🦟 New medication kills mosquitoes through the blood they suck

• A medication approved for rare genetic diseases, proves to kill malaria-carrying mosquitoes when they suck blood from people who have taken the medicine.
• The mosquitoes die within 24 hours after sucking blood containing nitisinone, which is faster than with previously tested medications.
• A person taking three daily doses (1 mg/kg) of nitisinone could maintain mosquito-killing levels in their blood for up to sixteen days.

Mosquitoes kill over a million people each year

Mosquitoes are some of the world's deadliest creatures. These small insects spread diseases such as malaria, dengue fever, and Zika virus, which together cause over a million deaths annually. Traditionally, insecticides have been used to control mosquito populations, but these have significant disadvantages: they can harm other insects, contribute to environmental damage, and become increasingly ineffective as mosquitoes develop resistance.

Medication makes blood toxic to mosquitoes

A new study shows that mosquitoes can be poisoned by the blood of people taking the medication nitisinone. The drug is already approved by the US Food and Drug Administration for treating certain rare genetic disorders.

The concept of poisoning mosquitoes through their blood meals is not entirely new. Previously, researchers have investigated ivermectin, a widely used antiparasitic drug. When a mosquito bites a person treated with ivermectin, the drug enters the mosquito and kills it. However, ivermectin has limitations - it takes up to four days to kill mosquitoes and its effects diminish quickly in the bloodstream.

Nitisinone disrupts mosquito digestion

Nitisinone offers a more promising alternative. Unlike traditional insecticides, which typically target the mosquito's nervous system, nitisinone disrupts a crucial enzyme (HPPD) that mosquitoes need to digest their blood meal. Without this enzyme, mosquitoes experience a metabolic shutdown, leading to death within 24 hours - much faster than with ivermectin.

Nitisinone is effective at much lower doses than previously expected. Even blood from people taking small amounts of the drug proved lethal to mosquitoes. This means that individuals in malaria-endemic regions could potentially take a safe low dose of nitisinone, turning their blood into a mosquito-killing agent without significant side effects.

Several advantages compared to other methods

Since nitisinone targets a completely different biological pathway from traditional insecticides, mosquitoes have no existing resistance to it. Additionally, it is equally lethal to older mosquitoes as to younger ones, which is important since malaria is primarily transmitted by older female mosquitoes that have lived long enough to pick up the parasite from an infected person.

Nitisinone stays in the bloodstream much longer than ivermectin. According to pharmacokinetic modeling, a person taking three daily doses of nitisinone (1 mg/kg) would maintain mosquito-killing levels in their blood for up to sixteen days - six days longer than ivermectin. This extended protection can reduce the frequency of dosing, making it easier to implement as a public health strategy.

Further research required

Although the results of this study are very promising, further research is needed before nitisinone can be widely used for mosquito control. The drug is currently approved for treating certain rare metabolic disorders, but its long-term safety in healthy individuals needs to be carefully studied. Researchers must also ensure that nitisinone does not interfere with other malaria treatments.

If it proves safe and effective, nitisinone could be used in various ways. People in malaria hotspots could take the drug during peak transmission seasons to reduce mosquito populations. It could complement bed nets, insecticides, and antimalarial medications to create a multi-pronged strategy against malaria, and it could be given to livestock to reduce mosquito populations in rural areas.