ABSTRACT
This study reports a type 1 poliovirus strain isolated in Brazil from a case classified as vaccine-associated paralytic poliomyelitis (VAPP). After serotyping of the viral isolate with hyperimmune equine sera, PCR and molecular hybridization techniques characterized the strain as P1/Sabin-derived. The isolate was partially sequenced to identify mutations at nucleotides 480, 525 and 6203, which are important for reversion of the P1/Sabin strain to neurovirulence. In a recent study, a P1/ Sabin-derived strain isolated from the central nervous system of a VAPP case did not mutate at these positions, but maintained 480-G and 525-U (and 6203-C), suggesting that these mutations are not essential for the occurrence of disease (Georgescu et al., (1994), Journal of Virology, 68: 8089-8101). Although the Brazilian strain also maintained 480-G and 525-U (and 6203-C) and was isolated from the stool, the possibility that this isolate invaded the central nervous system after replicating in the gut, causing the paralysis, cannot be ruled out. This is the first report of a type I VAPP case in Brazil, although some cases caused by type 2 and type 3 strains have been described.
Subject(s)
Humans , Child, Preschool , Poliomyelitis/virology , Poliovirus Vaccine, Oral/adverse effects , Brazil , Mutation , Polymerase Chain Reaction , Poliovirus Vaccine, Oral/geneticsABSTRACT
The number of HIV infected heterosexual has been steadily increasing in Brazil. This fact was followed by a decline on the ratio of male/female HIV infection every year. We have examined the seroprevalence of HIV infection among pregnant women attending an antenatal clinic in the Instituto Materno Infantil de Pernambuco (IMIP) at Recife, North-eastern Brazil. This study was performae as an anonymous sentinel surveillance. The collected blood samples were tested for HIV infection by two different types of ELISA, and if positive, further analysis by IIA was submitted. The subjects were arranged in four age groups with the respective proportion: group l (<15 years)-0.9 per cent, group II (15 to 20 years)-31.6 per cent, group III (21 to 34 years)-61.7 per cent and group IV (>35 years)- 5,8 per cent. It was found an HIV-1 seroprevalence of 0.1 per cent (95 per cent confidence interval, -0.l to + 0,3) This percentage represents one single HIV positive woman included in age group III. his low HIV infection seroprevalence is suitable with a low risk population (pregnant women) in a low prevalence area. However, we became concerned with the great propottion of pregnant woman under 21 years (32,5 per cent) and with the implications of how to reinforce effectively HIV preventions of how to reinforce effectively HIV prevention strategies to this population