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Comment
. 2020 Aug;28(8):1375-1377.
doi: 10.1002/oby.22881.

A Primer on COVID-19 Mathematical Models

Diana M Thomas  1 , Rodney Sturdivant  2 , Nikhil V Dhurandhar  3 , Swati Debroy  4 , Nicholas Clark  1
Affiliations
Comment

A Primer on COVID-19 Mathematical Models

Diana M Thomas et al. Obesity (Silver Spring). 2020 Aug.
No abstract available

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Figures

Figure 1
Figure 1
Transition from the three possible states, susceptible St, infected, It, and removed Rt. The proportion of interactions between individuals in St and It that lead to infection per unit time is r, and the proportion of infected individuals that recover with immunity or die from disease per unit time is γ. The total number of individuals within the system remains constant throughout calculation.
Figure 2
Figure 2
Varying assumptions can alter the dynamic projection model outcomes. Assuming there is a time lag shifts the curve. Including social distancing that increases with increased infective populations and decreases with declining infected populations “flattens the curve” and results in an asymmetric projection. The parameter values were set with total population set as 1,000 individuals, r=0.02,γ=0.01. For the time lag model, the time lag for infection was set at τ=7 days and the time lag to mortality at 3 days. For the model where r is represented by the Hill function, K=30,βmax=0.85 and n=3.1.
Figure 3
Figure 3
The effective reproduction number REt, sometimes referred to as R0 or “R naught,” for New York fit to data with an exponential curve. REt represents the average number of secondary cases because of one infected person at the beginning of the epidemic, and in order for the epidemic to decline, REt should be less than 1. The points are the calculated daily effective reproduction number calculated by number of observed cases divided by the number of expected cases on a given day, while the gray curve forecasts future effective reproduction numbers that can be used in dynamic projection SIR models. Here, REt went below 1 (represented by the dashed line) around 28 days.
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References

    1. Lai CC, Shih TP, Ko WC, Tang HJ, Hsueh PR. Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) and coronavirus disease‐2019 (COVID‐ 19): The epidemic and the challenges. Int J Antimicrob Agents 2020;55:105924. doi:10.1016/j.ijantimicag.2020.105924 - DOI - PMC - PubMed
    1. Ryan DH, Ravussin E, Heymsfield S. COVID 19 and the patient with obesity ‐ the editors speak out Obesity (Silver Spring). 2020;28:847. - PMC - PubMed
    1. Richardson S, Hirsch JS, Narasimhan M, et al. Presenting characteristics, comorbidities, and outcomes among 5700 patients hospitalized with COVID‐19 in the New York City area. JAMA 2020;323:2052‐2059. - PMC - PubMed
    1. Bui Q, Katz J, Parlapiano A, Sanger‐Katz M. What 5 coronavirus models say the next month will look like. New York Times. April 20, 2020.
    1. Jewell NP, Lewnard JA, Jewell BL. Predictive mathematical models of the COVID‐19 pandemic: underlying principles and value of projections [published online April 16, 2020]. JAMA. doi:10.1001/jama.2020.6585 - DOI - PubMed

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