Influenza A and B antibody status in Tanzania.

Sera from 200 babies and young children and from 205 mother-newborn pairs were tested for haemagglutination inhibiting antibody against three A-H1N1, one A-H2N2, four A-H3N2, and two influenza B viruses. The results indicated that a higher concentration of antibody against all influenza A and B viruses tested was found more frequently in maternal sera than in neonatal sera. High prevalences of antibody and high geometric mean titres against the A-H2N2-1957 and A-H3N2-1968 viruses from the eras 1957-1968 and 1968-now, respectively, were found in the age groups above 15 years. The antibodies against former and recent epidemic influenza viruses of the A-H3N2 subtype, found among different adult age groups in Mwanza, Tanzania, showed a pattern similar to that in the population of The Netherlands.