Simultaneous administration of hepatitis B and yellow fever vaccines.

In most developing countries, hepatitis prevention has to be carried out early in life and on a mass scale. In such countries, mobile immunization teams have a limited number of sessions to devote to each rural community ans simultaneous administration of multiple antigens is normal practice. We have, therefore, compared the immune response to yellow fever and hepatitis B vaccines when injected simultaneously or not to Senegalese children. Injections were done at time of booster injections for hepatitis B vaccine. Yellow fever antibodies were detected in a similar proportion in infants immunized with yellow fever vaccine. However, a lower proportion of high yellow fever antibody levels was observed when the two vaccines were injected simultaneously. No reduction in the anti-HBs anamnestic response was observed when yellow fever vaccine was injected at the same time as the booster dose of hepatitis B vaccine. As no untowards reactions were noted, it can be concluded from the results that hepatitis B vaccine and yellow fever vaccine could be injected at the same time.