A five-compartment model of age-specific transmissibility of SARS-CoV-2

• Published in: Infectious diseases of poverty Vol. 9; no. 1; pp. 117 - 15
• Main Authors: Zhao, Ze-Yu, Zhu, Yuan-Zhao, Xu, Jing-Wen, Hu, Shi-Xiong, Hu, Qing-Qing, Lei, Zhao, Rui, Jia, Liu, Xing-Chun, Wang, Yao, Yang, Meng, Luo, Li, Yu, Shan-Shan, Li, Jia, Liu, Ruo-Yun, Xie, Fang, Su, Ying-Ying, Chiang, Yi-Chen, Zhao, Ben-Hua, Cui, Jing-An, Yin, Ling, Su, Yan-Hua, Zhao, Qing-Long, Gao, Li-Dong, Chen, Tian-Mu
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 26.08.2020; BioMed Central; BMC
• Subjects: Adolescent; Adult; Age Factors; Age groups; Age-specific dynamics; Aged; Analysis; Asymptomatic; Betacoronavirus - isolation & purification; Compartmental model; Coronavirus Infections - epidemiology; Coronavirus Infections - transmission; Coronaviruses; COVID-19; Disease transmission; Epidemiology; Female; Health aspects; Humans; Male; Middle Aged; Models, Statistical; Ordinary differential equations; Pandemics; Parameter estimation; Pneumonia, Viral - epidemiology; Pneumonia, Viral - transmission; SARS-CoV-2; Severe acute respiratory syndrome; Severe acute respiratory syndrome coronavirus 2; Transmissibility; Young Adult; Iran; China; Age-specific dynamics; COVID-19; Compartmental model; SARS-CoV-2; Transmissibility
• ISSN: 2049-9957; 2095-5162; 2049-9957
• DOI: 10.1186/s40249-020-00735-x

The novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, also called 2019-nCoV) causes different morbidity risks to individuals in different age groups. This study attempts to quantify the age-specific transmissibility using a mathematical model. An epidemiological model with five compartments (susceptible-exposed-symptomatic-asymptomatic-recovered/removed [SEIAR]) was developed based on observed transmission features. Coronavirus disease 2019 (COVID-19) cases were divided into four age groups: group 1, those ≤ 14 years old; group 2, those 15 to 44 years old; group 3, those 45 to 64 years old; and group 4, those ≥ 65 years old. The model was initially based on cases (including imported cases and secondary cases) collected in Hunan Province from January 5 to February 19, 2020. Another dataset, from Jilin Province, was used to test the model. The age-specific SEIAR model fitted the data well in each age group (P < 0.001). In Hunan Province, the highest transmissibility was from age group 4 to 3 (median: β  = 7.71 × 10 ; SAR  = 3.86 × 10 ), followed by group 3 to 4 (median: β  = 3.07 × 10 ; SAR  = 1.53 × 10 ), group 2 to 2 (median: β  = 1.24 × 10 ; SAR  = 6.21 × 10 ), and group 3 to 1 (median: β  = 4.10 × 10 ; SAR  = 2.08 × 10 ). The lowest transmissibility was from age group 3 to 3 (median: β  = 1.64 × 10 ; SAR  = 8.19 × 10 ), followed by group 4 to 4 (median: β  = 3.66 × 10 ; SAR  = 1.83 × 10 ), group 3 to 2 (median: β  = 1.21 × 10 ; SAR  = 6.06 × 10 ), and group 1 to 4 (median: β  = 7.20 × 10 ; SAR  = 3.60 × 10 ). In Jilin Province, the highest transmissibility occurred from age group 4 to 4 (median: β  = 4.27 × 10 ; SAR  = 2.13 × 10 ), followed by group 3 to 4 (median: β  = 1.81 × 10 ; SAR  = 9.03 × 10 ). SARS-CoV-2 exhibits high transmissibility between middle-aged (45 to 64 years old) and elderly (≥ 65 years old) people. Children (≤ 14 years old) have very low susceptibility to COVID-19. This study will improve our understanding of the transmission feature of SARS-CoV-2 in different age groups and suggest the most prevention measures should be applied to middle-aged and elderly people.