Major Landmark in a 100-Year Search for a Malaria Vaccine

In one of the greatest global health milestones of our time, the World Health Organization has approved the widespread distribution of the world’s first malaria vaccine. This move, say researchers and public health groups, is a historic moment in the battle against malaria—a preventable and treatable disease that kills over 400 000 people a year. In Africa, the majority of these victims are children under the age of 5.

The endorsed vaccine, called Mosquirix, is the first and only treatment on the market shown to reduce the risk of infection and death in young children. The malarial parasite, P. falciparum, tops the list as the most deadly parasitic pathogen and is spread via a female Anopheles mosquito bite.

From an immunological perspective, malaria is particularly difficult to treat. The parasite has evolved clever ways of evading the immune system. For example, malaria-infected red blood cells stick onto non-infected cells, forming flower-shaped ‘rosettes’. These rosettes camouflage the parasites as they hide away from circulating immune cells. 

Mosquirix contains a protein fragment from P. falciparum, alongside another derived from the hepatitis B virus, a unique combo designed to provoke a stronger immune response. If an infected mosquito bites a vaccinated individual, the parasite’s entry into the liver (the organ where it matures and divides) will be blocked.

The WHO is basing their decision on data collected in previous clinical trials, the largest of which involved over 800,000 children across three African countries. These studies found Mosquirix to be safe and helped protect children in regions with moderate to high malarial rates.

However, the efficacy of protection has raised doubts among some experts. The vaccine only lowered the rate of hospitalization from malaria by around 30 percent. Additionally, the entire course of treatment requires four injections over 18 months, starting when infants are about six months old. In addition, despite discounts offered by the manufacturer, GlaxoSmithKline, a cost of $5 per shot may be prohibitive to families in the region. 

Still, this marks the end of a 100-year hunt for a malarial vaccine. With a carefully considered rollout plan, Mosquirix has the potential to save thousands of lives in malaria-affected geographies.