November 27, 2020

I, Science

The science magazine of Imperial College

Liz Zuccala looks at how scientists are looking for drugs to stop sexual development of malaria parasites

mosquito full  Ragnhild BrosvikImperial College researchers have developed a sensitive in vitro technique to screen drugs for their ability to block malaria transmission, making a crucial step in the effort to eradicate a disease that claims over 600,000 lives per year.    Malaria is caused by tiny single-celled parasites from the Plasmodium genus. As an organism with a highly complex and varied life cycle that swaps between mosquito and mammalian hosts, this pathogen presents a major challenge to scientists aiming to develop new strategies to prevent and treat infections. There is no licensed vaccine against malaria and the utility of current anti-malarial drugs is under threat from emerging parasite resistance. As such, research is focused on developing novel ways to tackle this global problem. Central to this effort is the drive to block malaria transmission and thus stop malaria in its tracks.

Malaria is transmitted from person-to-person by the bite of an infected mosquito. When a female Anopheles mosquito takes a blood meal from an infected person, she ingests the parasites, which undergo sexual development in her stomach. The Plasmodium eventually transforms into a version of the parasite that can travel through her body to the salivary glands where they wait to infect into a new host when she feeds again.

Recent research published in Antimicrobial Agents and Chemotherapy by Dr Michael Delves and colleagues describes a new method to test the ability of drugs to inhibit the sexual development of malaria parasites and thus block transmission. Key to their assay is its specific and high-throughput nature – they are able to screen hundreds of drugs at a time for their ability to disrupt parasite development in the mosquito midgut, without having to perform cumbersome and time-consuming experiments with mosquitos themselves. Using this technique they were able to discern crucial information about when and how drugs act on the parasite to block its function, providing a way to develop new therapies which could stop the spread of malaria.

Liz Zuccala is a fourth year PhD student studying Life Sciences

Images: Mosquito – full by Ragnhild Brosvik;