Families sharing dwindling supplies of Covid rapid home test kits amid Omicron’s push are being warned of unreliable results.
Sticking swabs into multiple noses before placing samples on test cards could produce false-negative results by diluting a virus sample, said Susan Butler-Wu, a clinical microbiologist at the University of California’s Keck School of Medicine. from South. Atlantic.
The warnings come as families are said to be using a single kit to test multiple people before heading to group events. A positive result would allow families to know that at least one person has Covid, failing to be able to determine the exact person infected.
The problem is, Ms Butler-Wu told writer Rachel Gutman, that false negatives can occur when too many human cells from more than one nose can dilute an infected person’s positive sample.
It can also spread Covid to someone who may not have had the virus to begin with and could otherwise have avoided contracting it within the family.
Jennifer Nuzzo, senior researcher at the Johns Hopkins Center for Health Security, told the outlet that batch testing in groups of up to 10, using their own swabs, works with PCR testing.
But rapid test kits are designed to test a single sample from a single swab, and there is no data to determine the actual reliability of results when pulled from off-label “pooled” testing.
A study by E25 Bio attempted to answer this question and found that its rapid test kit could detect one positive and symptomatic sample among 19 negative samples.
Bobby Brooke Herrera, chief scientific officer of E25Bio, told the outlet that families shouldn’t “go rogue” and stick multiple swabs in a bottle with a buffer solution measured for just one.
“By the time you put the fourth swab in the swab, you’ll probably be out of swab,” he said.
Read the full article, Families go rogue with rapid tests, at Atlantic.
The Independent Gt