Coronavirus: flight bans are no guarantee of stopping the spread of the virus, epidemiologist warns
- ‘Borders cannot stop infectious diseases,’ says David Heymann, who led the World Health Organisation’s response to Sars epidemic in 2003
- More important to stopping the outbreak is the strength of a nation’s health care system, he said
“Borders cannot stop infectious diseases and you may have your eye on one border and one activity and the other activity escapes you and something comes in from another side,” David Heymann said at a briefing at Chatham House, an international policy think tank in London where he is a distinguished fellow.
“People think if they shut down air transport from certain flights they shut down transmission,” Heymann said.
“But what if an infected passenger changed planes in a country still coming in? They can still get into your country.”
Foreign nationals who have visited China in the 14 days before their arrival in the US are not allowed to enter the country, while returning US citizens who have been in Hubei province, the epicentre of the outbreak, will be subject to mandatory quarantine of up to two weeks.
But experts at Chatham House said a more important factor in stopping the spread of the disease was the strength and universality of a nation’s health care system, so that patients who may be showing symptoms could be immediately monitored and treated.
“Whether this virus continues to spread depends on how strong countries are within their own territories,” said Heymann, who is American.
Robert Yates, head of global health policy at Chatham House, said that countries most at risk from a rapid spread of the coronavirus are South Asian nations like Bangladesh and India or many African nations because of their governments’ low spending on health.
In China – where the outbreak originated in the city of Wuhan – the percentage with free access to public health had soared from a third of the population at the time of the Sars epidemic in 2002-03 to 96 per cent today, Yates said.
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That, he said, would help to curtail the current epidemic, which continues to set records. On January 29, Chinese health officials said the number of confirmed cases in mainland China had surpassed that of the Sars epidemic.
On Tuesday they said that fatalities had risen to 425 nationwide and that more than 20,700 cases had been confirmed worldwide.
As people in Hong Kong scramble to obtain enough protective masks, Heymann said that wearing them was effective in stopping those who had the virus from passing it on to others.
But there was scant scientific evidence that wearing a mask could prevent people from contracting the illness, he said.
“If you are sick it prevents you from sneezing or coughing in somebody’s face,” he said.
“A mask that is used to prevent yourself from getting an infection is sometimes not very effective because you take it off to eat, sometimes you might not wear it properly, if they get wet and someone sneezes on that mask it [the virus] could pass through.
“So there is really not a lot of evidence and I would think there is way too much wearing of masks.”
Separately, Public Health England issued a statement saying that results from a new sequencing of the novel coronavirus viral genome, using samples from Britain’s two confirmed coronavirus cases, showed that so far, the virus did not appear as though it was mutating and becoming more infectious.
