Spatial analysis of pneumococcal meningitis in São Paulo in the pre- and post-immunization era

ABSTRACT OBJECTIVE To analyze the pneumococcal meningitis incidence rates in the State of São Paulo, Brazil, by age group, municipalities and micro-regions, as well as the spatial distribution of pneumococcal meningitis incidence rates among children under 5 years old in the pre- (2005-2009) and post-vaccination (2011-2013) periods and its associations with socioeconomic variables and vaccination coverage. METHODS The data source was the Brazilian Notifiable Diseases Information System. For the pre- and post-vaccination periods, thematic maps were built for pneumococcal meningitis incidence in under-5 children, by São Paulo state micro-regions, vaccination coverage and socioeconomic variables, using QGIS 2.6.1 software. Scan statistics performed by the SatScan 9.2 software were used to analyze spatial and spatiotemporal clusters in São Paulo municipalities and micro-regions. A Bayesian inference for latent Gaussian model with zero-inflated Poisson model through the integrated nested Laplace approximation was used in the spatial analysis to evaluate associations between pneumococcal meningitis incidence rates and socioeconomic variables of interest in São Paulo micro-regions. RESULTS From 2005 to 2013, 3,963 pneumococcal meningitis cases were reported in São Paulo. Under-5 children were the most affected in the whole period. In the post-vaccination period, pneumococcal meningitis incidence rates decreased among this population, particularly among infants (from 4.17/100,000 in 2005 to 2.54/100,000 in 2013). Two clusters were found in pre-vaccination - one of low risk for pneumococcal meningitis, in the northwest of the state (OR = 0.45, p = 0.0003); and another of high risk in the southeast (OR = 1.62, p = 0.0000). In the post-vaccination period, only a high-risk cluster remained, in the southeast (RR = 1.97, p = 0.0570). In Bayesian analysis, wealth was the only variable positively associated to pneumococcal meningitis (RR = 1.026, 95%CI 1.002-1.052). CONCLUSIONS Pneumococcal meningitis is probably underdiagnosed and underreported in São Paulo. Differentiated rates of pneumococcal meningitis diagnosis and reporting in each microregion, according to the São Paulo Index of Social Responsibility, might explain our results.

Risco espacial de óbito de pacientes com aids em Campinas, São Paulo, Brasil / Spatial risk of death in patients with AIDS in Campinas, São Paulo, Brazil

RESUMO: Objetivo: O estudo teve como objetivo analisar o risco espacial de mortalidade por aids em setores censitários de município brasileiro de grande porte. Método: Foram estudadas três coortes retrospectivas de indivíduos notificados por aids e residentes no município de Campinas, São Paulo, nos períodos de 1980 a 1990 (coorte 1), 1996 a 2000 (coorte 2) e 2001 a 2005 (coorte 3), a fim de identificar a ocorrência do óbito. Foi ajustado um modelo semiparamétrico Bayesiano, empregando o método de Aproximação de Laplace Aninhada e Integrada (INLA), que permitiu obter mapas de risco de óbito nas três coortes estudadas. Resultados: A incidência de óbito nas coortes 1, 2 e 3 foram, respectivamente, 72,73; 32,21 e 13,11%. Os mapas de risco de óbito apontaram tendência de queda da mortalidade e evidenciaram os setores que apresentaram maior e menor risco em cada período. O modelo mostrou que, nas três coortes, os fatores associados ao maior risco de óbito foram: ser do sexo masculino e possuir idade de diagnóstico superior a 49 anos. A orientação homossexual/bissexual foi associada ao menor risco de morrer. Conclusões: Mesmo diante da diminuição do risco de morte por aids nos últimos anos, após o acesso à terapia antirretroviral altamente ativa, a maior incidência se concentra entre os mais pobres nas três coortes estudadas. Os mapas e o fatores de risco obtidos orientam possíveis ações e monitoramento da doença no município.

ABSTRACT: Objective: To analyze the spatial risk of AIDS mortality in census tracts in a large Brazilian city. Method: We studied three retrospective cohorts of individuals with AIDS, who were residents in the city of Campinas, in the State of São Paulo, Brazil. The occurrence of death was analyzed from 1980 to 1990 (cohort 1), 1996 to 2000 (cohort 2), and from 2001 to 2005 (cohort 3). We adjusted a Bayesian semi-parametric model, using the Integrated Nested Laplace Approximation (INLA) method, which allowed for the mapping of mortality risk for the three cohorts. Results: The incidence of death in cohorts 1, 2 and 3 were, respectively, 72.73, 32.21 and 13.11%. The death risk maps showed a tendency of mortality decrease, and presented the sectors with the highest and lowest risk for each period. The model showed that, in the three cohorts, factors associated with the highest risk of death were: being male, and having an age at diagnosis greater than 49 years old. The homosexual/bisexual orientation was associated with lower risk of dying. Conclusions: Even considering the reduction in the risk of death from AIDS in recent years, after access to highly active antiretroviral therapy, the highest incidence was found among the poorest individuals in the three studied cohorts. The maps and risk factors obtained suggest possible actions for monitoring the disease in the city.