NHS staff should have regular tests for Covid-19, scientists have said, after a new study highlighted the proportion of staff who had the disease but showed no symptoms.
The new study found that one in six maternity health workers have had Covid-19.
And one in three of these were completely asymptomatic – meaning they continued to go about their work as usual, potentially passing the virus on to mothers and their new babies.
The new study, published in the journal Anaesthesia, examined infection rates among workers in two London hospital maternity units.
In total, 200 anaesthetists, midwives and obstetricians from University College London Hospital and St George’s Hospital, with no previously confirmed diagnosis of Covid-19, were given antibody tests – which show whether or not a person has previously been infected.
Of these, 29 were found to have previously been infected.
Only six of these had a fever and 10 recalled having a cough.
Fifteen of them suffered anosmia – a loss of sense of taste or smell.
And 10 of them had no symptoms whatsoever.
Among all of those who were found to have previously been infected, 59% had not self-isolated at any point and had continued to provide care to patients.
The authors wrote: “This has significant implications for the risk of occupational transmission of SARS-CoV-2 for both staff and patients in maternity units. Regular testing of staff, including asymptomatic staff, should be considered to reduce transmission risk.”
They added: “Until we have robust evidence as to the risk posed by asymptomatic infected individuals to others, and as to the risk of Covid-19 to babies, particularly during pregnancy, our study suggests that extreme caution is advisable in maternity settings, particularly the consistent use of effective personal protective equipment and other known effective measures including social distancing of staff and the regular washing of hands.
“We also recommend that all obstetric healthcare institutions should consider regular serology testing for staff, as well as the immediate isolation of any staff who lose their sense of taste and smell, even in the absence of cough or fever.
“Regular testing and consistent use of PPE are likely to be the cornerstones of pandemic control.”
A Department of Health and Social Care spokeswoman said: “We have significantly ramped up our testing capacity, meaning NHS Trusts can now routinely and strategically test asymptomatic frontline staff in appropriate circumstances.
“At every stage we have been guided by the latest scientific evidence and we are following advice from Sage on the appropriate frequency of repeat testing.”