A STAGGERING 86 per cent of people who tested positive for the coronavirus during lockdown did not have key symptoms, doctors have warned.
The NHS states that a new persistent cough, a high temperature or a loss of taste and smell are the key symptoms to look out for.
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Researchers at University College London (UCL) have now claimed that a more widespread testing programme is needed to catch cases where symptoms are not always visible or obvious.
This they say will help reduce further outbreaks.
Experts used data from the Office for National Statistics (ONS) which is based on a large population survey looking at Covid-19 symptoms and Covid test results.
The Infection Survey pilot from the ONS included data from 36,061 people living in England, Wales and Northern Ireland.
The study, published in Clinical Epidemiology looked specifically at these patients who tested between April 26 and June 27 this year and whether or not they had any symptoms.
The experts have now revealed that 115 people (0.32 per cent) had a positive test result.
Looking at participants with the top three Covid symptoms highlighted by the NHS and just 158 (0.43 per cent) experienced these on the day they were tested.
Of the 115 patients that tested positive, 16 (13.9 per cent) reported symptoms in contrast to 99 (86.1 per cent), who did not report any symptoms on the day they were tested.
Experts have previously urged the government to list other symptoms as official warning signs and the study also included data on people who reported symptoms such as fatigue and shortness of breath.
Of those who tested positive for the virus, 25 (23,5 per cent) were symptomatic while 88 (76.5 per cent) were asymptomatic on the day of testing.
Professor Irene Petersen (UCL Epidemiology & Health Care) said the fact that so many people who tested positive were asymptomatic on the day of testing “calls for a change to future testing strategies”.
She continued: “More widespread testing will help to capture “silent” transmission and potentially prevent future outbreaks.
“Future testing programmes should involve frequent testing of a wider group of individuals, not just symptomatic cases, especially in high-risk settings or places where many people work or live close together such as meat factories or university halls. In the case of university halls, it may be particularly relevant to test all students before they go home for Christmas.
“Pooled testing could be one way to help implement a widespread testing strategy where several tests are pooled together in one analysis to save time and resources on individual testing.
“This strategy would be an efficient way to test when the overall prevalence is low as negative pooled samples can quickly show a large group of people are not infectious.”
As part of the report, the authors also noted various other studies that show that a low proportion of those testing positive for the virus are asymptomatic.
They added that this varies from case to case.
They reference a case in Bejing where of 262 confirmed cases admitted to hospitals, just three (5 per cent) were asymptomatic.
It also looked at reports from Italy that suggest between 40 to 75 per cent of people were asymptomatic.
Other studies conducted in Iceland, found that of 13,000 residents, 43 out of 100 with a positive test were asymptomatic.