• Charles Sturt University research studied six nations - Australia, Italy, Spain, the USA, the UK, and Canada - to estimate parameters from 15 February to 30 March 2020
• The transmission rate of COVID-19 had the most significant influence on the prevalence
• The research suggests the most feasible and optimal strategy to eliminate COVID-19 in the six countries is to reduce contact rates as well as increase the treatment rate

The findings of a Charles Sturt University-led study could help limit or reduce COVID-19 infection and mortality rates in countries around the world.

The researchers said their findings could help the decision-makers in various organisations, including Ministries of Health, to control COVID-19, particularly in the six nations studied - Australia, Italy, Spain, the USA, the UK and Canada.

The research findings suggest that the most feasible and optimal strategy to eliminate COVID-19 in the six countries is to reduce contact rates and increase treatment rates.

The study was conducted by Associate Professor in Mathematics and Statistics Azizur Rahman in the Charles Sturt School of Computing, Mathematics and Engineering and his colleague Assistant Professor Md Abdul Kuddas in the Department of Mathematics at the University of Rajshahi in Bangladesh.

Their findings were recently published in the paper ‘Modelling the Transmission Dynamics of COVID-19 in Six High Burden Countries’ in the BioMed Research International (volume 2021, article ID 5089184, 17 pages, on 2 June 2021).

Within the six selected countries, they found that Spain has a higher transmission rate than the other countries, which may increase the massive number of COVID-19 cases and make it one of the worst situations in Spain.

“The Spanish government may not have taken proper action at the initial stage to control transmission, including handwashing, social distancing and good respiratory hygiene,” Professor Azizur said.

“For instance, in China, they took immediate action for transmission control, including lockdown in every city. That is how they were able to minimise the outbreak of COVID-19.

“Our finding is consistent with such typical observations because COVID-19 mainly spreads from person to person through droplet transmission. Droplets cannot go through the skin and can only lead to infection if they touch the mouth, nose or eye.

“Therefore, it is essential to protect susceptible individuals from COVID-19 exposure from a public health perspective by effectively reducing the contact rate between susceptible and infectious individuals.”

Professor Azizur said age is a significant risk factor that can increase the severity of the outbreak of COVID-19, with their study finding that adults are more infected than children and older people.

“Modelling studies have found that children are less likely to acquire an infection and are much less likely to show symptoms, similar to our results in Italy, Spain, the UK, and Canada, but dissimilar in Australia and the USA. This information will assist policymakers in strategy development,” he said.

“Estimation of transmission rates from different settings must be done with caution, though, as the pattern of a pandemic, the standard of care, and, as a result, the number of cases, are time and setting dependent.

“However, to control this global pandemic disease, the application of the proposed model and its related outputs can be extended to many other countries dealing with such a critical outbreak of COVID-19.”