In a study of 303 SARS-CoV-2 patients (89 of whom were persistently symptom-free), symptomatic and asymptomatic infected individuals had similar Ct values in PCR during the course, i.e. they released comparable amounts of viral RNA.1 In another study published on behalf of the British Geriatric Society, the authors concluded that systematic prevalence testing is needed, particularly in the nursing home sector, to reduce the risk of transmission by asymptomatic carriers and to manage outbreaks in this setting. 2Asymptomatic
SARS-CoV-2 virus carriers have a similar viral load to symptomatic patients. Isolation of infectious people must therefore be carried out regardless of signs of illness. Screening is used to ensure this or to come a step closer to this goal, which has not seemed feasible so far due to the insufficient area-wide capacity of PCR testing.
1. Lee S, Kim T, Lee E, et al. Clinical Course and Molecular Viral Shedding Among Asymptomatic and Symptomatic Patients With SARS-CoV-2 Infection in a Community Treatment Center in the Republic of Korea. JAMA Intern Med. Published online August 06, 2020. doi:10.1001/jamainternmed.2020.3862
2. Sean P Kennelly, Adam H Dyer, Claire Noonan, Ruth Martin, Siobhan M Kennelly, Alan Martin, Desmond O’Neill, Aoife Fallon, Asymptomatic carriage rates and case-fatality of SARS-CoV-2 infection in residents and staff in Irish nursing homes, Age and Ageing, , afaa220,