Mosquitoes are vectors of disease, and one of the deadliest illnesses they carry is that of malaria, which is particularly known to affect young children. When female mosquitoes acquire the malaria parasite (Plasmodium) by drinking the blood of an infected animal or person, they become infectious after roughly 10 days. Once Plasmodium develops, that mosquito will continue to transmit malaria to every person it bites for the rest of its life.
Malaria can spread expansively or in limited extents depending on which vector species is carrying it. In Africa, malaria is usually found in rural areas because that’s where the native mosquito species live and breed. However, a new invasive species, known as Anopheles stephensi, has been infiltrating Africa from its local range in India and nearby countries in the Middle East [1]. Unlike African species, this mosquito is well-adapted to urban environments. This means that it can increase malaria cases within densely populated cities, potentially increasing the most common form of malaria by 50% [2].
In this study, I examined the lifespan of Anopheles stephensi in comparison with those of native African species, since a mosquito’s lifespan directly relates to its success in transmitting disease. Over three months, I raised thousands of mosquitoes in the laboratory to conduct a survival analysis, in addition to measuring the effects of sex and body size on lifespan. The study demonstrated that these enduring species could survive over 30 days, and stresses the importance of future endeavours to shorten this lifespan and reduce malaria cases.
[1] R. Taylor, et al., “Invasive Anopheles stephensi in Africa: insights from Asia,” 2024, Elsevier Ltd. doi: 10.1016/j.pt.2024.06.008.
[2] G. Olatunji et al., “Anopheles stephensi and the impending challenge to malaria eradication in Africa,” 2024, New Microbes New Infect, vol. 58, p. 101232. doi: https://doi.org/10.1016/j.nmni.2024.101232.