ABSTRACT
Age is among the strongest risk factors for severe outcomes from SARS-CoV-2 infection. We sought to evaluate associations between age and both mucosal and systemic host responses to SARS-CoV-2 infection. We profiled the upper respiratory tract (URT) and peripheral blood transcriptomes of 201 participants (age range of 1 week to 83 years), including 137 non-hospitalized individuals with mild SARS-CoV-2 infection and 64 uninfected individuals. Among uninfected children and adolescents, young age was associated with upregulation of innate and adaptive immune pathways within the URT, suggesting that young children are primed to mount robust mucosal immune responses to exogeneous respiratory pathogens. SARS-CoV-2 infection was associated with broad induction of innate and adaptive immune responses within the URT of children and adolescents. Peripheral blood responses among SARS-CoV-2-infected children and adolescents were dominated by interferon pathways, while upregulation of myeloid activation, inflammatory, and coagulation pathways was observed only in adults. Systemic symptoms among SARS-CoV-2-infected subjects were associated with blunted innate and adaptive immune responses in the URT and upregulation of many of these same pathways within peripheral blood. Finally, within individuals, robust URT immune responses were correlated with decreased peripheral immune activation, suggesting that effective immune responses in the URT may promote local viral control and limit systemic immune activation and symptoms. These findings demonstrate that there are differences in immune responses to SARS-CoV-2 across the lifespan, including between young children and adolescents, and suggest that these varied host responses contribute to observed differences in the clinical presentation of SARS-CoV-2 infection by age.
Subject(s)
COVID-19 , Severe Acute Respiratory SyndromeABSTRACT
Building a strong public health system has become an urgent task in the new era. Based on more than eight years of systematic research, we believe that five aspects need to be prioritized for a strong system. First, we should change the perspective on public health, using the word "gonggong jiankang" to replace "gonggong weisheng" and the word "gonggong jiankang tixi" to replace "gonggong weisheng tixi", to lead the public health system development. Second, we should develop a suitable public health system and continuously improve the health capacity for governance. Third, we should make it clear that the goal of building a strong system is not far-fetched, and we need to consolidate the existing institutional advantages of China's public health system: when encountering major problems, we can maintain a unified goal and mobilize the whole society to cooperate effectively to accomplish the goal. However, we need to make up for shortcomings one by one, especially to solve the key problem of lacking a strong coordination mechanism in daily work. Fourth, we should pursue excellence and consolidate the "suitable" mechanism proven in the process of coping with the COVID-19, so that efficient mechanisms to deal with major issues can be used in routine work, and efforts should be made to consolidate the advantages of prevention and control of infectious diseases and emergency response, so as to achieve the balanced development of regions categories and units. Finally, it is necessary to strengthen the coordination of government and research institutions, in the aspects of technological innovation, talent team building and accurate consulting services, and work together to pursue a suitable and strong system to realize the modernization of the health system and capacity for governance.