Infectivity of Adult and Pediatric COVID-19 Patients

We report infectivity of adult and pediatric COVID-19 patients in presence of viral shedding and anti-SARS-CoV-2 antibody response A total of 408 consequent samples from eleven adult and five pediatric patients with SARS-CoV-2 infection were included. The samples every second day from saliva, nasopharynx, feces, serum, urine, tear were studied by RT-PCR and viral culture. Anti-SARS-CoV-2 antibodies were measured. The median duration of RNA shedding in all specimens was 7(2-15) days in adults and 5(3-19) days in children. The median duration from onset of symptoms to admission was three days.The viral RNA was positive in 44.7 % of the nasopharynx and 37.6% of saliva samples up 16 days in adults and 19 days in chldren. The latest viral culture positivity was detected on day 8 of symptoms in nasopharynx. The viral RNA was found in 6.1% of feces, 4.4% ofserum, 4.3 % of tear, 2.9% of urine. The earliest seroconversion was the 7th day for adults and 8th day for children. Atthe 14th day, total antibody positivity was 78% in adults, and 80% in children. After seroconversion, the viral RNA was still detected in the nasopharynx and saliva of three patients, however, the infectious virus was not present. Earlier hospital admission could be associated with shorter SARS-CoV-2 RNA shedding. The infectivity of patient is very low after 8 days of symptoms. The risk of fecal-oral transmission is very low, and strict hand hygiene measures could be preventive. The positive antibody test result could be used as a discharge criterion.