title: Relationship among epidemiological parameters of six childhood infections in a non-immunized Brazilian community.
abstract: Epidemiological parameters, such as age-dependent force of infection and average age at infection (<IMG SRC='../img/13s1.gif' WIDTH=9 HEIGHT=12>) were estimated for rubella, varicella, rotavirus A, respiratory syncytial virus, hepatitis A and parvovirus B19 infections for a non-immunized Brazilian community, using the same sera samples. The for the aforementioned diseases were 8.45 years (yr) [95% CI: (7.23, 9.48) yr], 3.90 yr [95% CI: (3.51, 4.28) yr], 1.03 yr [95% CI: (0.96, 1.09) yr], 1.58 yr [95% CI: (1.39, 1.79) yr], 7.17 yr [95% CI: (6.48, 7.80) yr] and 7.43 yr [95% CI: (5.68, 9.59) yr], respectively. The differences between average ages could be explained by factors such as differences in the effectiveness of the protection conferred to newborns by maternally derived antibodies, competition between virus species and age-dependent host susceptibility. Our seroprevalence data may illustrate a case of the above-mentioned mechanisms working together within the same population.
authors.affiliation: Departamento de Patologia, Faculdade de Medicina Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, SP, Brasil, 05508-270. amaku@usp.br
authors.forename: Marcos
authors.initials: M
authors.lastname: Amaku
authors.forename: Raymundo Soares
authors.initials: RS
authors.lastname: Azevedo
authors.forename: Ruy Morgado de
authors.initials: RM
authors.lastname: Castro
authors.forename: Eduardo
authors.initials: E
authors.lastname: Massad
authors.forename: Francisco Antonio Bezerra
authors.initials: FA
authors.lastname: Coutinho
mesh_terms: D000293:Adolescent; D000328:Adult; D001938:Brazil / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D009010:Monte Carlo Method; D015995:Prevalence; D016036:Seroepidemiologic Studies; D014777:Virus Diseases / Q000453:epidemiology* / Q000276:immunology; D055815:Young Adult