Modelling the Force of Infection for Hepatitis A in an Urban Population-Based Survey: A Comparison of Transmission Patterns in Brazilian Macro-Regions

摘要: Background: This study aimed to identify the transmission pattern of hepatitis A (HA) infection based on a primary dataset from Brazilian National Hepatitis Survey in pre-vaccination context. The national survey conducted urban areas disclosed two epidemiological scenarios with low and intermediate HA endemicity. Methods: catalytic model was built seroprevalence (2005 2009). data 7,062 individuals aged 5–69 years all macro-regions were included. We up three models: fully homogeneous mixing model, constant contact pattern; highly assortative additional component accounting for contacts infected food/water. Curves prevalence, force (FOI) number new infections 99% confidence intervals (CIs) compared between (North, Northeast, Midwest Federal District) (South Southeast) endemicity areas. contour plot also constructed. Results: anti- HAV IgG 68.8% (95% CI, 64.8%–72.5%) 33.7% 32.4%–35.1%) areas, respectively, according field analysis. models showed that higher identified 10- 19-year-old age cohort (,9,000 per year 100,000 susceptible persons) area, whereas occurred 15- 29-yearold (,6,000 other macro-regions. Conclusion: Our findings support shift Brazil toward levels risk older groups. These estimates stratified by are useful information characterize scenario Brazil.