Lengthening peak loads from from Covid variants may influence best times for testing

Evolving peak SARS-CoV-2 loads relative to symptom onset may influence home-test timing Median SARS-CoV-2 viral loads, as measured by polymerase chain reaction cycle threshold and antigen concentrations, rose from symptom onset, peaking on the fourth or fifth day of symptoms. CIDRAP

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The authors of the study, published today in Clinical Infectious Diseases, say the findings have implications for the use of rapid antigen tests for COVID-19 and flu.

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