Last week, the world’s first malaria vaccine was given a green light to be rolled out as part of large-scale implementation projects in three sub-Saharan African countries. With nearly US$ 50 million in funding from the Global Fund to Fight Aids, Tuberculosis and Malaria, Gavi and UNITAID, this initiative marks a critical step in creating new tools for the fight against this devastating disease.
1) Malaria remains a major killer
Despite huge progress in the fight against malaria – the number of cases has halved since 2000 – the mosquito-borne disease remains a major killer. With more than 200 million cases a year, resulting in the deaths of around 1,200 children every day, RTS,S, or Mosquirix to use its brand name, has become one of the most widely anticipated vaccines. Malaria is endemic in almost every country in sub-Saharan Africa (for where the vaccine has been designed), as well as large parts of Asia and Latin America, and demand for a vaccine is likely to be high. Expectations will be even greater. This is the world's first vaccine against a parasite.2) RTS,S is both safe and effective
In clinical trials, RTS,S was found to be both safe and effective. However, it only offered partial protection, with a 39% efficacy at preventing clinical cases of malaria over the course of a four-year follow-up period. Effectiveness was very much dependent upon children receiving all four doses of the vaccine. What’s more, the trials were carried out with the vaccine used in conjunction with high use of other interventions, such as long-lasting insecticide-treated bed nets and anti-malarial drugs.3) Partial protection could go a long way
It is low for a vaccine but given the large number of people at risk, providing protection in just four out of 10 cases could still go a very long way. Ultimately, it’s the public health impact that counts more than the efficacy of the vaccine. Moreover, since there can be more than one episode per child, the trials found that the vaccine prevented on average 1,774 cases of malaria per 1,000 children.4) Pilots will help us get the answers we need
Last year, after RTS,S passed all the required regulatory hurdles, two advisory bodies to the World Health Organization – the Strategic Advisory Group of Experts on immunisation (SAGE) and the Malaria Policy Advisory Committee (MPAC) – recommended against its immediate widespread use. These pilots are being carried out first in order to find out how well the vaccine performs in a real-world setting, to see how feasible it is to get four doses to children – three doses outside of the normal childhood immunisation schedule – and in terms of safety.While we cannot simply roll out the vaccine to everyone, the huge potential to save lives and reduce illness now means we cannot justify holding off indefinitely. These large-scale four-year pilot projects are designed to shed light on how effective the vaccine will be in practice by seeing how it performs in a real-life setting, in high and low transmission areas, with and without high coverage of other interventions. With vaccinations due to begin by 2018, it is hoped that we will soon have the answers we need. Given the vast scale of the number of people who potentially stand to benefit, it is our duty to fill these gaps in our knowledge. And while the testing and hopefully implementation of this vaccine goes on, so does the march of science; scientists are already working to improve upon its effectiveness as well as look towards second generation vaccines.
Credit: World Malaria Report / WHO
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