The World Health Organization on Monday authorized a second malaria vaccine, a decision that could offer countries a cheaper and more readily available option than the world's first vaccine against parasitic disease.
WHO Director-General Tedros Adhanom Ghebreyesus said the UN health agency was approving the new malaria vaccine based on the advice of two groups of experts, recommending its use in children at risk of contracting the disease.
“As a malaria researcher, I used to dream of the day when we would have a safe and effective vaccine against malaria. Now we have two,” Tedros said.
Oxford University developed the new three-dose vaccine with the help of the Serum Institute of India. Research suggests that it is more than 75% effective and that protection is maintained for at least another year with a booster. Tedros said the vaccine would cost between $2 and $4 and could be available in some countries next year if funders agree to buy it.
Earlier this year, regulatory authorities in Ghana and Burkina Faso approved the vaccine.
"This is one more tool we will have now, but it will not replace mosquito nets or insecticide spraying," said John Johnson of Doctors Without Borders. "This is not the vaccine that will stop malaria."
Johnson was not part of the WHO expert group that gave the green light to the Oxford vaccine.
In 2021, the WHO approved the first malaria vaccine in what it described as a “historic” effort to end the devastating toll the mosquito-borne disease takes on Africa, home to most of the 200 million cases and 400,000 estimated deaths in the world.
But that vaccine, known as Mosquirix and manufactured by GSK, is only 30% effective, requires four doses and the protection wears off in a few months. However, WHO experts said data to date on the vaccines developed by GSK and Oxford do not show which is more effective.
The Bill and Melinda Gates Foundation, one of the largest sponsors of the GSK vaccine, stopped supporting financially to Mosquirix directly in 2015, saying it was less effective than officials would like and that the funds would be better used elsewhere. The foundation said it has continued to help with the vaccine rollout by supporting Gavi, a global vaccine alliance that is purchasing GSK's shots to distribute in poorer countries.
“The big difference with these two vaccines is access,” Johnson said, noting that only a dozen countries will receive limited quantities of the GSK vaccine in the coming years.
GSK has said it can only produce about 15 million doses a year. The Serum Institute has said it could make up to 200 million doses of the Oxford vaccine a year.
Alister Craig, emeritus professor at the Liverpool School of Tropical Medicine, said he would recommend countries trying to get the GSK vaccine to switch to the Oxford vaccine.
If the new vaccine is widely deployed across Africa, it could dramatically reduce the number of serious illnesses and deaths caused by malaria within a few years, Craig said.
None of the malaria vaccines stop transmission, so immunization campaigns alone will not be enough to stop epidemics. Efforts to curb the disease are also being complicated by growing reports of resistance to the main drugs used to treat malaria and the spread of invasive mosquito species .
"It would be foolish to think that this vaccine is going to be the end of the malaria story," Craig said.
In a separate decision, the WHO expert group also authorized the dengue vaccine made by Takeda, which was previously approved by the European Union's drug regulator.
There is no specific treatment for dengue, common in tropical countries in Latin America and Asia. While most infections are mild, severe cases of this mosquito-borne disease can cause internal bleeding, organ damage, and death.
WHO expert groups recommended that Takeda dengue vaccine be used in children aged 6 to 16 years in countries with a high prevalence of the disease.
Previous studies have shown that Takeda's vaccine was about 84% effective in preventing people from being hospitalized with dengue and about 61% effective in stopping symptoms four years after receiving the vaccine.
Nearly 1,000 people have died from dengue this year in an ongoing epidemic in Bangladesh, the worst outbreak of the disease in the country.