Scientists advising the World Health Organization have recommended the use of the Oxford/Astrazeneca vaccine in all adults.
The WHO’s Strategic Advisory Group of Experts on Immunisation has issued interim recommendations on the vaccine, saying the COVID-19 jab could be given to people aged 18 and above “without an upper age limit”.
Dr Alejandro Cravioto, chairman of the advisory group, told a press briefing: “That means people over the age of 65 years of age should be given the vaccination.”
It comes after a number of countries in the EU have opted not to give the jab to those over the age of 65, including Spain, Germany, France, Italy, Austria and Norway.
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Dr Cravioto said the vaccine should be administered in two doses between eight and 12 weeks apart, which is also the recommendation of UK regulators.
Dr Michael Head, senior research fellow in global health, University of Southampton, said: "It is good to see the WHO recommend the use of the Oxford/AstraZeneca vaccine in all age groups, including older populations.
“It is also interesting to see they recommend the longer gap between first and second dose, which reinforces the UK vaccine rollout approach and the recommendations of the JCVI [Joint Committee on Vaccination and Immunisation].”
Spain approved the vaccine for use in people aged 18 to 55 on Friday, becoming the latest country to limit the shot to younger people due to a lack of data on its use among the elderly.
Italy also recommends preferential use for adults of 55 and under, while Germany, France, Austria and Norway will only administer the shot to people younger than 65.
The European Medicines Agency has approved the vaccine for all adults but said there was not yet enough results for people over the age of 55 to determine how well it worked in that group.
South Africa has paused the rollout of the vaccine following data in a small clinical trial that showed it gave minimal protection against mild to moderate illness from the 501Y.V2 variant of the virus now dominant in the country.
Prior to the widespread circulation of the more contagious variant, the vaccine was showing efficacy of around 75%, researchers said.
In a later analysis based mostly on infections by the new variant, there was only a 22% lower risk of developing mild-to-moderate COVID-19 versus those given a placebo.
Although researchers said the figure was not statistically significant, due to trial design, it is well below the benchmark of at least 50% regulators have set for vaccines to be considered effective against the virus.
AstraZeneca said on Saturday it believes its vaccine could protect against severe disease and that it has already started adapting it against the 501Y.V2 variant.
Prof Sarah Gilbert, chief investigator on the Oxford vaccine trial, added “It is excellent news that the WHO has recommended use of the SARS CoV-2 vaccine first produced in Oxford.
"This decision paves the way to more widespread use of the vaccine to protect people against COVID-19 and gain control of the pandemic.”
Meanwhile, the WHO and Unicef have said that after countries have vaccinated their health and care workforce and their highest at-risk groups they should share their vaccines.
This would mean that other countries can do the same, they said.
Almost 130 countries – with a combined population of 2.5 billion people – are yet to deliver a single vaccine to their citizens.
Of the 128 million jabs delivered so far, three-quarters have taken place in just 10 countries.
The WHO and Unicef have also called for vaccine manufacturers to allocate the limited vaccine supply “equitably”.
Around the world, more than 107 million cases of COVID-19 have been recorded and it has caused more than 2.3 million deaths.
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