The United Nations heralded Wednesday the forthcoming scale-up of malaria vaccination across Africa after the first shipment of doses arrived in Cameroon.

Since 2019, more than two million children have been jabbed in Ghana, Kenya and Malawi in a pilot phase, resulting in substantial reductions in severe malaria illness and hospitalisations.

Now the scheme is moving into a broader rollout, with 331,200 doses of RTS,S -- the first malaria vaccine recommended by the UN's World Health Organization -- landing Tuesday in Cameroon's capital Yaounde.

The delivery "signals that scale-up of vaccination against malaria across the highest-risk areas on the African continent will begin shortly," the WHO, the UN children's agency UNICEF and the Gavi vaccine alliance said in a joint statement.

They called it "a historic step towards broader vaccination against one of the deadliest diseases for African children".

The doses are donated by manufacturer GSK.

"We encourage all parents to take advantage of this life-saving intervention," said Cameroon's Health Minister Malachie Manaouda, adding that malaria "remains a major public health threat in the country".

A further 1.7 million doses are set for delivery to Burkina Faso, Liberia, Niger and Sierra Leone in the coming weeks.

Malaria is the leading cause of mortality in infants and children aged under five in Liberia, the country's Health Minister Wilhelmina Jallah said.

"This vaccine has the potential to save many lives and reduce the burden of this disease," she added.