Patrick Duffy began his career in 1991 at the Walter Reed Army Institute of Research. Scientists were just a few years away from testing a vaccine that would prevent malaria. The World Health Organization recommended that the malaria intervention be used for children below 5 years of age in Africa, thirty years after the research was completed. Mosquirix is also known as the RTS,S vaccine. It's the first vaccine that protects against parasites.
Duffy is now the head of the Laboratory of Malaria Imology and Vaccinology at National Institute of Allergy and Infectious Diseases. He is excited about the potential for it to lower the death toll of a deadly disease that kills over 400,000 people each year. He is well aware, however, that this vaccine won't be a panacea. He says that this vaccine prevents children from getting malaria. It doesn't prevent the transmission of the parasite to humans from mosquitoes, and it doesn't protect all who are at risk. But what about pregnant women? He asks, "What about elimination?" This seems like a foundation upon which we can make improvements.
GlaxoSmithKline (GSK), a pharmaceutical company, first developed RTS,S in 1980s. It was intended for children under 5 years old, who account for more than 65 percent of all malaria deaths. As we age, our immunity to the parasite develops. Adults don't become as sick as children. This vaccine will speed up the process and give protection to children until they have stronger immune systems.
It took a while to test the vaccine. GSK collaborated with Walter Reed, the Bill and Melinda Gates Foundation and clinics in seven African nations to conduct clinical trials. After Phase III clinical trials that GSK conducted from 2009 to 2011, the European Medicines Agency deemed the vaccine safe and effective. It was found to be 50 percent effective in preventing serious illnesses. Officials at WHO were not confident that the vaccine would work in real-world settings. The vaccine is administered as four shots over 18 months. GSK also ran a pilot program to test the product in Ghana and Malawi in 2019.
The WHO recommends that the vaccine be approved by each country's health ministers. It takes time to scale up manufacturing in order to produce millions of doses and organize national health systems to distribute them. Also, it is difficult to get financial assistance from non-profits and other countries. Ashley Birkett, director at PATH, the nonprofit that developed the vaccine, said there is still much to be done.
Malaria is a complex parasite that has evolved with humans over thousands of years. Malaria is transmitted by mosquitoes, not through respiratory viruses such as the flu. They carry the parasite to other people by biting them. The SARS-CoV-2 virus contains around 10 genes, which code for 29 proteins. Plasmodium falciparum is one of five malaria parasites. It has a larger genome, which codes for more than 5,000 proteins.
Complex life cycles are also characteristic of the parasite. Infected mosquitoes bite people and tiny spores, called sporozoites, enter the bloodstream. They travel to the liver where they multiply by breaking down themselves. These spores then travel from the liver to the bloodstream, heart, lungs and bloodstream. They infect red blood cell and cause flu-like symptoms like nausea and vomiting. In severe cases, malaria can cause brain damage, seizures, breathing difficulty, and organ failure.