Background:SARS-CoV-2 clinical presentation is associated with the patients’age group.Overall,young indi-viduals present higher proportions of asymptomatic or mild COVID-19 infection,compared to adults.Data on second...Background:SARS-CoV-2 clinical presentation is associated with the patients’age group.Overall,young indi-viduals present higher proportions of asymptomatic or mild COVID-19 infection,compared to adults.Data on secondary COVID-19 transmission in households,according to the cases’age group,are accumulating.Methods:We performed a follow-up cohort study including all COVID-19 real-time polymerase chain reaction(RT-PCR)-confirmed cases(adolescent students and school staff)diagnosed in an epidemiological investigation of a large high school outbreak.We compared the adolescent and adult groups regarding clinical symptoms,time to negative COVID-19 RT-PCR tests,and infection transmission in households.Results:The study population included 817 persons.The confirmed COVID-19 RT-PCR outbreak cases(n=178)were followed(students aged 12-19 years,median age 14 years,n=153,school staffaged 24-67 years,median age 39 years,n=25)and the cases’household close contacts(n=639)were tested.The adolescents had lower symptomatic infection rates,shorter time to negative COVID-19 RT-PCR tests,and lower transmission rates to household members,compared to the adults.The general transmission rate among household contacts was 13.5%,(86/639)ranging from 8.6%in asymptomatic students’contacts to 27.3%in symptomatic staffcontacts.COVID-19 transmission rates were significantly higher in contacts of symptomatic cases compared to asymptomatic cases(odds ratio:2.06,95%CI 1.26-3.4)and higher in adults compared to adolescents(odds ratio:2.69,95%CI 1.43-4.89).Conclusions:Adolescents and adults diagnosed in an outbreak investigation differ as to COVID-19 clinical presen-tation and transmission.As adolescents may show mild or no symptoms,COVID-19 prevention in school settings is challenging.Implementing nonpharmaceutical measures and promoting vaccination programs in eligible staffand students should be considered.展开更多
文摘Background:SARS-CoV-2 clinical presentation is associated with the patients’age group.Overall,young indi-viduals present higher proportions of asymptomatic or mild COVID-19 infection,compared to adults.Data on secondary COVID-19 transmission in households,according to the cases’age group,are accumulating.Methods:We performed a follow-up cohort study including all COVID-19 real-time polymerase chain reaction(RT-PCR)-confirmed cases(adolescent students and school staff)diagnosed in an epidemiological investigation of a large high school outbreak.We compared the adolescent and adult groups regarding clinical symptoms,time to negative COVID-19 RT-PCR tests,and infection transmission in households.Results:The study population included 817 persons.The confirmed COVID-19 RT-PCR outbreak cases(n=178)were followed(students aged 12-19 years,median age 14 years,n=153,school staffaged 24-67 years,median age 39 years,n=25)and the cases’household close contacts(n=639)were tested.The adolescents had lower symptomatic infection rates,shorter time to negative COVID-19 RT-PCR tests,and lower transmission rates to household members,compared to the adults.The general transmission rate among household contacts was 13.5%,(86/639)ranging from 8.6%in asymptomatic students’contacts to 27.3%in symptomatic staffcontacts.COVID-19 transmission rates were significantly higher in contacts of symptomatic cases compared to asymptomatic cases(odds ratio:2.06,95%CI 1.26-3.4)and higher in adults compared to adolescents(odds ratio:2.69,95%CI 1.43-4.89).Conclusions:Adolescents and adults diagnosed in an outbreak investigation differ as to COVID-19 clinical presen-tation and transmission.As adolescents may show mild or no symptoms,COVID-19 prevention in school settings is challenging.Implementing nonpharmaceutical measures and promoting vaccination programs in eligible staffand students should be considered.
