Testing hampered by swab sticks too long for bottles
HOME testing kits sent to households throughout the country have swab sticks that are too long for the sample bottle they go inside, The Daily Telegraph can reveal.
The issue may explain why the volunteers at testing centres have reported that many samples are being returned without “the lids screwed on properly”, which has contributed to delays in patients receiving results and reduced the number of tests processed each day.
The Government is sending tens of thousands of DIY Covid-19 test kits to households in an effort to better understand the spread of coronavirus across the country.
The swab sticks are designed with a weak point in the middle that should allow them to be broken in half after use, with the end containing the cotton wool sample supposed to then fit neatly into the bottle.
However, it appears that some swab sticks have the breakpoint at the wrong spot, which means that the sample end is too long to fit easily in its container and must be forced into the bottle, or the lid left partially open, risking crosscontamination.
“It was a huge challenge to then get the lid of the tube on. It took me about five minutes,” said Catherine, 55, who is taking part in the Office for National Statistics survey.
Her son Tom, 22, said: “I had to use all of my strength to shut the cap. It seems like a design flaw.”
He added: “When you break it the swab ends up about two or three millimetres too long to fit easily back in the tube.
“So I really wasn’t surprised to hear radio reports yesterday that labs are being sent back tests without the cap on.
“If my grandma got sent one of these tests, I’m really not sure how she’d be able to close the lid properly,” he added.
Prof Alan Mcnally, the infectious disease lead at the Milton Keynes Lighthouse Lab for Covid-19, said on Wednesday that while the vast majority of samples were processed quickly, “hiccups” were delaying a substantial minority.
“One of the things that really hold us up is when people haven’t applied the barcodes properly to the sample tubes,” he told BBC Radio Four.
“We also get samples where the lid hasn’t been screwed on properly.
“This means the sample leaks out and we have to try to recover it so we can test it. There will be occasions where it takes longer to test, and usually it’s because of small hiccups like that.”
Nicola Stonehouse, a professor in molecular virology at the University of Leeds, said that a lack of a standardised testing kit also contributed to delays – and likely explained why issues around swab tests lengths are not universal, with some users reporting no problems.
“There’s a lot of variety in the sample tubes that are coming in,” she told The Telegraph. “This means that more human intervention is required to process them, slowing things down.
“A couple of weeks ago about 20 to 30 per cent of tests arriving at labs needed some form of human intervention – be it because a barcode was incorrectly applied, the lid had come off or the PCR test needed adjusting to fit the size of the test tube.”
Adrian Walker, a lead biomedical engineer at Mologic, which has been manufacturing diagnostics tests for Covid-19 since April, said that there were likely to be large variations between the swabs produced by different manufacturers as organisations decided their own approach based on resources available.
The tubes provided are thought to be supplied by a separate manufacturer.
A Department of Health and Social Care spokesman said: “More than two million people have now been tested in the UK and the vast majority report no issues with the testing process.”