英国伦敦卫生与热带医学院Rosalind M. Eggo、Nicholas G. Davies等研究人员合作揭示年龄对COVID-19传播和控制的影响。2020年6月16日，《自然—医学》在线发表了这一成果。

研究人员表示，COVID-19大流行中儿童病例的比例非常低。所见的病例中的年龄差异可能是由于儿童对感染的敏感性较低，或者是由于表现出临床症状的倾向较低，也可能是两者兼而有之。

Title: Age-dependent effects in the transmission and control of COVID-19 epidemics

Author: Nicholas G. Davies, Petra Klepac, Yang Liu, Kiesha Prem, Mark Jit, Rosalind M. Eggo

Issue&Volume: 2020-06-16

Abstract: The COVID-19 pandemic has shown a markedly low proportion of cases among children. Age disparities in observed cases could be explained by children having lower susceptibility to infection, lower propensity to show clinical symptoms or both. We evaluate these possibilities by fitting an age-structured mathematical model to epidemic data from China, Italy, Japan, Singapore, Canada and South Korea. We estimate that susceptibility to infection in individuals under 20 years of age is approximately half that of adults aged over 20 years, and that clinical symptoms manifest in 21% (95% credible interval: 12-31%) of infections in 10- to 19-year-olds, rising to 69% (57-82%) of infections in people aged over 70 years. Accordingly, we find that interventions aimed at children might have a relatively small impact on reducing SARS-CoV-2 transmission, particularly if the transmissibility of subclinical infections is low. Our age-specific clinical fraction and susceptibility estimates have implications for the expected global burden of COVID-19, as a result of demographic differences across settings. In countries with younger population structure-such as many low-income countries-the expected per capita incidence of clinical cases would be lower than in countries with older population structures, although it is likely that comorbidities in low-income countries will also influence disease severity. Without effective control measures, regions with relatively older populations could see disproportionally more cases of COVID-19, particularly in the later stages of an unmitigated epidemic. 

DOI: 10.1038/s41591-020-0962-9

Source: https://www.nature.com/articles/s41591-020-0962-9