GENEVA, DPA - The World Health Organisation recommends using the AstraZeneca vaccine against COVID-19 despite recent reports that raised questions about its effectiveness.

    The UN health agency issued its guidance on Wednesday, days after the publication of a study showing that the vaccine offers less protection against the 501Y.V2 variant of the novel coronavirus that was first detected in South Africa.

    The WHO noted that the results of the study only showed limited effectiveness against mild forms of COVID-19 but that there was no evidence that the vaccine does not protect against severe disease.

    Following the advice of an international panel of 26 vaccine experts, the WHO therefore recommended the use of AstraZeneca shots "even if variants are present in a country".

    The WHO's top immunisation specialist, Kate O'Brien, said that all vaccines tend to be less effective against mild forms of disease.

    "There is a plausible expectation that the vaccine will have efficacy against severe disease," she said about the product that was developed by the British-Swedish pharmaceutical giant AstraZeneca and the University of Oxford.

    O'Brien stressed that people who have received any of the available COVID-19 vaccines must keep following pandemic precautions, including physical distance and masks.

    While the shots prevent people from falling ill with COVID-19, there is a risk that they can still transmit the virus to others, she said.

    The WHO said in its recommendation that there is an "urgent need" for global monitoring of new virus variants, which would allow scientists to draw conclusions on vaccines.

    Although there are indications that variants detected in the United Kingdom, South Africa and Brazil are more infectious than earlier ones, global COVID-19 case numbers have been falling for the past four weeks, according to the latest WHO update.

    Numbers fell in all world regions last week.

    The downward trend includes the UK and South Africa, thanks to strict public health measures in both countries, according to the WHO.