Declining malaria parasite prevalence and trends of asymptomatic parasitaemia in a seasonal transmission setting in north-western Burkina Faso between 2000 and 2009–2012

Malaria Journal

Research

Boubacar Coulibaly¹  Guillaume Compaoré¹  Ali Sié¹  Carolin Geiger²  Michael Lanzer²  Thomas Jänisch²  Hani Kartini Agustar²  Heiko Becher³ 

[1] Centre de Recherche en Santé à Nouna, BP02, Nouna, Burkina Faso;Department for Infectious Diseases, Parasitology, University Hospital Heidelberg, Im Neuenheimer Feld 324, 69120, Heidelberg, Germany;Institute for Public Health, University Hospital Heidelberg, Im Neuenheimer Feld 324, 69120, Heidelberg, Germany;

关键词: Malaria;    Transmission;    Parasite prevalence;    Parasite density;    Plasmodium falciparum;    Mixed infections;    Asymptomatic parasitaemia;    Seasonal transmission;    Clinical malaria;    Burkina Faso;   

DOI  :  10.1186/1475-2875-12-27

 received in 2012-12-07, accepted in 2013-01-14,  发布年份 2013

来源: Springer

【 摘 要 】

BackgroundMalaria transmission was reported to have declined in some East African countries. However, a comparable trend has not been confirmed for West Africa. This study aims to assess the dynamics of parasite prevalence and malaria species distribution over time in an area of highly seasonal transmission in Burkina Faso. The aim was also to compare frequency of asymptomatic parasitaemia between wet and dry season by parasite density status and age group.MethodsDuring the years 2009–2012, six cross-sectional studies were performed in the rural village Bourasso in the Nouna Health District in north-west Burkina Faso. In subsequent rainy and dry seasons blood samples were collected to assess the parasite prevalence, species, density and clinical parameters. In total, 1,767 children and adults were examined and compared to a baseline collected in 2000.ResultsThe microscopical parasite prevalence (mainly P. falciparum) measured over the rainy seasons decreased significantly from 78.9% (2000) to 58.4%, 55.9% and 49.3%, respectively (2009–2011; p <0.001). The frequency of Plasmodium malariae infections (mono- and co-infections) decreased parallel to the overall parasite prevalence from 13.4% in 2000 to 2.1%, 4.1% and 4.7% in 2009–2011 (p <0.001). Comparing parasite-positive subjects from the rainy season versus dry season, the risk of fever was significantly reduced in the dry season adjusting for parasite density (grouped) and age group.ConclusionsThe results of this study suggest a decline of malaria transmission over the rainy seasons between 2000 and 2009–2011 in the region of Nouna, Burkina Faso. The decreased transmission intensity was associated with lower prevalence of P. malariae infections (both mono-infections and co-infections). Asymptomatic parasitaemia was more frequent in the dry season even adjusting for parasite density and age group in a multivariate regression. Possible reasons for this observation include the existence of less pathogenic Plasmodium falciparum genotypes prevailing in the dry season, or the effect of a reduced incidence density during the dry season.

【 授权许可】

Unknown   
© Geiger et al.; licensee BioMed Central Ltd. 2013. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.