Some Covid-19 infections could be missed by inefficient swabbing

Some Covid-19 infections could be missed through poor technique when patients are being swabbed for a test, new Irish research suggests*.

With Covid-19 putting health systems under huge pressure, and public health measures to control the virus heavily reliant on testing, a team of researchers at Beaumont Hospital in Dublin decided to test the quality of swabbing, which is used to collect samples for analysis in the laboratory.

This is the first time the quality of nasopharyngeal swabbing technique has been tested in this way, they believe.

The study comes as the National Public Health Emergency Team (Nphet) announced three additional deaths from Covid-19, bringing the total to 1,830. There were also 811 confirmed cases of the virus announced on Tuesday evening.

More than 1.3 million people in Ireland have so far been tested for Covid-19, starting with a sample taken by a swab inserted inside the back of the throat and nose. The sample is then placed in a fluid and transported to a laboratory for processing using a technique known as PCR (Polymerase Chain Reaction), which looks for DNA fragments of the virus.

PCR is regarded as the “gold standard” of Covid-19 testing but is reliant on swabbing being carried out efficiently to pick up sputum from inside the patient’s nose and throat.