GREEN BAY, Wis. (NBC 26) — In October, the FDA acknowledged that antigen tests may not detect the Omicron variant of coronavirus in the early days of infection. New research may be showing that the reason Omicron isn't detected early in the nasal passages is that it is growing elsewhere in the body.
New medical research from the University of Hong Kong states that the Omicron variant "infects and multiplies 70 times faster than the Delta variant and original SARS-CoV-2" via the bronchial tubes that carry air from your windpipe to lungs. Shortly after that was published in December, a study from the National Health Laboratory Service in South Africa was published that suggests saliva samples might detect Omicron sooner than nasal swabs because of higher viral levels in saliva. On Twitter, a number of medical experts have shared their experiences with swabbing their own throats against nasal passages.
Symptoms are starting v early w Omicron (for a number of reasons I’ve discussed)— Michael Mina (@michaelmina_lab) December 27, 2021
This means that there is a chance the virus isnt yet growing in the nose when you first test
Virus may start further down. Throat swab + nasal may improve chances a swab picks up virus. https://t.co/NfxHqjKpIo
Well, there it is. Today, with the “wrong” (i.e. cold) symptoms and after a string of negative LFTs, I finally took Twitter advice and swabbed my throat as well as my nose (no mean feat with that diddly stick). If you think you might have COVID, consider adding the throat sample pic.twitter.com/YKihOKh6mE— Prof Jennifer L. Rohn (@JennyRohn) December 27, 2021
However, the FDA is urging people to stick to the instructions that come with their at-home tests to avoid risking injury or a false test result.
"The FDA advises that COVID-19 tests should be used as authorized, including following their instructions for use regarding obtaining the sample for testing. The FDA has noted safety concerns regarding self-collection of throat swabs, as they are more complicated than nasal swabs – and if used incorrectly, can cause harm to the patient. The CDC recommends that throat swabs be collected by a trained healthcare provider," an FDA spokesperson told NBC 26.
Dr. Dan Shirley, the interm Medical Director for infection prevention with UW Health, thinks that new tests may be developed once the data proves that Omicron and variants to come grow more significantly beyond the nasal passages. For now, he stresses that it is important to follow the current testing guidelines.
"Testing is complicated already for anything," Dr. Shirley said. "When you alter from those directions, the problem you could have is either a false negative or a false positive."