Malaria is a fatal disease caused by parasites transmitted to humans through the bites of infected women. Anopheles mosquitoes. It is preventable and curable. There are five species of parasites that cause malaria in humans, and two of them – Plasmodium falciparum and Plasmodium vivax – pose the greatest threat.
According to the World Health Organization, WHO, almost half of the world’s population was at risk of malaria in 2022. While sub-Saharan Africa bears a disproportionate share of the global malaria burden, WHO regions of Southeast Asia, the Eastern Mediterranean, Western Pacific and the Americas are also reporting significant numbers of cases and deaths.

How to “catch” malaria?

Malaria is primarily transmitted to humans through the bites of infected female Anopheles mosquitoes. Blood transfusions and contaminated needles can also transmit malaria. Early symptoms may be mild, similar to many febrile illnesses, and difficult to recognize as malaria. Without treatment, P. falciparum malaria can progress to severe illness and death within 24 hours.
The infection is caused by a parasite and is not spread from person to person. Symptoms can be mild or life-threatening. Mild symptoms include fever, chills and headache. Serious symptoms include fatigue, confusion, seizures and difficulty breathing. Infants, children under 5 years old, pregnant women, travelers, and people living with HIV or AIDS are at higher risk of serious infection.
Malaria can be prevented by avoiding mosquito bites and taking medication. Treatments can prevent mild cases from getting worse.
Scientists recently developed a new malaria vaccination strategy that boosts immunity through bites from mosquitoes carrying a genetically modified version of the parasite that causes malaria. In one trial, the new approach reduced participants’ susceptibility to malaria, potentially paving the way for more effective ways to stop the disease.

The study published recently in “The New England Journal of Medicine” exposed participants to bites from mosquitoes carrying a modified version of the parasite Plasmodium falciparum, which causes malaria. In humans, the parasites travel to the liver and then infect red blood cells. Parasites were designed to stop growing shortly after their introduction into humans. Nearly 90% of participants exposed to the engineered parasites avoided contracting the disease after being bitten by malaria mosquitoes.
Julius Hafalla, an immunologist at the London School of Hygiene & Tropical Medicine, said: “These results represent a significant step forward in malaria vaccine development. The current global burden of malaria makes the development of more effective vaccines a key priority.
Symptoms: Symptoms usually appear 10 to 15 days after the bite of an infected mosquito. Early symptoms include fever, headache and chills. Serious symptoms include fatigue, confusion, seizures and difficulty breathing.
Transmission: Malaria is spread through the bite of infected female Anopheles mosquitoes. It can also be transmitted through blood transfusions and contaminated needles.
Diagnosis: A doctor may suspect malaria based on your travel history, symptoms and physical exam. To confirm, they may order lab tests to see if the parasite is in your blood.
Treatment: Malaria is treatable, and starting treatment as early as possible can often prevent serious illness and death. Chloroquine is often used as an antimalarial drug, but there are also treatments for infections resistant to chloroquine.

Malaria vaccines:

So far, there are two approved malaria vaccines. Both aim to provide long-term immunity by producing antibodies that prevent malaria parasites from infecting liver cells, as well as targeting breakthrough infections. However, vaccines are only about 75% effective and require booster shots. This is why immunologists continue to explore alternative strategies to combat the disease.
One of these approaches is to use genetically modified parasites. The research team previously conducted a trial to examine the effectiveness of a modified malaria parasite, called GA1, designed to stop growing about 24 hours after infection in humans. But the GA1 parasite only protected a few participants against malaria, leading the team to engineer a second parasite, GA2. GA2 is designed to stop growing around six days after infection, during the crucial period when parasites are replicating in human liver cells.
The researchers tested whether exposure to GA1 or GA2 could help humans develop immunity to malaria. They exposed participants to the bites of 50 mosquitoes; Ten participants were bitten by mosquitoes infected with GA1 parasites and ten were bitten by GA2 parasites. Three weeks later, they exposed the participants to malaria-carrying mosquitoes. Just before exposure to these mosquitoes, both groups of participants had higher levels of antibodies than before. One in eight participants (13%) bitten by GA1 parasites did not contract malaria, compared to 89% in the GA2 group. Aside from the itching associated with mosquito bites, side effects were limited.
The researchers now want to replicate their results in a larger trial.