Discussion
yellow fever
ADVERSE EVENTS, DISEASE, EVENTS, YELLOW FEVER, SEQUELAE
Mass pre-emptive and reactive vaccination campaigns in yellow fever endemic regions have substantial benefits in tackling epidemics.To our knowledge, this substudy is the first randomised controlled non-inferiority trial assessing fractional doses and standard doses of a yellow fever vaccine in a population of HIV-infected adults in Africa.There was good compliance with the protocol among trial participants, with an attrition rate of 9% at long-term follow-up. The baseline positivity for yellow fever as measured by PRNTA single dose of the fractional dose (one-fifth of the standard dose) induced robust immunity with high neutralising antibody titres similar to the standard dose. The primary outcome, non-inferiority of seroconversion at 28 days after vaccination as measured by PRNTThere were local and systemic adverse events reported in both vaccine dose groups, with participants in the fractional doses group reporting fewer events. There were no safety concerns, because all adverse events were either mild or moderate in severity and resolved without sequelae, and none of the serious adverse events were related to vaccine administration or participation in the study. The safety profile was consistent with previous studies in HIV-infected individuals.Consistent with the results of the preceding study,Individuals with CD4This study has several limitations. First, in epidemic settings, HIV-infected people might have varying disease severity and might be severely immunocompromised. However, we did not assess individuals with CD4In conclusion, fractional doses of the 17D-213 yellow fever vaccine are safe, effective, and immunologically non-inferior to standard doses in HIV-infected individuals on antiretroviral therapy with CD4