Malawi on Thursday launched Africa's first drone-testing corridor as developing countries explore how drones could be used during humanitarian crises such as floods, or to deliver blood for HIV tests.

The project, which will cover up to 40 kilometres (25 miles) around the administrative capital Lilongwe, will be fully operational by April in a collaboration between Malawi and UNICEF.

"Our primary purpose is to help children. (Drone) technology has many potential applications," Johannes Wedenig, a UNICEF official, told state officials at the launch in Lilongwe.

UNICEF estimates that in Malawi it can take 11 days to get HIV blood samples to a laboratory -- often using motorbikes or ambulances -- and up to four weeks for the results to be delivered back.

Drones "can cut the time it takes to get an HIV test result... it is essential to get that child onto treatment as soon as possible," Wedenig said.

Nearly 40,000 children in Malawi are born to HIV-positive mothers each year, according to UNICEF, with the country suffering an HIV prevalence rate of 10 percent, one of the highest in the world.

Drones will be tested at the site for their capacity to collect imagery, boost communication and carry low-weight items such as emergency medical supplies, vaccines and samples.

The maximum test altitude will be 500 metres.

"Malawi has over the past years faced serious droughts and flooding," Minister of Transport and Public Works Jappie Mhango said.

"The launch of the testing corridor is particularly important to support transportation and data collection where land transport infrastructure is either not feasible or difficult during emergencies."

In October, Rwanda inaugurated a drone operation to experiment with supplying medical care to rural parts of Africa.