A Mini Review on Current Clinical and Research Findings for Children Suffering from COVID-19

Xiao Li; Kun Qian; Ling-ling Xie; Xiu-juan Li; Min Cheng; Li Jiang; Bjoern W. Schuller

To our best knowledge on COVID-19, among the patients confirmed with COVID-19, the population of pediatric patients is rather small [4] . The children confirmed with COVID-19 mostly have good prognosis. A single child patient passed away; for other child patients, progression of the disease was observed as mild [9, 10] . Yet, in more general, infectious diseases often tend to behave less aggressively in child patients. For severe respiratory distress syndrome (SARS), the total death ratio is reported within 7% to 17%. For individuals with less than 24 years of age, the death ratio is 0% compared to 50% mortality rates in adults older than 65 years [9] . Looking at those cases of COVID-19 judged as severe, children's rate is also considerably below adults' rate (49.0%, 1023/2087) [19] . The main explanation would be:1. One possible reason is that children have been protected well resulting in lower potential exposure with the virus due to considerably lower travelling track record and potentially relatively higher indoor time. 2. Children possess more active innate immune systems, including mostly fully functional lungs owing to low exposure to smoking induced and other air pollution. 3. Children do not really have complex underlying disorders. 4.The differences in distribution, maturation and function of viral receptor angiotensin converting enzyme II (ACE2) are usually named a potential cause for age-based differences in infection rate. ACE2 was already considered a cell receptor for SARS-CoV [9] . Recent reports indicate that ACE2 in ciliated bronchial epithelial cells and type II pneumocytes is also likely the binding receptor for SARS-CoV-2. A usual theory for children's lower sensitivity to SARS-CoV-2 is based on their less maturity and lower function of ACE2 compared with that in adults [9] .