December 31, 2020 (Scientific Reports)

A model to rate strategies for managing disease due to COVID-19 infection

Shiyan Wang & Doraiswami Ramkrishna

https://doi.org/10.1038/s41598-020-79817-7

The authors demonstrate that when machine learning is employed together with the mechanistic framework of a mathematical model, there can be a considerably enhanced understanding of complex systems. A mathematical model describing the viral infection dynamics reveals two transmissibility parameters influenced by the management strategies in the area for the control of the current pandemic. Treatment of population data with the model shows that restricted non-essential business closure, school closing and strictures on mass gathering influence the spread of infection.

 

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December 31, 2020 (International Journal of Infectious Diseases)

Comparing COVID-19 vaccine allocation strategies in India: A mathematical modelling study

Brody H. Foy, Brian Wahl, Kayur Mehta et al.

​The authors used an age-structured, expanded SEIR model with social contact matrices to assess age-specific vaccine allocation strategies in India. They used state-specific age structures and disease transmission coefficients estimated from confirmed incident cases of COVID-19 between 1 July and 31 August 2020. Simulations were used to investigate the relative reduction in mortality and morbidity of vaccine allocation strategies based on prioritizing different age groups. They showed that prioritizing COVID-19 vaccine allocation for older populations (i.e., >60 years) led to the greatest relative reduction in deaths, regardless of vaccine efficacy, control measures, rollout speed, or immunity dynamics. Their findings support global recommendations to prioritize vaccine allocation for older age groups.

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December 30, 2020 (Scientific Reports)

Rapid and complete inactivation of SARS-CoV-2 by ultraviolet-C irradiation

Nadia Storm, Lindsay G. A. McKay, Sierra N. Downs et al.

https://doi.org/10.1038/s41598-020-79600-8

In this paper, the researchers describe the inactivation of SARS-CoV-2 in both wet and dry format using ultraviolet (UV)-C light source at 254 nm. They show that for contaminated surfaces, only seconds of exposure is required for complete inactivation, allowing for easy implementation in decontamination workflows.

 

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December 24, 2020 (Applied Soft Computing)

COVID-19 X-ray images classification based on enhanced fractional-order cuckoo search optimizer using heavy-tailed distributions

Dalia Yousri, Mohamed Abd Elaziz, Laith Abualigah et al.

https://doi.org/10.1016/j.asoc.2020.107052

The researchers propose a method that extracted the informative features from X-ray images. An enhanced cuckoo search optimization algorithm is proposed using fractional-order calculus and four different heavy-tailed distributions in place of the Lévy flight to strengthen the algorithm performance during dealing with COVID-19 multi-class classification optimization task. The results were compared with well-regarded optimization algorithms. The outcomes show that the proposed approach yield accurate results for UCI and COVID-19 data-sets.

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December 24, 2020 (Results in Physics)

A simple, SIR-like but individual-based epidemic model: Application in comparison of COVID-19 in New York City and Wuhan

Xiaoping Liu

https://doi.org/10.1016/j.rinp.2020.103712

An individual-based epidemic model, considering latent-infectious-recovery periods is presented. The analytic solution of the model in the form of recursive formulae with a time-dependent transmission coefficient is derived. The simulated epidemic curves fit very well with the daily reported cases of COVID-19 in Wuhan, China and New York City (NYC), USA. These simulations show that the transmission rate of NYC’s COVID-19 is nearly 30% greater than the transmission rate of Wuhan’s COVID-19. 

 

 

December 24, 2020 (Environmental Research)

Phase-wise analysis of the COVID-19 lockdown impact on aerosol, radiation and trace gases and associated chemistry in a tropical rural environment

Chaithanya D. Jain, B. L. Madhavan, Vikas Singh et al.

https://doi.org/10.1016/j.envres.2020.110665

Phase-wise variations in different aerosol, radiation and trace gases and their associated chemistry during the COVID-19 lockdown have been investigated over a tropical rural site Gadanki, India. In contrast with the studies over urban environments, air quality category over the rural environment remained the same during the lockdown despite the reduction in pollutants level. All the variations observed for different species and their associated chemistry demonstrates rural atmospheric chemistry and its intrinsic links with the precursor concentrations and dynamics.

