Transmission efficiency of Plasmodium vivax at low parasitaemia

Malaria Journal

Research

Liwang Cui¹  Wanlapa Roobsoong²  Chayanut Suansomjit²  Nongnuj Maneechai²  Jetsumon Sattabongkot²  Piyarat Sripoorote²  Chalermpon Kumpitak²  Thitiporn Surit³  Wang Nguitragool⁴ 

[1] Department of Internal Medicine, Morsani College of Medicine, University of South Florida, 33612, Tampa, FL, USA;Mahidol Vivax Research Unit, Faculty of Tropical Medicine, Mahidol University, 420/6 Ratchawithi Rd, Ratchathewi, 10400, Bangkok, Thailand;Mahidol Vivax Research Unit, Faculty of Tropical Medicine, Mahidol University, 420/6 Ratchawithi Rd, Ratchathewi, 10400, Bangkok, Thailand;Department of Clinical Tropical Medicine, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand;Mahidol Vivax Research Unit, Faculty of Tropical Medicine, Mahidol University, 420/6 Ratchawithi Rd, Ratchathewi, 10400, Bangkok, Thailand;Department of Molecular Tropical Medicine and Genetics, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand;

关键词: Plasmodium vivax;    Transmission;    Infectivity;    Gametocyte;    Malaria;    Anopheles;    Asymptomatic;    Oocyst;   

DOI  :  10.1186/s12936-022-04435-9

 received in 2022-08-11, accepted in 2022-12-27,  发布年份 2022

来源: Springer

【 摘 要 】

BackgroundPlasmodium vivax is responsible for much of malaria outside Africa. Although most P. vivax infections in endemic areas are asymptomatic and have low parasite densities, they are considered a potentially important source of transmission. Several studies have demonstrated that asymptomatic P. vivax carriers can transmit the parasite to mosquitoes, but the efficiency has not been well quantified. The aim of this study is to determine the relationship between parasite density and mosquito infectivity, particularly at low parasitaemia.MethodsMembrane feeding assays were performed using serial dilutions of P. vivax-infected blood to define the relationship between parasitaemia and mosquito infectivity.ResultsThe infection rate (oocyst prevalence) and intensity (oocyst load) were positively correlated with the parasite density in the blood. There was a broad case-to-case variation in parasite infectivity. The geometric mean parasite density yielding a 10% mosquito infection rate was 33 (CI 95 9–120) parasites/µl or 4 (CI 95 1–17) gametocytes/µl. The geometric mean parasite density yielding a 50% mosquito infection rate was 146 (CI 95 36–586) parasites/µl or 13 (CI 95 3–49) gametocytes/µl.ConclusionThis study quantified the ability of P. vivax to infect Anopheles dirus at over a broad range of parasite densities. It provides important information about parasite infectivity at low parasitaemia common among asymptomatic P. vivax carriers.

【 授权许可】

CC BY   
© The Author(s) 2023

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