What is this vaccine?

• The vaccine is called RTS,S aka Mosquirix—and it attacks the most lethal form of malarial parasite called Plasmodium falciparum. 
• It is administered in four doses. The first three are given a month apart—and the final booster shot is given 18 months later.
• It was trialled in three countries in Africa: Ghana, Kenya, and Malawi—where more than 2.3 million doses have been administered, reaching more than 800,000 children. 
• The results showed that it is safe, cheap and can prevent 40% of malaria cases, reduce severe illness in 30% of the cases.

An India angle: Bharat Biotech is expected to be the sole manufacturer of Mosquirix by 2029.

Only 40%? Why is this a big deal?

The problem with malaria: We’ve been looking for a malaria vaccine for a century. And this is the first to be approved for widespread use. The reason for this long wait: The malarial parasite is constantly evolving—and you often have to catch malaria multiple times to even get limited immunity:

“Malaria is caused by a parasite which is far more insidious and sophisticated than the virus that causes Covid. Comparing them is like comparing a person and a cabbage… It has a complicated life cycle across two species (humans and mosquitoes), and even inside our body it morphs between different forms as it infects liver cells and red blood cells.”

The challenge: Any vaccine has to ‘block’ the parasite while it is changing inside you—which is “like nailing jelly to a wall.” Mosquirix targets a particular “sporozoite” form of the parasite—which it takes between the time you are bitten and before it reaches the liver. And that is why it is only 40% effective.

The achievement: To begin with, this is not just the first malaria vaccine, but also the first ever to be developed for a disease caused by parasites—which doctors say is “a huge jump from the science perspective.” More importantly, look at the numbers:

• There are 229 million cases of malaria each year, 409,000 deaths. Of these, 94% are in Africa—where 260,000 children died from the disease in 2019.
• A modeling study estimated that the vaccine can prevent 5.4 million cases of malaria and 23,000 deaths in children younger than 5 each year. That’s not a small achievement.

Most importantly this: The vaccine isn’t a magic bullet, but it is radically more effective when combined with current antimalarial medicines. A study showed that a double-prong approach reduced illness by 62.8%, hospital admission by 70.5%, and deaths by 72.9%. And it is more effective—and surprisingly far easier to distribute—than commonly used measures like insecticide-treated nets, which cut deaths in children under 5 only by about 20%. Think of Mosquirix as a powerful new addition to an arsenal of weapons. 

Big point to note: This is just the first-generation vaccine—and paves the way for others which may be far more effective. For example, the University of Oxford is testing a vaccine—manufactured by India’s Serum Institute—that has proven 77% effective in initial trials. 

What about malaria in India?

Where we are: India has made the biggest strides in reducing the number of malaria cases—which fell from 20 million in 2000 to 5.6 million in 2019. This is the biggest single drop in Southeast Asia. But we still account for 86% of deaths in the region—around 7,700 in 2019. And this: We had actually almost eradicated malaria back in 1950—but lost a lot of ground because of a shortage in DDT. Now our new target for eradication is 2030. 

Point to note: A 2017 World Malaria Report flagged the fact that India has among the poorest systems for malaria surveillance—and likely detects only 8% of its cases.

The vaccine: targets only one form of the malarial parasite: Plasmodium falciparum. It accounts for 99% of all malaria cases in Africa, but only about 50% in Southeast Asia. To deploy the vaccine in India, it would first have to be approved by the government—which typically requires local trials. And it isn’t clear if malaria is a priority for now.

The bottomline: While we fret over a neverending pandemic, it is good to remind ourselves that we have been fighting a far deadlier enemy—and for a longer time. And we may have scored our first significant victory.

Reading list

New York Times and BBC News offer the best overviews. The Print has the Bharat Biotech angle, while Quartz looks at the implications for India. Time magazine has a very good read on why medical breakthroughs alone cannot fight pandemics.