Current Speculations on the Low Incidence Rate of the COVID-19 among Children

First reported in Wuhan, China on December 2019, the coronavirus disease 2019 (COVID-19) is a contagious viral infection of the respiratory system caused by SARS-CoV-2 (1). As of April 26, 2020, more than 2.5 million people have contracted the disease with nearly 200,000 deaths (2). The data published on the mortality and morbidity of the disease suggest that children under 10 years of age are generally less vulnerable to the virus and are usually asymptomatic or show milder symptoms (3). On the other hand, adults and the elderly, particularly those with underlying health conditions, appear to be more susceptible to the disease (4). It is not clear why children are more immune to COVID-19. However, we have an idea which we would like to share with the general public and scientific communities, hoping this would hinder the further spread of the disease.