Hundreds of children under the age of five are to be vaccinated in western Kenya, as the health ministry rolls out its programme to five counties there.

The “RTS,S” vaccine was first introduced in 2019 in eight counties that have a high malaria burden, helping to bring down the number of children being hospitalised for malaria or dying of it.

To date, more than 1.3 million African children have received at least 1 of the 4 doses of the vaccine since it was piloted four years age. The first dose is given from the age six months, and the fourth dose at two years.

“RTS,S” is the only approved malaria vaccine. It took scientists more than 30 years to develop and it is effective in about 30% of cases.

The mosquito-borne illness kills more than 400,000 people each year, most of them children in sub-Saharan Africa.

Ghana and Malawi have also expanded access to the vaccine in areas that have high numbers of malaria cases.

The World Health Organization says that the vaccine should be rolled out across all of sub-Saharan Africa, but the manufacturer, GlaxoSmithKline, says it can only produce about 15 million doses annually.