SEROEPIDEMIOLOGICAL STUDY OF RESPIRATORY SYNCYTIAL VIRUS IN SAO-PAULOSTATE, BRAZIL

Transmission of respiratory syncytial virus is thought to be highly se asonal based on reported clinical cases, although transmission resulti ng in mild disease in all age groups has been little studied. This has been investigated in a seroepidemiological survey using sera from Sao Paulo, Brazil. Seroprevalence was found to increase rapidly with age, reaching over 90% by three years of age. This is typical of viral inf ections, which produce life-long immunity following primary infection. One-hundred percent seropositivity was attained by five years of age and maintained throughout adulthood, whereas mean antibody titers cont inued to increase with age. The mean duration of maternal antibodies w as estimated to be 3.3 months with antibody decay demonstrated in pair ed samples from infants. The results are discussed in relation to poss ible mechanisms generating such a profile. (C) 1998 Wiley-Liss, Inc.