A viral block of text on social media has claimed that if people stop getting tested for Covid-19, it’ll reduce the virus and the likelihood of a second lockdown.
The post reads:
“Can people just stop getting tested ? You do realise You are adding to the problem and taking us into a 2nd phase shutdown? You are giving the GV the numbers of cases and powers to take us into a winter lockdown? Just stop the testing and this will disappear overnight! If you are well enough to get yourself to a testing centre then you're absolutely fine, stay at home for 2 weeks just to be safe, eat well and take your vitamins and then crack on! You don't need to wear a positive covid test like a badge of honour for absolute no reason do you?? You think spring/summer lockers was bad? Wait until its dark more than it is light, no garden to enjoy because its cold and rainy, no festivities to look forward to, no christmas markets or shopping, no taking the kids to see Father Christmas? Plus your standard normal winter illnesses to throw in the mix!! More people will die of suicide than EVER before! Our elderly will die sooner than they should because they will be restricted to their usual things that keep them sane, like community groups? We need social interaction to thrive and stay healthy and i dont need no paid off scientist to do research to tell me that!!! End this now!!!!!”
While there is a lot of opinion in this post, which we can’t fact check, we can look into the claims about how testing works and how testing figures relate to decisions about the lockdown.
Numerous experts disagree with the prediction that a drop or halt in testing would remove the risk of lockdown measures being reinstated.
Professor John Edmunds told Full Fact: “If fewer people were getting tested then it would look like the increase of cases would be slowing down. However, we also look at the level of testing and importantly test positivity (the fraction of tests that are positive) to ascertain what is really going on.”
“Suffice to say it is complicated, but by monitoring testing volumes, test positivity, cases, and uptake of testing in different groups then we can patch together a picture of what is likely to be going on.”
This was echoed by Dr Michael Tildesley who told us: “One thing that this claimant is clearly not aware of is that when scientists make predictions regarding the future course of the epidemic, they take into account the fact that the number of tests carried out has increased.”
“So it is not just the number of positive tests that is important, but the fraction of tests that are positive and how these are dispersed around the country.”
This measurement is known as test positivity. As we mention in our piece on the current state of testing, test positivity is a reflection of how many tests come back positive. If test positivity is low—not many of those getting tested are coming back positive—this could be an indication that the virus is not very prevalent and/or that there is an adequate amount of testing going on (i.e. a low test positivity rate could indicate that not many positive cases are being missed).
However, a low positivity rate could indicate that testing is not reaching the right groups or places.
High test positivity rates can indicate that the virus might be spreading, or that not enough testing is being done. It could also indicate that there is a lot of testing among groups where it is likely to be more prevalent.
Professor Chris Whitty cited rising test positivity in the government’s recent special briefing, as evidence for a rise in positive cases among young people.
The positivity rate isn’t on its own how the scale of the outbreak is measured, but it is one of the measures, alongside the number of tests, which is taken into consideration by experts.
Dr Tildesley also told Full Fact that a reduction in people taking tests, or even testing capacity, may make it harder for the virus to be eradicated: “A major challenge for many neglected diseases is to get testing capacity high enough—agencies often have an incentive to report fewer cases one year than they did they year before and one solution to this is, of course, not to test, because if you don't test you don't find. But this is one of the key reasons why these diseases are extremely hard to eradicate, as they are, in general, so under-reported.”
So even if there was a boycott of testing, the virus would not disappear, it might even make it hang around longer, and there would be numerous factors other than the number of people tested to indicate that the pandemic was still ongoing.