Two medications can prevent the transmission of malaria

Are there any new ways of controlling malaria?

Malaria is a life-threatening disease that is particularly prevalent in African countries. Researchers now found that two medicines could be used to safely and effectively prevent the transmission of malaria.

The researchers from the University of California, San Francisco found in their study that two drugs could prevent the spread of the most common form of malaria in Africa. The physicians published the results of their study in the English-language journal "The Lancet Infectious Diseases".

Also drug-resistant form can be treated

The use of two drugs could in the future help to reduce the spread of a type of malaria called P. falciparum, including their drug-resistant forms, say the experts. This could be a significant step forward in the eradication of the disease.

Millions of people could be protected from malaria

Although both drugs have been in existence for more than half a century, this is the first time that the exciting and impressive effects of each of these drugs on malaria transmission have been so clearly demonstrated in a comparative study, study author Professor Dr. Roly Gosling of the University of California, San Francisco. The efficacy of antimalarial drugs used for seasonal so-called malaria chemoprevention can be significantly improved. The discovery has the potential to end the threat of malaria to millions of people across West Africa.

How does malaria spread??

Malaria has different forms. The disease spreads through a recurrent cycle in which it is transmitted from mosquitoes to humans and back again, the experts explain. When a person is stung by an infected mosquito, malaria parasites migrate through the liver into the bloodstream, where they then circulate for several weeks. The majority of parasites replicate in the red blood cells in asexual forms. But a small percentage develops in male and female cells, called gametocytes. These play an important role in the transmission of the disease to mosquitoes.

Transmission on mosquitoes must be prevented

Because these gametocytes are not killed by the antimalarial drugs used to treat P. falciparum (the most common form of malaria in Africa), people can transmit the infection to mosquitoes for weeks after treatment, scientists say. For this reason, something must be added to the treatment scheme to block such transmission.

How do primaquine and methylene blue work??

The current study examined the safety and efficacy of primaquine, which has been used for decades to treat another form of malaria (P. vivax). In addition, a laboratory dye called methylene blue has been studied, which has been used for almost a century to distinguish dead from living cells. When injected into the bloodstream, methylene blue also acts as an antimalarial drug. The researchers found that each of these compounds, when added to various antimalarial regimens, prevented the gametocytes of P. falciparum malaria parasites from getting into mosquitoes by infected humans.

Further research is needed

"Patients who did not receive these medications could still get mosquitoes infected for at least a week after treatment," explains Dr. Alassane Dicko in a press release from the University of California, San Francisco. The researchers say the findings could accelerate the elimination of malaria in the affected countries. However, further studies are still needed to identify the optimal scenarios in which these drugs can be used.

Transmission is blocked quickly

The researchers conducted a Phase 2 study to compare the efficacy of the two compounds in preventing the transfer of gametocytes in asymptomatic malaria. They found that the addition of a single dose of primaquine to a sulfadoxine-pyrimethamine and amodiaquine treatment or the addition of three doses of methylene blue to a dihydroartemisinin piperaquine treatment resulted in an almost complete blockage of transmission within 48 hours. This could become very important in the future because WHO warns against a major malaria return. (As)