Scientists have discovered a naturally occurring type of bacteria that can aid in the prevention of malaria transmission from mosquitos to people.

The accidental discovery was made after a mosquito colony in one experiment did not develop the malaria parasite.

The bacterium, according to the experts, might be a new tool for combating one of the world's oldest infections, which kills 600,000 people each year. Trials are currently undergoing to assess the safety of the bacteria. 

Scientists at a GSK pharmaceutical company-run research center in Spain made the finding after noting that a colony of mosquitos employed for medication development had ceased spreading malaria.

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Dr. Janneth Rodrigues, who led the program, expressed, "The infection rate in the mosquitoes started dwindling and so by the end of the year the mosquitoes just would not be infected with the malaria parasite."

The scientists kept the samples from their 2014 experiment frozen and returned to them two years later to investigate what had occurred.

Further research indicated that a naturally occurring strain of bacteria known as TC1 has prevented the growth of malaria parasites in the guts of mosquitos.

Rodrigues said, "Once it colonizes the mosquito, it lasts for the entire lifespan," adding, "And we found out that, yes, it is the bacteria which was responsible for reducing transmission in those mosquitoes."

According to new research published in Science magazine, the bacteria can lower a mosquito's parasite load by up to 73%.

The bacterium operates by secreting harmane, a tiny chemical that suppresses the early stages of the malaria parasite's growth in the mosquito's stomach.

GSK scientists found, in collaboration with Johns Hopkins University, that harmane may be consumed orally by the mosquito if combined with sugar or absorbed via its cuticle on touch.

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This opens the door to treating surfaces in regions where insects congregate with the active chemical.

More trials are currently being conducted at the MosquitoSphere enclosed field research facility in Burkina Faso to see how successful and safe it would be to utilize harmane at scale in the real world.

Scientists believe that by turning this bacteria-based intervention into a product, they may soon have another tool in their arsenal to combat one of the world's oldest illnesses.

Malaria kills around 620,000 individuals each year, the majority of whom are children under the age of five. Vaccines have now been produced, but their implementation in Africa is still in its early phases.

The latest discovery, according to Gareth Jenkins of the organization Malaria No More, is encouraging.

"Malaria kills a child every minute. Significant progress has been made in reducing the global burden of malaria, but to get us back on track we need new and innovative tools in the arsenal," Jenkins noted.

"With a strong innovation pipeline, it is possible to end the threat of malaria in our lifetimes."