Many countries have implemented lockdown in an effort to contain the Covid-19 pandemic. Part of this strategy has been travel restrictions and bans, and, according to a new study by computer modelling experts at Stanford University, millions more people across the European Union could have contracted the disease had these international travel bans not been enforced.
The report, published in Computer Methods in Biomechanics and Biomedical Engineering, utilised a newly developed mathematical epidemiology simulation which calculated the consequences of limiting air travel across the 27 EU states on the spread of Covid-19.
The simulation was able to estimate figures for the spread of Covid-19 for each country, if travel bans were removed.
New model may influence political decision making
Since the team involved in the study can virtually lift travel restrictions between individual communities, states, or countries, and therefore analyse the potential gradual changes in spreading patterns and outbreak dynamics, their new model could play a significant role in political decision-making, one of the researchers said.
“Our results demonstrate that mathematical modelling can provide guidelines for political decision making with the ultimate goal to gradually return to normal while keeping the rate of new Covid-19 infections steady and manageable."
As of 18 April, flights were reduced by 95% in Spain, 94% in Italy, 93% in France, and 89% in Germany. The study’s graphs demonstrate how the spread of the novel coronavirus has been contained since then.
"Strikingly, our results suggest that the emerging pattern of the Covid-19 outbreak closely followed global mobility patterns of air passenger travel," explained Kuhl.
"Our results suggest that unconstrained mobility would have significantly accelerated the spreading of Covid-19, especially in Central Europe, Spain, and France."
Travel bans introduced too late
The model also reveals how travel bans were introduced too late to stop the Europe-wide outbreak altogether.
"A recent study based on a global metapopulation disease transmission model for the Covid-19 outbreak in China has shown that the Wuhan travel ban essentially came too late, at a point where most Chinese cities had already received many infected travellers," Kuhl added.
“Our study shows a similar trend for Europe, where travel restrictions were only implemented a week after every country had reported cases of Covid-19. As a natural consequence, unfortunately, no European country was protected from the outbreak."
By early March, there were 13 944 active cases within the EU – and the number only doubled every three to four days. As of 6 May, at the time of publishing this article, the 27 nations had a combined total of just over 1 million confirmed cases, according to the Johns Hopkins Coronavirus Resource Centre.
Kuhl added that their findings indicate that "mobility is a strong contributor to the global spreading of Covid-19", but acknowledged that air travel is not the only determinant of the outbreak dynamics.
The South African government has also enforced both local and international travel bans amid Covid-19. Under draft regulations, domestic flights (in special circumstances) will only be allowed from level 3 of lockdown, reports Business Insider.