The World Health Organization (WHO) has rowed back on guidance after claiming there is “no evidence” those who had been infected with coronavirus were immune from the disease.
In a briefing note published on Sunday morning, the WHO said “there is currently no evidence that people who have recovered from Covid-19 and have antibodies are protected from a second infection”.
But after outcry from the scientific community, the organisation issued a clarification on Sunday - saying that those who had contracted the disease had “some level of protection” from reinfection.
In a statement published on Twitter the WHO said: “Earlier today we tweeted about a new WHO scientific brief on "immunity passports". The thread caused some concern & we would like to clarify.
Earlier today we tweeted about a new WHO scientific brief on "immunity passports". The thread caused some concern & we would like to clarify:— World Health Organization (WHO) (@WHO) April 25, 2020
We expect that most people who are infected with #COVID19 will develop an antibody response that will provide some level of protection. pic.twitter.com/AmxvQQLTjM
“We expect that most people who are infected with #COVID19 will develop an antibody response that will provide some level of protection.
“What we don't yet know is the level of protection or how long it will last.
Latest coronavirus news, updates and advice
“We are working with scientists around the world to better understand the body's response to #COVID19 infection. So far, no studies have answered these important questions.”
The WHO issued the original statement in response to a suggestion from politicians in several countries that so-called “immunity passports” could be issued to people in order to enable them to return to work.
But Professor Babak Javid, the principal investigator at Tsinghua University School of Medicine in Beijing, said the WHO’s statement was “very confusing”.
He said it is “reasonable to assume that they will develop at least short-term immunity from re-infection, the critical questions are how robust that immunity would be, and for how long it would last.”
While Dr Simon Clarke, an associate professor in cellular microbiology at the University of Reading, told The Guardian: “At this stage nobody knows for sure whether this is indeed the case or for how long it will protect someone, it could be weeks, months or years and it would be unwise to make predictions that are not based on any evidence.
“It’s worth remembering that we’ve only known about this disease for about four months, so cannot at this stage have any knowledge about whether immunity lasts beyond this rather limited time frame.