There is no evidence to suggest people who have recovered from coronavirus then have immunity, according to the World Health Organisation.
Senior epidemiologists at the WHO have warned that there is no proof those who have been infected cannot be infected again, despite the hopes governments across the world have put on antibody tests.
The British Government has bought 3.5 million serology tests, which measure levels of antibodies in blood plasma, even though they are not definitive of growing levels of herd immunity.
Many tests being developed are pin prick blood tests similar to widely used instant HIV tests and measure for raised levels of the antibodies the body uses to fight the virus.
READ MORE: Coronavirus vaccine trials could be finished by mid-August, says expert
Speaking at a press conference in Geneva, Dr Maria van Kerkhove said: “There are a lot of countries that are suggesting using rapid diagnostic serological tests to be able to capture what they think will be a measure of immunity.
“Right now, we have no evidence that the use of a serological test can show that an individual has immunity or is protected from reinfection.”
She added: “These antibody tests will be able to measure that level of seroprevalence – that level of antibodies but that does not mean that somebody with antibodies means that they are immune.”
Dr van Kerkhove said it was “a good thing” that so many tests are being developed.
But she cautioned: “We need to ensure that they are validated so that we know what they say they attempt to measure they are actually measuring.”
Her colleague Dr Michael Ryan said the antibody tests also raised ethical questions.
“There are serious ethical issues around the use of such an approach and we need to address it very carefully, we also need to look at the length of protection that antibodies might give,” he said.
READ MORE: Fidelma Cook: There will come reckoning for British politicians over coronavirus
“You might have someone who believes they are seropositive (have been infected) and protected in a situation where they may be exposed and in fact they are susceptible to the disease.”
Dr Ryan said the tests had to be used as part of a coherent public health policy.
The WHO is due to issue updated guidance on the issue this weekend.
_____________________________________________
News from trusted and credible sources is essential at all times, but especially now as the coronavirus pandemic impacts on all aspects of our lives. To make sure you stay informed during this difficult time our coverage of the crisis is free.
However, producing The Herald's unrivalled analysis, insight and opinion on a daily basis still costs money and, as our traditional revenue streams collapse, we need your support to sustain our quality journalism.
To help us get through this, we’re asking readers to take a digital subscription to The Herald. You can sign up now for just £2 for two months.
If you choose to sign up, we’ll offer a faster loading, advert-light experience – and deliver a digital version of the print product to your device every day.
Thank you, and stay safe.
Why are you making commenting on The Herald only available to subscribers?
It should have been a safe space for informed debate, somewhere for readers to discuss issues around the biggest stories of the day, but all too often the below the line comments on most websites have become bogged down by off-topic discussions and abuse.
heraldscotland.com is tackling this problem by allowing only subscribers to comment.
We are doing this to improve the experience for our loyal readers and we believe it will reduce the ability of trolls and troublemakers, who occasionally find their way onto our site, to abuse our journalists and readers. We also hope it will help the comments section fulfil its promise as a part of Scotland's conversation with itself.
We are lucky at The Herald. We are read by an informed, educated readership who can add their knowledge and insights to our stories.
That is invaluable.
We are making the subscriber-only change to support our valued readers, who tell us they don't want the site cluttered up with irrelevant comments, untruths and abuse.
In the past, the journalist’s job was to collect and distribute information to the audience. Technology means that readers can shape a discussion. We look forward to hearing from you on heraldscotland.com
Comments & Moderation
Readers’ comments: You are personally liable for the content of any comments you upload to this website, so please act responsibly. We do not pre-moderate or monitor readers’ comments appearing on our websites, but we do post-moderate in response to complaints we receive or otherwise when a potential problem comes to our attention. You can make a complaint by using the ‘report this post’ link . We may then apply our discretion under the user terms to amend or delete comments.
Post moderation is undertaken full-time 9am-6pm on weekdays, and on a part-time basis outwith those hours.
Read the rules hereLast Updated:
Report this comment Cancel