There's currently no vaccine for malaria, despite the fact that the disease infects 214 million people per year and kills about half a million. But scientists have been working on a vaccine for some time. Now, a new study reveals that an experimental malaria vaccine can protect adults from malaria for up to a year.
Doctors and scientists want a vaccine that offers protection for longer than that, but the new study, published Monday in the journal Nature Medicine has shown the longest duration of protection so far. The vaccine, called PfSPZ is developed by the biotech company Sanaria Inc, which is focused on malaria, with the help of National Institutes of Health scientists and University of Maryland School of Medicine researchers.
Malaria is caused by a parasite that infects mosquitoes that then spread it to humans. The disease is characterized by high fevers and flulike symptoms, and in some cases, it is fatal. To test the vaccine in a phase 1 trial, the researchers exposed volunteers to malaria. The volunteers were around 100 people who never had malaria before. Close to 60 of the men and women received the experimental vaccine and about 30 people were not vaccinated. There was also variety in dosage given to some of the volunteers as well as how the vaccine as administered: some people got it intravenously and some got it injected into their muscle. The men and women were then exposed to mosquitoes that were carrying P. falciparum, which is an early stage of the malaria parasite. The PfSPZ vaccine is developed from a weakened P. falciparum strain.
The scientists looked at the blood of the volunteers to understand how protected they were from infection. Ultimately they found that the vaccine offered up to a year of protection for 55% of the men and women. Prior studies of the vaccine had shown it could offer protection for three weeks. While the latest study underlines forward movement in vaccine development, there's still much more research that needs to be done before the vaccine can be offered clinically. Other pharmaceutical companies are also working on vaccines, including some that are especially protective for children.