Malaria in selected non-Amazonian countries of Latin America

Abstract

Approximately 170 million inhabitants of the American continent live at risk of malaria transmission. Although the continent’s contribution to the global malaria burden is small, at least 1 to 1.2 million malaria cases are reported annually. Sixty per cent of the malaria cases occur in Brazil and the other 40% are distributed in 20 other countries of Central and South America. Plasmodium vivax is the predominant species (74.2 %) followed by P. falciparum (25.7 %) and P. malariae (0.1%), and no less than 10 Anopheles species have been identified as primary or secondary malaria vectors. Rapid deforestation and agricultural practices are directly related to increases in Anopheles species diversity and abundance, as well as in the number of malaria cases. Additionally, climate changes profoundly affect malaria transmission and are responsible for malaria epidemics in some regions of South America. Parasite drug resistance is increasing, but due to bio-geographic barriers there is extraordinary genetic differentiation of parasites with limited dispersion. Although the clinical spectrum ranges from uncomplicated to severe malaria cases, due to the generally low to middle transmission intensity, features such as severe anemia, cerebral malaria and other complications appear to be less frequent than in other endemic regions and asymptomatic infections are a common feature. Although the National Malaria Control Programs (NMCP) of different countries differ in their control activities these are all directed to reduce morbidity and mortality by using strategies like health promotion, vector control and impregnate bed nets among others. Recently, international initiatives such as the Malaria Control Program in Andean-country Border Regions (PAMAFRO) (implemented by the Andean Organism for Health (ORAS) and sponsored by The Global Fund to Fight AIDS, Tuberculosis and Malaria (GFATM)) and The Amazon Network for the Surveillance of Antimalarial Drug Resistance (RAVREDA) (sponsored by the Pan American Health Organization/World Health Organization (PAHO/WHO) and several other partners), have made great investments for malaria control in the region. We describe here the current status of malaria in a non-Amazonian region comprising several countries of South and Central America participating in the Centro Latino Americano de Investigación en Malaria (CLAIM), an International Center of Excellence for Malaria Research (ICEMR) sponsored by the National Institutes of Health’s (NIH) National Institute of Allergy and Infectious Diseases (NIAID).

Severe and benign Plasmodium vivax malaria in Emberá (Amerindian) children and adolescents from an endemic municipality in Western Colombia

“…In this series, although the frequency was low, the number of mixed malaria cases (due to P. vivax and P. falciparum, 5.4%) was quite high compared to other studies in Latin America, which usually have reported less than 2% [7,[26][27][28]. However, the mixed malaria cases were those that most frequently presented complications and required the patient to be hospitalized in this study (crude OR = 5.535; 95%CI 1.81-16.9).…”

Malaria-Related Anemia in Patients from Unstable Transmission Areas in Colombia

“…Three malaria-endemic settings with different transmission patterns were selected: Tierralta (Department of Có rdoba) in the northern region of Colombia, Quibdó (Department of Chocó ) in the western region, and Tumaco (Department of Nariñ o) in the southwest region along the Pacific coast. Both P. vivax and P. falciparum are transmitted in these regions in different proportions, with an unstable endemic pattern 8,12 ( Figure 1). Tierralta has a population of approximately 90,000 inhabitants, with most inhabitants characterized as mestizos and an indigenous minority (Emberá Katío); the predominant malaria parasite species in this region is P. vivax (83%).…”

“…2,[4][5][6][7] The human population in this region has a different genetic background, P. vivax is the most prevalent malaria parasite species, malaria transmission intensity is low and unstable, and the young adult population seems to be at higher risk for malarial anemia than children. 8,9 As a consequence of this complexity, malaria and anemia exhibit epidemiological characteristics that seem to be unique to the region and remain poorly understood. In 2012, approximately 469,000 malaria cases (microscopically confirmed) were reported on the South American continent, mainly caused by P. vivax (approximately 74%) and P. falciparum (approximately 26%).…”

Maternal Clinical Findings in Malaria in Pregnancy in a Region of Northwestern Colombia

“…6 There have been few clinical studies that investigated the effects of malaria in pregnant women in malaria-endemic regions of Latin America, where infections by Plasmodium vivax are more prevalent. 7 A search performed in the electronic databases PUBMED, MEDLINE, and BIREME in October of 2012, using the MeSH terms malaria, pregnancy, clinical findings, and Latin America, resulted in four publications on the subject. [8][9][10][11] To characterize the clinical and laboratory findings of malaria in pregnancy (MIP) in a non-Amazonian endemic region of Colombia, we enrolled pregnant women who had been diagnosed with infection by Plasmodium spp.…”