The suitability of laboratory-bred Anopheles cracens for the production of Plasmodium vivax sporozoites

Abstract

BackgroundA stenogamous colony of Anopheles cracens (A. dirus B) established 20 years ago in a Thai insectary proved susceptible to Plasmodium vivax. However, routine sporozoite production by feeding on field-collected blood samples has not been described. The setting-up of an A. cracens colony in an insectary on the Thai-Myanmar border and the process of using P. vivax field samples for the production of infectious sporozoites are described.MethodsThe colony was started in 2012 from egg batches that were sent from the Department of Parasitology, Faculty of Medicine, University of Chiang Mai, to the Shoklo Malaria Research Unit (SMRU), on wet filter paper in sealed Petri dishes. From May 2013 to December 2014, P. vivax-infected blood samples collected from patients seeking care at SMRU clinics were used for membrane feeding assays and sporozoite production.ResultsMosquitoes were fed on blood samples from 55 patients, and for 38 (69 %) this led to the production sporozoites. The average number of sporozoites obtained per mosquito was 26,112 (range 328–79,310). Gametocytaemia was not correlated with mosquito infectiousness (p = 0.82), or with the number of the sporozoites produced (Spearman’s ρ = −0.016, p = 0.905). Infectiousness did not vary with the date of collection or the age of the patient. Mosquito survival was not correlated with sporozoite load (Spearman’s ρ = 0.179, p = 0.282).ConclusionConsistent and routine P. vivax sporozoites production confirms that A. cracens is highly susceptible to P. vivax infection. Laboratory-bred colonies of this vector are suitable for experimental transmission protocols and thus constitute a valuable resource.Electronic supplementary materialThe online version of this article (doi:10.1186/s12936-015-0830-0) contains supplementary material, which is available to authorized users.

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Comparison of the Performances of Five Primer Sets for the Detection and Quantification of Plasmodium in Anopheline Vectors by Real-Time PCR

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An adaptable soft-mold embossing process for fabricating optically-accessible, microfeature-based culture systems and application toward liver stage antimalarial compound testing

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