The US and Russia may be trying to introduce mass scale vaccination against Covid-19 in the next couple of months, but the World Health Organisation (WHO) thinks such widespread vaccination is not possible until the middle of next year.
WHO spokeswoman Margaret Harris said none of the candidate vaccines in advanced clinical trials so far has shown a clear signal of efficacy at the level of at least 50%.
“We are really not expecting to see widespread vaccination until the middle of next year,” Harris told a UN briefing in Geneva.
“This phase 3 must take longer because we need to see how truly protective the vaccine is and we also need to see how safe it is,” Harris added.
All data from trials must be shared and compared, she said.
“A lot of people have been vaccinated and what we don’t know is whether the vaccine works...at this stage we do not have the clear signal of whether or not it has the level of worthwhile efficacy and safety...,” she added.
Russia granted regulatory approval to a COVID-19 vaccine in August after less than two months of human testing, prompting some Western experts to question its safety and efficacy.
A report in the Lancet on Friday said that patients involved in early tests of a Russian coronavirus vaccine developed antibodies with “no serious adverse events”. But experts said the trials were too small to prove safety and effectiveness.
Russia announced last month that its vaccine, named “Sputnik V” after the Soviet-era satellite that was the first launched into space in 1957, had already received approval.
This raised concerns among Western scientists over a lack of safety data, with some warning, that moving too quickly on a vaccine could be dangerous.
US President Donald Trump, who will be seeking reelection in November 3 polls, has said a vaccine could be ready for distribution before the elections. The coronavirus pandemic is likely to be a major factor among voters deciding whether President Donald Trump wins a second term.