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SARS-CoV-2 Virus Dynamics in Recently Infected People-Data From a Household Transmission Study
Alexandra M Mellis1, Jennifer K Meece2, Natasha B Halasa3
1Centers for Disease Control and Prevention, Atlanta, Georgia, USA.
Abstract:
We used daily real-time reverse-transcription polymerase chain reaction (RT-PCR) results from 67 cases of SARS-CoV-2 infection in a household transmission study, conducted April 2020-May 2021, to examine the trajectory of cycle threshold (Ct) values, an inverse correlate of viral RNA concentration. Ct values varied across RT-PCR platforms and by participant age. Specimens collected from children and adolescents had higher Ct values and adults aged ≥50 years showed lower Ct values than adults aged 18-49 years. Ct values were lower on days when participants reported experiencing symptoms, with the lowest Ct value occurring 2-6 days after symptom onset.
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