On May 5, the World Health Organization declared the end of the COVID-19 pandemic. For three years, countries tried to contain the spread of the disease by closing their borders. Did it help?
Building on experience
At the start of the COVID-19 pandemic, international organizations did not have a single protocol on how to stop the spread of the disease. A physical barrier—closed borders—seemed like an obvious first step. Scientists have looked to past epidemics to evaluate the effectiveness of this approach.
So, in January 2020, a University of Washington and Johns Hopkins study was published on whether travel bans are effective during epidemics. Scientists analyzed 4 dangerous recent infections: Ebola virus, SARS, MERS, and Zika virus.
According to the analysis, the travel ban could delay the entry of the infection into the country by days or weeks. But there is very little evidence that this eliminates the risk of spread in the long run. In addition, the ban is applied together with other control measures, and it isn’t easy to assess their impact separately.
African experience
Another study on the impact of border closures on the incidence of COVID-19 was conducted for nine countries in Africa in October 2021. The authors of the article, published in the Journal of the Royal Society for Tropical Medicine and Hygiene, studied the situation in Egypt, Tunisia, the Democratic Republic of the Congo, Ethiopia, Kenya, Ghana, Nigeria, Senegal, and South Africa.
What is the result? All countries have seen an increase in coronavirus cases since border closures. The researchers conclude that the isolation of states had a minimal impact on the incidence of COVID-19. This measure alone is not enough to contain the epidemic, other methods of control are needed.
Effect in the moment, but not in the future
At the beginning of 2022, a major international study was published in the journal Nature, which relied on data from the past two years. Its authors aimed to study whether the closure of borders has reduced the spread of coronavirus worldwide.
Scientists analyzed more than 1,000 entry restrictions imposed since 2020, as well as a few data from past epidemics. The historical review showed that if the borders were closed immediately, the transmission of the virus to the country would be delayed by several days or weeks.
At the same time, the researchers did not find evidence that the closure of international borders reduced the spread of COVID-19. The most surprising discovery was that the disease did not stop even on islands and territories that were completely quarantined. But scientists found that restrictions on movement within countries contributed to a decrease in new cases of infection.
But what about China?
China managed to tame the initial outbreak in Wuhan by completely locking down the city of more than 10 million people. Since then, Beijing has introduced the world’s toughest “zero tolerance” policy for COVID-19. However, for three years, foci of the disease continue to flare up in different parts of the country.
After public protests last year, China began to lift covid restrictions, which led to a sharp increase in cases. In December 2022, almost 250 million people were infected with the coronavirus there, there are deaths.
Despite the unprecedented drastic measures, the lockdown has not helped China stop the epidemic. According to the Chinese Foreign Ministry, in 2023 “the situation with COVID is under control.”
Too expensive measure
One of the most recent global studies from the University of York came out this year, and it also questions the effectiveness of border closures due to the coronavirus.
Canadian scientists compared data from 166 countries that closed during the first 22 weeks of the pandemic. The study found that targeted restrictions aimed at travelers did little to contain the infection. But the complete closure of the borders slowed the spread of COVID-19, but at a very high price.
“Travel restrictions have a diminishing effect if the domestic transmission is high if highly contagious strains are widespread worldwide, or if there are many people exempt from travel bans, quarantines, and testing,” the authors note.
If the restrictions had been held at the maximum level for longer, with fewer exceptions, they could have curbed the transmission of viruses, but it would have been too costly, the researchers said.