Nearly three-quarters of people infected with coronavirus show no symptoms on the day they are tested for the disease, government data has revealed.
Only 28 percent of people who tested positive for the disease in a random sample admitted to having symptoms.
The remaining 72% were completely unaware they carried the coronavirus, having reported no symptoms – which include a fever, cough, or loss of taste and smell.
The findings, released today by the Bureau of National Statistics, shed light on the severity of the asymptomatic spread of the disease – people who transmit the disease unknowingly because they have no idea they are infected .
Several studies have shown that asymptomatic transmission accounts for up to 80% of the spread of Covid-19. The new data is one of the largest studies, involving around 50,000 people.
The results suggest the 1,000 cases of Covid-19 officially diagnosed each day in Britain are only a fraction of the actual number of infections, and the actual tally is at least three times as high – in line with others estimates.
The findings also reinforce the importance of contact tracing, which aims to quickly quarantine anyone who has come into contact with a confirmed case before they have a chance to spread the disease.
Other data from the ONS today revealed that Asians are up to five times more likely to catch the coronavirus than whites.
Only 28 percent of people who tested positive for the disease in a random sample admitted to having symptoms. The remaining 72% were completely unaware they carried the coronavirus (pictured)
Participants in the ONS investigation into coronavirus infections were tested with antigen tests, which can only tell a person if they are currently infected with the virus.
Over the course of the study, over 195,000 swab tests were performed in a representative sample of the general UK population.
Current data is based on swab testing conducted over an eight-week period between June 8 and August 2 and does not cover nursing homes or hospitals.
Symptoms respondents were asked to report were fever, cough, and loss of taste or smell – the three “telltale” signs of the virus.
They were also asked to report shortness of breath, headache, nausea or vomiting, abdominal pain, diarrhea, muscle pain, fatigue, or a sore throat.
Less than a third (28%) of people who tested positive for the virus reported having any of the symptoms, the ONS said.
ASIANS FIVE TIMES MORE LIKELY TO CATCH COVID-19
Asians are up to five times more likely to catch the coronavirus than whites, according to data from a government-run surveillance program.
An Office for National Statistics (ONS) report released today found that seven of 1,510 Britons identified as Asians positive for Covid-19 – a rate of around 0.46%.
For comparison, the rate was 0.12% for whites. The ONS concluded that the risk was slightly higher than the percentage difference and that Asians were 4.8 times more likely to test positive.
No cases were diagnosed in any other ethnic group in England between June 8 and August 2, the date to which the data relate.
But the body claimed black Britons were twice as likely to be diagnosed, based on older numbers.
Antibody test results – which indicate whether a person has ever had the disease – showed a similar gap in ethnicity, with just 4.8% of whites testing positive for the substances. In comparison, the rate was around 10.8% for Asians and 9.5% for black Britons.
Numerous reports have revealed that Blacks, Asians and Ethnic Minorities (BAMEs) in Britain are at a higher risk of dying if they catch coronavirus than whites.
Experts cannot determine exactly why this is the case, but it could be because ethnic minorities are more likely to be poor, use public transport more often, and work in public jobs, which makes them more vulnerable. to interact with strangers and catch the disease.
Epidemiologists have previously told MailOnline that some communities that do not speak English as their mother tongue do not follow social distancing rules as rigorously because public health messages do not reach them.
Professor Paul Hunter, epidemiologist at the University of East Anglia, and Gabriel Scally, professor of public health at the University of Bristol, said there had been a “communication breakdown” and that “the barriers linguistic was certainly a problem ”.
The remainder (72%) had no evidence of symptoms at the time of their swab test or in subsequent tests later.
WE said the results suggested there was a “potentially large number” of asymptomatic cases of the virus.
The report adds that it’s important to note that the symptoms were self-reported rather than professionally diagnosed, so some people may not have noticed they were sick.
Only 165 people in the sample had tested positive, so the team cannot be fully confident in their results as they were working with small numbers.
False positives, people without disease who tested positive in error, could have an effect on the results, the ONS said.
But despite everything, the researchers said the results suggest that at least 64 to 78% of those infected did not show symptoms.
Commenting on the results, Professor James Naismith, Director of the Rosalind Franklin Institute at the University of Oxford, said: “This release is very informative.
“This suggests that about 70% of those infected did not show any symptoms. Although this is good news because for the vast majority Covid-19 is not a serious disease, it is much more difficult to detect its spread.
Kevin McConway, Emeritus Professor of Applied Statistics at the Open University, said: “The data tends to indicate that being infected without having visible symptoms is likely to be common. “
Dr Andrew Preston, reader of microbial pathogenesis at the University of Bath, said today’s data adds to growing body evidence that shows that a “significant proportion of people infected with SARS-CoV2 are asymptomatic ”.
He told MailOnline: “An asymptomatic infection creates a major problem for infection control, people can unknowingly carry the virus.
“Another unknown is the contribution of asymptomatically infected people to the transmission of the virus to other people.
If people without symptoms do not cough, it can be assumed that they expel the virus-laden droplets less.
But Dr Preston said: “Forced exhalation by other means such as singing or screaming appear to be effective mechanisms for spreading infection (eg, high incidence among some choir groups), it doesn It is therefore by no means certain that those who are asymptomatically infected are less able to spread the disease.
“And of course, a person who is asymptomatically infected, even though they transmit less virus, is unlikely to isolate themselves and, therefore, during their infectious period, they could interact with a lot of other people. “
Dr Preston said it was not precisely clear what caused one person to get sick while another showed no signs of illness. But evidence suggests that older people and those with underlying comorbidities are more likely to show symptoms.
ONS data suggests thousands of infected Britons are not tested for Covid-19 because they don’t know they have it.
While anyone can get tested on the NHS, they are unlikely to show up unless they have symptoms that concern them, or a friend, relative or colleague has been diagnosed. which prompts a control.
Government surveillance programs, such as the one run by the ONS with the Department of Health, are the only way to deepen understanding of how many people in the UK have actually been infected.
Separate data released by the ONS indicates that around 3,800 people are infected each day in England alone. Twenty-eight percent of that figure is around 1,000 – which roughly matches the number of cases confirmed each day by the Department of Health.
Various studies have attempted to determine how many cases of Covid-19 are silent, producing extremely high estimates.
Evidence is starting to show that transmission by asymptomatic and presymptomatic patients accounts for between 40% and 80% of Covid-19 cases.
A comprehensive review of 17 studies concluded that more than half of people infected with the coronavirus got it from someone before showing symptoms, called presymptomatic.
It takes an average of six days for a person to develop telltale signs of Covid-19. But in the days leading up to symptoms, patients are contagious and can still pass the deadly virus to others.
Irish academics have said that between 33% and 80% of cases got the virus from people who would not even have known they were even infected.
They warned that presymptomatic transmission alone could cause the virus to spread uncontrollably and “fuel its own epidemic.”
Controlling the spread of the virus between unsuspecting victims is crucial to staying on top of the disease when lockdowns are eased, the team said.
It depends on the success of contact tracing, which involves identifying all people who have been in close contact with a confirmed case.
These people would in theory be isolated, even if they do not have symptoms, so that it is not possible for them to transmit the virus to others at the onset of infection.