Dengue Effectiveness Study in the Philippines

CASE-CONTROL STUDIES

• For a suspected case to be enrolled in the study, he/she should:

  • Provide signed informed consent and assent (as applicable)
  • Be within the age group eligible to receive the dengue vaccine at the time of mass vaccination (i.e. no condition that would have made him/her ineligible for dengue vaccination)
  • Be admitted in any of the participating hospitals for suspected dengue
  • Have ≤5 days history of fever.
  • For the case to be included in the analysis, the participant must meet all the inclusion criteria above plus have virologically-confirmed dengue infection by RT-PCR

• For controls to be recruited into the study, he/she should:

  • Provide signed informed consent and assent (as applicable)
  • Be age and sex-matched to the case
  • Be from the same community as the matched case
  • Be eligible to have received dengue vaccine during the community-based dengue immunization campaign in 2017 (i.e. no condition that would have made him/her ineligible for dengue vaccination)
  • Have had no episode of clinically-diagnosed or laboratory-confirmed dengue fever from the start of the community -based dengue immunization campaign to the focal time (the date of onset of dengue fever in the matched case)
  • Should not have been previously recruited as a control.

Exclusion Criteria:

• Any subject whose parent/guardian refuse to provide informed consent and/or assent.

• In addition, the following conditions automatically exclude children from the dengue mass immunization:

  • Children \<9 years or adults older than 45 years of age
  • Anyone who is allergic or has had an allergic reaction to a prior dose or to any component of the dengue vaccine
  • Recipient of blood product in the last 3 months
  • Immunocompromised individuals, due to but not limited to genetic defects, HIV infection, or therapies that affect the immune system such as high-dose corticosteroids or chemotherapy
  • Recipient of any vaccine within the past month
  • History of bleeding disorder
  • Pregnant or breastfeeding women
  • Enrolled in dengue vaccine Phase 3 clinical study