Abstract
Severe acute respiratory syndrome coronavirus 2 viral load in the upper respiratory tract peaks around symptom onset and infectious virus persists for 10 days in mild-to-moderate coronavirus disease (n = 324 samples analysed). RT-PCR cycle threshold (Ct) values correlate strongly with cultivable virus. Probability of culturing virus declines to 8% in samples with Ct > 35 and to 6% 10 days after onset; it is similar in asymptomatic and symptomatic persons. Asymptomatic persons represent a source of transmissible virus.
Keywords: COVID-19; SARS-CoV-2; coronavirus; infectiousness; public health policy; respiratory virus.
MeSH terms
- Antibodies, Viral / blood*
- Asymptomatic Infections
- Betacoronavirus
- COVID-19
- COVID-19 Testing
- Clinical Laboratory Techniques
- Coronavirus / genetics*
- Coronavirus / isolation & purification
- Coronavirus / pathogenicity*
- Coronavirus Infections / diagnosis*
- Coronavirus Infections / epidemiology
- Coronavirus Infections / virology
- England / epidemiology
- Humans
- Pandemics*
- Pneumonia, Viral / diagnosis*
- Pneumonia, Viral / epidemiology
- Pneumonia, Viral / virology
- RNA, Viral / genetics*
- Reverse Transcriptase Polymerase Chain Reaction
- SARS-CoV-2
- Serologic Tests
- Viral Load
- Virus Shedding / genetics
- Virus Shedding / physiology*
Substances
- Antibodies, Viral
- RNA, Viral