The potential for IgM cross-reactivity with rheumatoid factor–positive serum samples was observed in blood tests used to detect IgM SARS-CoV-2 by means of gold immunochromatographic and enzyme-linked ...

Polymerase chain reaction (PCR) and rapid (antigen) tests for COVID-19 both involve taking a swab. Results for a PCR test take longer, as it needs to go to a laboratory. It is more costly but tends to ...

People with diabetes have been urged to take extra caution during the COVID-19 pandemic. If you have diabetes, you’ve likely heard that COVID-19 is generally considered to be more dangerous for people ...

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This Journal feature begins with a case vignette highlighting a common clinical problem. Evidence supporting various strategies is then presented, followed by a review of formal guidelines, when they ...

Taking a COVID-19 test at home seems simple enough: If you get a line, you're positive for the coronavirus. But what if your results aren't so obvious? For instance, if you only get a very faint line ...

The COVID-19 pandemic continues to rage, with more than five million deaths worldwide. The urgent, global nature of the pandemic has led to great innovation with novel vaccines and diagnostics, ...

Early research backed by the National Institutes of Health on several popular rapid COVID-19 antigen tests suggest the kits will still work to detect cases of the Omicron variant despite a "reduced ...

Dr. Matt Binnicker, an expert in the diagnosis of infectious diseases, reviews scenarios where an at-home antigen test is a good option, and when to seek out a lab-based PCR. The omicron variant is ...

Rapid antigen tests may be less sensitive at detecting the highly contagious omicron variant and could lead to results that are "false negative," the Food and Drug Administration said Tuesday.