[HTML][HTML] Case report: Successful sporozoite challenge model in human volunteers with Plasmodium vivax strain derived from human donors

S Herrera, O Fernández, MR Manzano… - The American journal …, 2009 - ncbi.nlm.nih.gov
S Herrera, O Fernández, MR Manzano, B Murrain, J Vergara, P Blanco, R Palacios…
The American journal of tropical medicine and hygiene, 2009ncbi.nlm.nih.gov
Successful establishment of a Plasmodium vivax sporozoite challenge model in humans is
described. Eighteen healthy adult, malaria-naïve volunteers were randomly allocated to
Groups A–C and exposed to 3±1, 6±1, and 9±1 bites of Anopheles albimanus mosquitoes
infected with P. vivax, respectively. Seventeen volunteers developed signs and symptoms
consistent with malaria, and geometric mean prepatent periods of 11.1 days (9.3–11) for
Group A; 10.8 days (9.8–11.9) for Group B; and 10.6 days (8.7–12.4) for Group C, with no …
Abstract
Successful establishment of a Plasmodium vivax sporozoite challenge model in humans is described. Eighteen healthy adult, malaria-naïve volunteers were randomly allocated to Groups A–C and exposed to 3±1, 6±1, and 9±1 bites of Anopheles albimanus mosquitoes infected with P. vivax, respectively. Seventeen volunteers developed signs and symptoms consistent with malaria, and geometric mean prepatent periods of 11.1 days (9.3–11) for Group A; 10.8 days (9.8–11.9) for Group B; and 10.6 days (8.7–12.4) for Group C, with no statistically significant difference among groups (Kruskal-Wallis, P= 0.70). One volunteer exposed to eight mosquito bites did not develop a parasitemia. No differences in parasite density were observed and all individuals successfully recovered after anti-malarial treatment. None of the volunteers developed parasite relapses within an 18-month follow-up. In conclusion, malaria-naive volunteers can be safely and reproducibly infected with bites of 2–10 An. albimanus mosquitoes carrying P. vivax sporozoites. This challenge method is suitable for vaccine and anti-malarial drug testing.
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