File picture: Sang Tan/AP

Johannesburg - In a historic first, Malawi plans to roll out a malaria vaccine pilot programme for children on Tuesday.

The mosquito-borne disease kills hundreds of thousands of people a year, the vast majority of them in Africa.

"Malaria is still a tragically deadly disease. There are over 250,000 deaths of children in Africa every year because of malaria," Mary Hamel, World Health Organization coordinator for the Malaria Vaccine Implementation Programme, told dpa.

"It's intolerable, the devastating effect for the families, societies," she added. "It's the potential to save so many children's lives that makes this vaccine so exciting."

Malawi is one of three African nations, including Ghana and Kenya, that have been chosen to pilot the new vaccine, which took some 30 years to develop.

The WHO-coordinated Malaria Vaccine Implementation Programme is a collaborative effort with the ministries of health in those three countries.

Named RTS,S, it "is the world's first malaria vaccine that has been shown to provide partial protection against malaria in young children," according to the WHO.

In a clinical trial, children who received doses of the vaccine - developed by GlaxoSmithKline - had a lower chance of developing malaria, the WHO says, as well as of developing severe malaria.

A study showed the vaccine prevented about four in 10 malaria cases among children and "overall, there were 29-per-cent fewer cases of severe malaria in children who received the vaccine."

The vaccine requires four shots for children starting from about age 5 months to 2 years.

The pilot programme - expected to last until the end of 2022 - now aims to reach some 360,000 children per year across the three countries.

Like impregnated mosquito nets, the vaccine isn't a perfect solution, with Hamel noting "there is hope that this vaccine could be improved further."

However, it is hoped it can still bring significant advances, and save tens of thousands of children's lives.

"WHO expects this vaccine could have considerable impact," she said.

These sentiments were echoed by Pedro Alonso, director of WHO's Global Malaria Programme. "The fight against malaria is one where we use imperfect tools; only when we combine them can we achieve great impact. This malaria vaccine adds a tool to our toolkit," he told dpa.

"This vaccine will be rolled out at a time when progress in the global malaria response has stalled," he added, noting that a resurgence of the disease has been seen in some countries that had once achieved great progress.

Financing for the pilot programme is provided by Gavi, the Global Fund to Fight AIDS, Tuberculosis and Malaria, and others.

"This malaria vaccine is a prime example of how public resources and philanthropy can work together with pharma companies to achieve success." he told dpa.

"This is the first time that a malaria vaccine has been recommended for phased introduction in several settings in Africa by WHO's top advisory committees for malaria and immunisation. It is an historical moment."