THE TRANSMISSION EFFICIENCY OF PLASMODIUM YOELII INFECTED MOSQUITOES

Plasmodium yoelii;malaria;transmission dynamics;entomological inoculation rate;EIR;force of human infection;not listed

Aleshnick, MayaSinnis, Photini ;

Johns Hopkins University

关键词: Plasmodium yoelii;    malaria;    transmission dynamics;    entomological inoculation rate;    EIR;    force of human infection;    not listed;   

Others  :  https://jscholarship.library.jhu.edu/bitstream/handle/1774.2/38066/ALESHNICK-THESIS-2015.pdf?sequence=1&isAllowed=y

瑞士|英语

来源: JOHNS HOPKINS DSpace Repository

【 摘 要 】

Malaria is a life-threatening infectious disease caused by the Plasmodium parasite. Nearly half of the global population is at risk of acquiring malaria and there are approximately 500,000 deaths and 200 million cases annually. The infective form of the parasite, the sporozoite, is transmitted by the female Anopheles mosquito as she probes on a human host in search of a blood meal. Although it has been over 100 years since Ronald Ross discovered that Anopheles mosquitoes are the vector for the parasite, we still do not fully understand the early transmission dynamics of Plasmodium. One aspect that is poorly described is the probability of developing a blood stage infection after the bite of an infected mosquito. The entomological inoculation rate estimates the number of infected bites that an individual receives, but at present there is no understanding of the likelihood that sporozoites inoculated by a bite will successfully infect the host. This work provides the first laboratory estimate of the proportion of infected bites to a naïve host that result in a blood stage infection. In addition, four factors that may influence the transmission efficiency—the intensity of salivary gland infection, the duration of probing, the anatomical location on the host exposed to the mosquito bite, and the success of the mosquito in acquiring a blood meal—are considered. Using the rodent parasite Plasmodium yoelii in Anopheles stephensi mosquitoes, we determined that the transmission efficiency of a single mosquito bite is 21%. Further, the proportion of bites that result in an infection is not dependent on probe time, probe location, or acquisition of a blood meal; however a significantly greater probability of blood stage infection is present when the salivary glands of the probing mosquito are heavily infected.