next 24 hours reduces the rate of fever after vaccination.  However prophylactic antipyretics may also blunt immune responses to the vaccine. CISA is conducting a double-blind, pilot study to assess the effect of prophylactic antipyretics on the immune responses and rates of fever after inactivated influenza vaccine (IIV) in healthy children 12 through 35 months of age. Children are randomized to receive prophylactic acetaminophen or oral placebo immediately after receipt of IIV.  Information from this pilot study will be used design larger studies to better understand potential risks and benefits of using prophylactic antipyretics to prevent fever or febrile seizure after IIV.
    More information about this study can be found at (NCT01946594)
    Lead CISA Site: Duke University
    Collaborator: CDC
  • Assessing the Feasibility of Monitoring Influenza Vaccine Safety in Pregnant Women Using Text Messaging
    Text messaging may be a convenient and cost-efficient way to monitor vaccine safety in pregnant women, but it has not been studied. CISA is conducting a study to assess the feasibility of using text messaging to monitor the safety of inactivated influenza vaccine (IIV) in pregnant women. Pregnant women <20 weeks gestation receiving IIV as part of usual care are included.  These women receive periodic text messages after IIV throughout their pregnancy to 1) monitor rates of fever shortly after IIV and 2) assess pregnancy outcomes. Results of this study may help enhance future vaccine safety monitoring efforts in pregnant women and preparedness for an influenza pandemic.
    More information about this study can be found at (NCT01974050)
    Lead CISA Site: Columbia University.
    Collaborator: CDC
  • Immune response to influenza vaccination and effect on reproductive hormones
    Influenza vaccine is routinely recommended for people 6 months of age and older, including women of reproductive age. Giving inactivated influenza vaccine (IIV) induces an early immune or germ-fighting response and changes the body’s level of cytokines.  Cytokines are substances that are secreted by immune cells and act on other cells to coordinate appropriate immune responses.  It is not known whether this cytokine response might affect female reproductive hormone levels.  CISA is conducting a pilot study to assess whether women’s reproductive hormone levels change during the menstrual cycle after receiving IIV. Healthy women 18-39 years of age are participating during 2 menstrual cycles. In one cycle the women receive IIV during the week before ovulation, and in the other cycle (control cycle) they do not receive any vaccines. The level of reproductive hormones and cytokines are being measured during these menstrual cycles at several time points.  This study is assessing the feasibility of conducting further research in this area in order to better understand the effects of vaccination on women’s reproductive hormones.
    More information about this study can be found at (NCT01978262)
    Lead CISA Site: Johns Hopkins University.
    Collaborator: CDC
  • Clinical Study of Tetanus Toxoid, Reduced Diphtheria Toxoid, and Acellular Pertussis Vaccine (Tdap) Safety in Pregnant Women
    Tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis vaccine (Tdap) is routinely recommended during each pregnancy(MMWR, February 22, 2013 / 62(07); 131-135).  When a woman receives Tdap during pregnancy she makes antibodies against pertussis (whooping cough) that are transferred to the baby across the placenta.  These antibodies provide some protection to infants from pertussis until they are old enough to be vaccinated themselves.  CISA  is conducting a multisite study to evaluate health outcomes in women who receive Tdap during pregnancy.  Pregnant women ≥20 weeks gestational age and non-pregnant women receiving Tdap vaccine as part of routine care are participating.    The study is comparing rates of injection site and systemic reactions, such as fever, after Tdap in pregnant women versus non-pregnant women.  It is also assessing rates of preterm birth and small for gestational age (SGA) in women who receive Tdap during pregnancy, compared with background rates of these conditions.  Pregnant women enrolled in the study are participating through delivery.   Their infants are also being evaluated for health outcomes and growth parameters through age 6 months.  Non-pregnant women are participating  for one month after vaccination. This study will provide additional information about the safety of using Tdap in pregnant women, including repeated Tdap doses.
    More information about this study can be found at (NCT 02209623)
    Lead CISA Site: Vanderbilt University
    Contributing CISA Site: Duke University
    Collaborator: CDC, National Vaccine Program Office
  • Enhancing an Online Tool for Assessing the Causality of Adverse Events Following Immunization
    The US National Vaccine Plan ( has an objective to improve causality assessments of vaccines and associated adverse events following immunization (AEFI). CISA has created an algorithm to guide healthcare providers through the steps necessary to evaluate whether a vaccine might have been associated in a causal way with the development of an AEFI in an individual patient. There is also an online test tool that can be accessed at The purpose of this project is to enhance the online causality test tool for AEFI and determine how useful it might be to clinicians and public health professionals, outside the CISA Project.
    Lead CISA Site: Johns Hopkins University.
    Collaborator: CDC


  • Assessing Fever Rates in Children ages 24 to 59 months after Live Attenuated Influenza Vaccine(LAIV) or Inactivated Influenza Vaccines (IIV) Using Text Messaging for U.S. influenza vaccines in 2012–13 & 2013-2014
    Some children have fevers after receiving vaccines, including influenza vaccines.  In recent years there have been 4 main kinds of influenza vaccines for children:  trivalent inactivated influenza vaccine (IIV3) (3 strain, flu shot), trivalent live attenuated influenza vaccine (LAIV3) (3 strain, nasal spray), IIV4 (4 strain, flu shot) and LAIV4 (4 strain, nasal spray).  CISA is conducting a study that is assessing the rates of fever in healthy children 24-59 months of age after they receive pediatric influenza vaccines. The child’s temperature is taken on vaccination day (day 0) and for the next 10 days. These temperature readings are sent to study staff using text messaging each day. The main objective is to compare rates of fever after LAIV vs IIV in the 0-2 days after vaccination, when rates of fever are expected to be highest. Information from this study will help healthcare providers and parents better understand the risk for fever in young children after different kinds of influenza vaccines. 
    More information about this study can be found at (NCT01764269)
    Lead CISA Site: Columbia University.
    Collaborator: CDC
  • Pilot Study to Assess Flares of Illness Following Receipt of Inactivated Influenza Vaccine in Youth with Systemic Lupus Erythematosus (SLE)
    Vaccines stimulate the immune system to develop protection against diseases. The effect of vaccination on disease progression among people with autoimmune diseases who are immunosuppressed is not well studied. CISA is conducting a pilot study of inactivated influenza vaccine (IIV) safety in children/adolescents with systemic lupus erythematosus (SLE) who are immunosuppressed, in order to inform methods for a larger study assessing association of IIV and SLE flares.
    More information about this study can be found at (NCT02006784)
    Lead CISA Site: Vanderbilt University, with subcontract to the Baylor Institute for Immunology Research (BIIR).
    Collaborator: CDC

Projects/Studies initiated under the CISA Network (2001-2012)

The CISA Network has published numerous studies and technical reports on vaccine safety.

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