Entomological aspects and the role of human behaviour in malaria transmission in a highland region of the Republic of Yemen

Malaria Journal

Research

Ralph E. Harbach¹  Andrew G. Briscoe¹  Ahmed Azazy²  Louise Kelly-Hope³  Guy Barnish⁴  Philip J. McCall⁴  Samira M. A. Al-Eryani⁵ 

[1] Department of Life Sciences, Natural History Museum, Cromwell Road, London, UK;Department of Medical Parasitology, Faculty of Medicine and Health Sciences, University of Yemen, Sana’a, Yemen;Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, UK;Department of Vector Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, UK;Department of Vector Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, UK;Department of Medical Parasitology, Faculty of Medicine and Health Sciences, University of Yemen, Sana’a, Yemen;

关键词: Arabia;    Plasmodium falciparum;    Anopheles;    Arabiensis;    Sergentii;    Sporozoite;    EIR;    Taiz;    Vector;    Mosquito;    Surveillance;   

DOI  :  10.1186/s12936-016-1179-8

 received in 2016-01-13, accepted in 2016-02-17,  发布年份 2016

来源: Springer

【 摘 要 】

BackgroundThe Republic of Yemen has the highest incidence of malaria in the Arabian Peninsula, yet little is known of its vectors or transmission dynamics.MethodsA 24-month study of the vectors and related epidemiological aspects of malaria transmission was conducted in two villages in the Taiz region in 2004–2005.ResultsCross-sectional blood film surveys recorded an overall malaria infection rate of 15.3 % (250/1638), with highest rates exceeding 30 % in one village in May and December 2005. With one exception, Plasmodium malariae, all infections were P.falciparum. Seven Anopheles species were identified among 3407 anophelines collected indoors using light traps (LT) and pyrethrum knockdown catches (PKD): Anopheles arabiensis (86.9 %), An. sergentii (9 %), An. azaniae, An. dthali, An. pretoriensis, An. coustani and An. algeriensis. Sequences for the standard barcode region of the mitochondrial COI gene confirmed the presence of two morphological forms of An. azaniae, the typical form and a previously unrecognized form not immediately identifiable as An. azaniae. ELISA detected Plasmodium sporozoites in 0.9 % of 2921 An. arabiensis (23 P. falciparum, two P. vivax) confirming this species as the primary malaria vector in Yemen. Plasmodium falciparum sporozoites were detected in An. sergentii (2/295) and a single female of An. algeriensis, incriminating both species as malaria vectors for the first time in Yemen. A vector in both wet and dry seasons, An. arabiensis was predominantly anthropophilic (human blood index = 0.86) with an entomological inoculation rate of 1.58 infective bites/person/year. Anopheles sergentii fed on cattle (67.3 %) and humans (48.3; 20.7 % mixed both species), but only 14.7 % were found in PKDs, indicating predominantly exophilic behaviour. A GIS analysis of geographic and socio-economic parameters revealed that An. arabiensis were significantly higher (P < 0.001) in houses with televisions, most likely due to the popular evening habit of viewing television collectively in houses with open doors and windows.ConclusionsThe predominantly indoor human biting vectors recorded in this study could be targeted effectively with LLINs, indoor residual spraying and/or insecticide-treated window/door curtains reinforced by education to instil a perception that effective and affordable malaria prevention is achievable.

【 授权许可】

CC BY   
© Al-Eryani et al. 2016