Infectivity of adult and pediatric COVID-19 patients

Abstract

Objective: we aimed to describe the infectivity of adult and pediatric COVID-19 patients in the presence of viral shedding and anti-SARS-CoV-2 antibody response. Materials and methods: a total of 408 consequent samples from eleven adults and five pediatric patients with SARS-CoV-2 infection were included. Reverse transcription-polymerase chain reaction (RT-PCR) and viral culture were performed for the samples obtained every other day from saliva, nasopharynx, feces, serum, urine, and tear. Anti-SARS-CoV-2 antibodies were measured. Results: 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 symptom onset to admission was three days. The viral RNA was positive in 44.7 % of the nasopharynx and 37.6% of saliva samples up to 16 days in adults and 19 days in children. We detected the latest viral culture positivity in the nasopharynx on day eight of symptoms. The viral RNA was found in 6.1% of feces, 4.4% of serum, 4.3 % of tear, 2.9% of urine. The earliest seroconversion was the seventh day for adults and the eighth day for children. On the 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. Conclusion: the infectivity of a positive patient is low after eight days of symptoms. The risk of fecal-oral transmission is very low, and strict hand hygiene measures could be preventive.