Malaria is one of the leading causes of death in children. Now, there is a vaccine.

Every year, malaria kills more than 400,000 people, mostly children. Significant progress has been made in the fight against the disease in recent decades – mortality rates have almost halved – but much remains to be done. A child dies of malaria every two minutes.

Now, for the first time, we could have a vaccine.

The World Health Organization announced Tuesday that Malawi is implementing a pilot program for the first global malaria vaccine. The vaccine, called RTS, S, will be available to all people under 2 years of age. After deployment in Malawi, vaccination will begin in Ghana and Kenya later this year. In total, 360,000 children will receive the vaccine.

In clinical trials, the vaccine has prevented about 40% of malaria cases – and only 30% of the most severe cases. This rate is well below the vaccine success rate for most other childhood diseases: measles vaccine, in comparison, is 97% effective and the varicella vaccine prevents 85% of cases and almost 100% of cases serious.

Nevertheless, it is a huge step forward. Malaria is a mosquito-borne disease that causes fever and chills, as well as severe cases of anemia, convulsions and breathing problems. Even avoiding 40 percent of cases saves many lives, and since part of the life cycle of the malaria parasite takes place inside a human host, the resolution of some cases will benefit even those who do not benefit. immunity.

We have been working for 30 years looking for a malaria vaccine. Although the widespread use of insecticide-treated mosquito nets, preventive treatments and indoor spraying have significantly reduced the number of deaths from malaria, the gains from these approaches have become blurred. last years. Continuing the fight against malaria will require new tools in the toolbox – and this vaccine seems to be extremely promising.

Why a malaria vaccine was such a challenge

Developing a vaccine against malaria – even with moderate efficiency – has been a huge challenge. With many viruses, the virus confers lifetime immunity or at least immunity for many years.

Malaria is not a virus. It is a parasite, and being exposed does not confer immunity for life (although, like the new vaccine, it reduces the risk of contracting malaria again). The parasite is genetically complex compared to a virus, with thousands of potential antigens that researchers have been trying to study.

In addition, according to the Centers for Disease Control and Prevention, malaria vaccination efforts have been hampered by the "lack of a traditional market" – the poorest regions of the world are those hardest hit by malaria. Pharmaceutical companies have therefore little thought of making money. Much of the vaccine research has been funded by philanthropists, WHO and national governments.

This did not prevent all searches. Dozens of potential vaccines for malaria are under development. In 2015, The lancet published the results of a large-scale clinical trial of RTS, S. The vaccine was administered in three doses to infants who received a booster shot at 2 years of age.

The results – 40% of malaria cases averted, including 30% of severe cases and 60% of malaria cases – were a little disappointing at the time for some observers, who had hoped that RTS, S would be even more effective. But they were sufficient to suggest that RTS, S should be scaled up because, as the authors of the study say, "an additional way to fight malaria during the development of the next generation of malaria vaccines" .

Let's hope that the next generation of malaria vaccines will be even better. But in the meantime, RTS, S may be enough to put an end to the recent stagnation of the fight against malaria.

Cases of malaria were decreasing. Then the decline slowed down.

For a long time, we have made impressive progress in the fight against malaria. Historically, malaria has touched the entire world – it was once one of the leading causes of death in the United States, as prevalent here as in Malawi. The eradication efforts in most of the world have been successful, but half of the world's population is still at risk.

The number of deaths from malaria has continued to decline, from more than 800,000 in 2000 to 430,000 in 2015. According to a 2015 study, the decline revealed that 663 million cases of malaria were resolved in Africa between In 2000 and 2015, 68% of cases were prevented through the distribution of insecticide-treated mosquito nets, 19% to artemisinin-based combination therapy and 13% through effect spraying. lingering inside.

Max Roser, our world in data

We continue to use all these tools. But in recent years, public health experts have begun to warn that progress in the fight against malaria could slow down. The WHO found that resistance to artemisinin was becoming more common, with artemisinin-resistant parasites having been detected in five East Asian countries.

Climate change is expanding the number of malaria-carrying mosquitoes, putting at risk populations that had not been exposed previously.

"After more than 15 years of constant progress in the fight against the disease," wrote Bill Gates last week, "the improvement is slowing down. Malaria funding has also increased. If we simply stick to the same tools and strategies, progress will stop and the disease may return. "

That's why it's exciting to hear that a new tool will be available in the fight against malaria. Ten countries expressed interest when WHO solicited partners for the vaccine pilot project and if the program is successful in Malawi, Ghana and Kenya, it will certainly be adopted elsewhere.

"Bed nets and other malaria control measures have made enormous gains over the past 15 years, but progress has stalled or even reversed in some areas. We need new solutions to put malaria control back on track and this vaccine provides us with a promising tool to achieve this, "said WHO Director-General Dr Tedros Adhanom Ghebreyesus in a press release announcing the project. "The malaria vaccine has the potential to save tens of thousands of children."

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