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'A One-Off Test Is A Folly': The Truth Behind Covid False Negative Covid Results
When Sarah found herself suffering sudden bouts of breathlessness in May, she took herself to hospital.
But after her Covid-19 swab test came back negative, doctors said she was probably anxious, and sent her home.
Despite this, Sarah’s symptoms continued to worsen. A week later, she was rushed to hospital in an ambulance. Paramedics told her that based on her clinic observations, she should be in a coma.
Then came more surprising news: She had tested positive for coronavirus.
A doctor explained her first test had been a false negative – a result that comes up despite the patient having the virus, and possibly being contagious.
As a clinically vulnerable Covid-19 patient with a chronic illness, I have had frequent contact with hospitals and healthcare systems during this pandemic. I have also been told by doctors that the potential for false negative results is high, so I decided to find out if this was true.
The answer, according to the experts I spoke to for this article, is a resounding yes.
Sarah’s story – given to a patient safety charity under a pseudonym – is one that resonates with Dr Claudia Paoloni.
Paoloni, president of the Hospital Consultants and Specialists Association, detailed another case in which a patient tested negative twice: once when she was first admitted to hospital and once later in her hospital stay. She finally tested positive on her third test – by which time she was on a ventilator in intensive care.
“To use as a one-off test in any capacity to exclude someone from having Covid-19 is a folly.”
Paolini believes Covid-19 swab tests produce a troublingly high rate of false negative results, and the problem lies in the reliance on a single test.
“To use as a one-off test in any capacity to exclude someone from having Covid-19 is a folly.”
If you want to exclude someone from having the virus, Paoloni said, you must do multiple tests and collect multiple negative results.
“If the test and tracing system is not working, which is...
