Vaccine Eligibility & Recommendations
Dengue is the disease caused by four distinct, but closely related dengue viruses, DENV-1–4. People can be infected with dengue virus up to four times in their life. The second dengue virus infection is most likely to cause hospitalization or severe disease.
Children and adolescents 9–16 years old with laboratory confirmation of previous dengue virus infection and living in dengue-endemic areas are eligible for the Dengvaxia dengue vaccine. Dengvaxia requires three doses and can prevent dengue illness, hospitalization, and severe dengue from all four dengue viruses.
DO NOT vaccinate a person without laboratory evidence of previous dengue virus infection
In people who have not had dengue before, the vaccine could increase the risk of hospitalization or severe dengue if a person gets dengue after vaccination.
- If you vaccinate a person who has never been infected with dengue virus, they skip the first, natural infection.
- If the person is then infected after vaccination, they will experience an infection that is similar to the second dengue virus infection, which poses the highest risk for severe disease.
- The mechanism causing greater severity of the second dengue virus infection includes antibody-dependent enhancement, which can lead to plasma leakage and severe disease.
Vaccinate a person with laboratory evidence of previous dengue virus infection
- If you vaccinate a child who has been previously infected with dengue virus, the child skips the second dengue virus infection.
- If infected after vaccination, the child will experience an infection that is similar to the third or fourth dengue virus infection, which are the lowest risk for severe disease.
Pre-Vaccination Screening for Previous Dengue Virus Infection
Laboratory confirmation of previous dengue virus infection is required and can be obtained by:
- Evidence of a prior acute dengue virus infection with
- Positive dengue RT-PCR test result, or
- Positive dengue NS1 antigen test
- Or, positive test results on pre-vaccination screening tests. See Laboratory Testing Requirements for Vaccination with Dengvaxia Dengue Vaccine for more information on pre-vaccination screening.