New research from the University of East Anglia in Norfolk suggests a large proportion of NHS workers may have already had coronavirus with mild symptoms. The study found almost two thirds of staff at one London trust lost their sense of smell or taste in April, before it was formally added to the list of Covid-19 symptoms in the UK on May 18th.
Researchers found a strong association between smell loss and positive Covid-19 test results, with those who had lost their sense of smell being five times more likely to test positive.
This suggests that a large proportion of healthcare workers may have already been infected with Covid-19, with only mild symptoms. We conducted this research at Barts Health, however we would expect to see similar results from other NHS trusts too.
The study, in collaboration with University College London, found that 168 out of the 262 healthcare workers (64.1%) who completed the questionnaire reported losing their sense of smell or taste at some point between mid-February and mid-April.
Just 73 of the 262 participants had been tested for Covid-19 at the time, with 56 of these confirmed positive.
Cases like this most likely went undiagnosed at the time because of a lack of awareness about smell loss as a symptom. This is really important because healthcare professionals are at the front line of the pandemic and are at high risk of both contracting and spreading coronavirus.
The survey has also been running in two hospitals in Norfolk with the results due to be published soon.