Mapping and characterizing areas with high levels of malaria in pregnancy in Brazil: A spatiotemporal analysis

Jamille Gregório Dombrowski; Laura Cordeiro Gomes; Camila Lorenz; Raquel Gardini Sanches Palasio; Paola Marchesini; Sabrina Epiphanio; Claudio Romero Farias Marinho

doi:10.1016/j.lana.2022.100285

Mapping and characterizing areas with high levels of malaria in pregnancy in Brazil: A spatiotemporal analysis

Lancet Reg Health Am. 2022 May 27:12:100285. doi: 10.1016/j.lana.2022.100285. eCollection 2022 Aug.

Authors

Jamille Gregório Dombrowski¹, Laura Cordeiro Gomes¹, Camila Lorenz², Raquel Gardini Sanches Palasio², Paola Marchesini³, Sabrina Epiphanio⁴, Claudio Romero Farias Marinho¹

Affiliations

¹ Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil.
² Department of Epidemiology, School of Public Health, University of São Paulo, São Paulo, Brazil.
³ Department of Transmissible Diseases Surveillance, Ministry of Health, Brasília, Brazil.
⁴ Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil.

Abstract

Background: Malaria in pregnancy (MiP) is a public health problem in the Brazilian Amazon region that requires special attention due to associated serious adverse consequences, such as low birth weight, increased prematurity and spontaneous abortion rates. In Brazil, there have been no comprehensive epidemiological studies of MiP. In this study, we aimed to explore the spatial and spatiotemporal patterns of MiP in Brazil and epidemiologically characterize this population of pregnant women over a period of 15 years.

Methods: We performed a national-scale ecological analysis using a Bayesian space-time hierarchical model to estimate the incidence rates of MiP between 1 January 2004 and 31 December 2018. We mapped the high-incidence clusters among pregnant women aged 10-49 years old using a Poisson model, and we characterized the population based on data from the Epidemiological Surveillance Information System for Malaria (SIVEP-Malaria).

Findings: We consolidated the data of 61,833 women with MiP in Brazil. Our results showed a reduction of 50·1% (95% CI: 47·3 to 52·9) in the number of malaria cases over the period analysed, with Plasmodium vivax malaria having the highest incidence. MiP was widely distributed throughout the Amazon region, and spatial and spatiotemporal analyses revealed statistically significant clusters in some municipalities of Amazonas, Acre, Rondônia and Pará. In addition, we observed that younger pregnant women had a higher risk of infection, and the administration of appropriate treatment requires more attention.

Interpretation: This nationwide study provides robust evidence that, despite the reduction in the number of MiP cases in the country, it remains a serious public health problem, especially for young pregnant women. Our analyses highlight focus areas for strengthening interventions to control and eliminate MiP.

Funding: FAPESP and CNPq - Brazil.

Keywords: Brazil; Epidemiology; Malaria; P. falciparum; P. vivax; Pregnancy.