The World Health Organization does not expect global vaccinations against Covid-19 until the middle of next year, a spokeswoman said on Friday.
WHO stressed that the importance of rigorous checks on their effectiveness and safety.
None of the candidate vaccines in advanced clinical trials so far has demonstrated a “clear signal” of efficacy at the level of at least 50% sought by the WHO, spokeswoman Margaret Harris said.
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.
U.S. public health officials and Pfizer said on Thursday a vaccine could be ready for distribution as soon as late October. That would be just ahead of the U.S. election on Nov. 3 in which the pandemic is likely to be a major factor among voters deciding whether President Donald Trump wins a second term.
“We are really not expecting to see widespread vaccination until the middle of next year,” Harris told a U.N. briefing in Geneva.