Covid 19

Epidemiological models

Authors	Publication date	Geographical region	Type	Description	Predictions
Chen et al	28.01.2020	Wuhan, China	SEIR (several species)	Model described virus transmission between bets (possible source), unknown host and human. For every species SEIR model is implemented. Simplified model with only human species is also considered.	The value of R0 was estimated of 2.30 from reservoir to person and 3.58 from person to person which means that the expected number of secondary infections that result from introducing a single infected individual into an otherwise susceptible population was 3.58.
Wu et al.	31.01.2020	Wuhan / China	SEIR	Model was created to reflect data obtained in Wuhan, then the model was extrapolated on China overall, taking into account cities connection with Wuhan and major routes of air and train transport	R0 for 2019-nCoV is 2.68, 75 815 individuals have been infected in Wuhan as of Jan 25, 2020. The epidemic doubling time was 6.4 days. Chongqing, Beijing, Shanghai, Guangzhou, and Shenzhen had imported 461, 113, 98, 111, and 80 infections from Wuhan, respectively. Epidemics are already growing exponentially in multiple major cities of China with a lag time behind the Wuhan of about 1–2 weeks. On the present trajectory, 2019-nCoV could be about to become a global epidemic in the absence of mitigation.To possibly succeed, substantial, even draconian measures that limit population mobility should be seriously and immediately considered in affected areas.
Danon et al.	14.02.2020	England and Whales	SEIR+Spatial	Authors used preexisted spatial metapopulation model to describe population movement between regions in England and Whales and standard SEIR model to describe Covid-19 spread in each particular region.	CoVID-19 outbreak will peak 126 to 147 days (~4 months) after the start of person-to-person transmission in England and Wales in the absence of controls, epidemic peak is predicted in June.
Westerhoff and Kolodkin	30.03.2020	Not specified	modified SEIR	Model distinguished between tested and non-testes subjects and takes into consideration adaptive government-induces social distancing policy	Strategies aiming for herd immunity are unacceptable and that a much stronger lockdown is required. Results suggest that the measures taken by many policy makers will be insufficient to quench the epidemic. Some Western policy makers engage in an adaptive lock down strategy but one of insufficient strength: model results suggest that their slowly increasing lock down strategy will not be effective. What is necessary is a strong lock down, which may then be softened as the number of infected individuals begins to decrease with time.
Tutu.ru	30.03.2020	Russian Federation	SIR + Spatial	Model uses dataset acquired by tutu.ru for movement statistics between nearly 170 000 Russian cities, villages and other inhabited localities. It investigates effects of restrictions on transition between cities on Covid19 spread. For each city simple SIR model is used.	Due to highly uneven population density (high in the western part and low in the eastern) it is possible to change epidemic timing by restricting movement between main transport hubs which will probably be economically justified in the future.
Chang et al.	02.04.2020	Australia	Agent-based	AceMod (The Australian Census-based Epidemic Model), containing 24 million agents, each of which represents individual with his own characteristics (gender, occupation, susceptibility) and social context. AceMod was previously developed and validated for simulations of pandemic influenza in Australia. Currently it was calibrated to describe covid-19 pandemic.	Effectiveness of school closures is limited, producing a two-week delay in epidemic peak, without a significant impact on the magnitude of the peak, in terms of incidence or prevalence. The temporal benefit of the two-week delay may be offset not only by logistical complications, but also by some increases in the fractions of both children and older adults during the period around the incidence peak. Social distancing (SD) strategy showed no benefit for lower levels of compliance (at 70% or less). Increasing a compliance level just by 10%,from 70% to 80%, may effectively control the spread of COVID-19 in Australia (during the suppression period).