Challenges for malaria elimination in Brazil

Abstract

Brazil currently contributes 42 % of all malaria cases reported in the Latin America and the Caribbean, a region where major progress towards malaria elimination has been achieved in recent years. In 2014, malaria burden in Brazil (143,910 microscopically confirmed cases and 41 malaria-related deaths) has reached its lowest levels in 35 years, Plasmodium falciparum is highly focal, and the geographic boundary of transmission has considerably shrunk. Transmission in Brazil remains entrenched in the Amazon Basin, which accounts for 99.5 % of the country’s malaria burden. This paper reviews major lessons learned from past and current malaria control policies in Brazil. A comprehensive discussion of the scientific and logistic challenges that may impact malaria elimination efforts in the country is presented in light of the launching of the Plan for Elimination of Malaria in Brazil in November 2015. Challenges for malaria elimination addressed include the high prevalence of symptomless and submicroscopic infections, emerging anti-malarial drug resistance in P. falciparum and Plasmodium vivax and the lack of safe anti-relapse drugs, the largely neglected burden of malaria in pregnancy, the need for better vector control strategies where Anopheles mosquitoes present a highly variable biting behaviour, human movement, the need for effective surveillance and tools to identify foci of infection in areas with low transmission, and the effects of environmental changes and climatic variability in transmission. Control actions launched in Brazil and results to come are likely to influence control programs in other countries in the Americas.

Reactive Case Detection for Plasmodium vivax Malaria Elimination in Rural Amazonia

“…This vast region, with 60% of the country's territory but only 13% of its total population, accounts for 99.5% of all malaria cases diagnosed in Brazil; 84% of them are due to P . vivax [7]. …”

Experiential knowledge, suffering, and vicissitudes of having malaria in the Brazilian Amazon: An ethnographic study

“…This study also documents research participants' perception of the low effectiveness of biomedical diagnosis because of the multiple times that they had to repeat the blood smear test. Although the biomedical literature reports the difficulty in identifying malaria parasites using current diagnostic methods (Ferreira and Castro 2016), studies have often overlooked people's struggles with such diagnostic technologies. This study, in contrast, described the ups and downs of individuals who agonized until the disease was confirmed.…”

Allele-specific antibodies to Plasmodium vivax merozoite surface protein-1: prevalence and inverse relationship to haemoglobin levels during infection

“…Although the total number of confirmed malaria cases and deaths in the region has been decreased in the last decades, P. vivax infections in Brazil still account for 42% of all cases and half of the deaths due to malaria registered in the Americas [1]. Several potential challenges may impact the elimination efforts in Brazil where P. vivax accounts for more than 80% of diagnosed malarial infections [2] and cases of severe disease due to this species has been reported in the Amazon endemic region [3–5]. Therefore, the development of an effective malaria vaccine is likely to contribute to a reduction of the disease burden in endemic populations.…”