Thousands of nurses, doctors and healthcare workers could be carrying Covid-19 without realising they've been infected according to a new study from researchers at Cambridge University.
The team say that these people may, in many cases, show no symptoms at all.
The Cambridge team pro-actively swabbed and tested over 1200 NHS staff at Addenbrooke’s Hospital across April.
Of the more than 1000 staff members reporting fit for duty during the study period, 3% tested positive for the Covid-19 virus. On closer questioning, about half of them admitted to vague symptoms that they had dismissed as inconsequential, and a quarter confirmed remaining symptom-free throughout.
Researchers then looked at where the virus was more prevalent among staff and found that despite wearing the proper protective equipment, staff working in so-called "red areas" where Covid-19 patients are treated, were three times more likely to test positive for the virus.
Researchers said it was not clear whether this genuinely reflects greater rates of transmission from patients to staff in red areas. Staff may have instead transmitted the virus to each other or acquired it at home. And staff working in the “red” areas were also swabbed earlier in the study, closerto when the lockdown was first initiated, so the higher rates of infection in this group might just be a symptom of higher rates of virus circulating in the community at the time.
Extrapolating these results, the researchers suggested that as many as 15,000 staff could have been infected in hospitals during April.
The team at Cambridge University are calling for more testing for staff in the NHS.
Mike Weekes, the report's author, said: "“All staff need to get tested regularly for COVID19, regardless of whether they have any sort of symptoms – this will be vital to stop infection spreading within the hospital setting.”
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