A new scientific study into the spread of Covid-19 has found that the level of international travel was the main factor in the severity of the first wave in spring 2020.
The study, Country-level determinants of the severity of the first global wave of the COVID-19 pandemic: an ecological study by Tiberiu Pana and colleagues at the Institute of Applied Health Sciences at the University of Aberdeen, looked at factors that might affect how hard countries were hit by Covid-19 in the period to June 2020. The research was published in the peer-reviewed BMJ Open journal.
The researchers looked at publicly available data on factors such as population and population density, percentage population living in urban areas, the percentage of the population older than 65 years, average body mass index and smoking prevalence, economic parameters, pollution levels and average temperature and others. The level of international travel to each country, using the number of international arrivals in 2018 as a guide to this, was one of the factors analysed.
Thirty-seven countries were included in the study, including the UK, US, France, Germany, the Netherlands, Finland and Sweden.
The authors said: “Out of all the country-level parameters assessed, international travel was the main determinant of the severity of the first global wave of the Covid-19 pandemic.”
It found a 3.4 per cent increase in the mean mortality rate due to Covid for every 1 million increase in the number of international arrivals.
The authors concluded: “Given that many of world middle-income and lower income countries are showing signs of continued rise in infection rates, international travel restrictions applied very early in the pandemic course should be considered to avoid rapidly increasing infection and death rates globally.”