 

 

December 23, 2020 (Infectious Disease)

Assessment of Air Contamination by SARS-CoV-2 in Hospital Settings

Gabriel Birgand, Nathan Peiffer-Smadja, Sandra Fournier et al.

http://doi.org/10.1001/jamanetworkopen.2020.33232

This paper reviews current evidence on air contamination with SARS-CoV-2 in hospital settings and the factors associated with contamination, including viral load and particle size. The positivity rate of SARS-CoV-2 viral RNA and culture were described and compared according to the setting, clinical context, air ventilation system, and distance from patients. High viral loads found in toilets and bathrooms, staff areas, and public hallways suggest that these areas should be carefully considered.

 

 

December 17, 2020 (Environmental Research)

Did anomalous atmospheric circulation favor the spread of COVID-19 in Europe?

A. Sanchez-Lorenzo, J. Vaquero-Martínez, J. Calbó et al.

​Lorenzo et al show that an unusual persistent anticyclonic situation prevailing in southwestern Europe during February 2020 (i.e. anomalously strong positive phase of the North Atlantic and Arctic Oscillations) could have resulted in favourable conditions in Italy and Spain for a quicker spread of the virus compared with the rest of the European countries. They suggested that the strong atmospheric stability and associated dry conditions may have favoured the virus propagation by droplet and airborne transmission. Later atmospheric circulation conditions in Europe (July 2020) and the U.S. (October 2020) seem to support their hypothesis. Interestingly, they pointed out the atmospheric conditions during the Spanish flu pandemic in 1918 seem to have some similarities with the current COVID-19 pandemic.

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December 17, 2020 (Environmental Research)

Did anomalous atmospheric circulation favor the spread of COVID-19 in Europe?

A. Sanchez-Lorenzo, J. Vaquero-Martínez, J. Calbó et al.

https://doi.org/10.1016/j.envres.2020.110626

In this study the authors show that an unusual persistent anticyclonic situation prevailing in southwestern Europe during February 2020 could have resulted in favorable conditions. It seems possible that the strong atmospheric stability and associated dry conditions that dominated in these regions may have favored the virus propagation by short-range droplet and aerosol (airborne) transmission, or/and by changing social contact patterns. Subsequent atmospheric circulation conditions in Europe (July 2020) and the U.S. (October 2020) seem to support their hypothesis.

 

 

December 11, 2020 (Results in Physics)

Modeling and prediction of COVID-19 spread in the Philippines by October 13, 2020, by using the VARMAX time series method with preventive measures

Parikshit Gautam Jamdade & Shrinivas Gautamrao Jamdade.

​The authors examined the characteristics of COVID-19 affected populations based on the data provided by WHO from December 31, 2019, to September 13, 2020. In this paper, forecasts, and analysis of the COVID-19 cases, deaths, cases per million, and deaths per million were presented for 30 days ahead. The projection results are compared with the actual data values and simulated results from the VARMAX time series method. They suggested Philippines governments must rapidly mobilize and make good policy decisions to mitigate the spread.

 

         

December 10, 2020 (Scientific Reports)

Tracking the early depleting transmission dynamics of COVID-19 with a time-varying SIR model

Kian Boon Law, Kalaiarasu M. Peariasamy, Balvinder Singh Gill et al.

​The authors modified the SIR model to simulate the early depleting transmission dynamics of COVID-19 to better predict its trend in Malaysia. The classical SIR model was fitted to observed total, active and removed cases before lockdown to estimate the basic reproduction number. They then modified the model with a partial time-varying force of infection. The modified SIR model was used to analyse observed data over 6 weeks during the lockdown.They concluded that the depleting transmission dynamics during lockdown can be accurately captured by the time-varying SIR model.

 

 

December 10, 2020 (Scientific Reports)

Multidisciplinary approach to COVID-19 risk communication: a framework and tool for individual and regional risk assessment

Rishi Ram Parajuli, Bhogendra Mishra, Amrit Banstola et al.

​This paper presents a framework to assess the individual and regional risk of COVID-19 along with risk communication tools. Relative risk scores on a scale of 100 represent the integrated risk factors. The personal risk model includes age, exposure history, symptoms, local risk and existing health condition, whereas regional risk is calculated through the actual cases of COVID-19, public health risk factors, socioeconomic condition and immigration statistics. A web application tool (http://www.covira.info) was developed for one to assess the risk and find the information links primarily for Nepal. This study provides regional risk for Nepal, but the framework is scalable for other countries.

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