Ebola Study Projects Spread of Virus

Ebola Study Projects Spread of Virus

 

Up to 3 Infected People Could Fly Overseas Every Month From Most-Affected African Nations

By Gautam Naik in the Wall Street Journal

Up to three Ebola-infected people could embark on overseas flights every month from the three most-affected African countries, according to a new study that projected travel patterns based on infection rates and recent flight schedules.

The findings, published Monday in the journal Lancet, suggest that Ebola cases could be spread overseas by unwitting travelers from the worst-hit countries—Guinea, Liberia and Sierra Leone.

The World Health Organization has estimated that, by early December, there could be as many as 10,000 new cases a week in west Africa.

The upshot is “that controlling the outbreak at the source is the most important thing that needs to happen” to prevent the international spread of the virus, said Kamran Khan, an infectious disease physician at St. Michael’s Hospital in Toronto and lead author of the study.

The researchers’ analysis assumed no exit screening in the airports of the three African nations. In reality, exit screenings occur, but the authors contend that this doesn’t change their conclusion because screenings can miss travelers who don’t yet show signs of Ebola. A person can incubate the virus for up to 21 days without exhibiting signs of the disease.

That was how Thomas Eric Duncan was able to board a flight from Liberia and show signs of the disease only after he landed in Dallas on Sept. 20.

The findings could stoke the debate about whether to implement a travel ban affecting Liberia, Sierra Leone and Guinea. Health experts have argued against a travel ban, maintaining that it won’t necessarily stop the spread of the virus and will stanch the flow of aid and health workers to a region that needs it most.

At least eight airlines have suspended some service during the past several months to Liberia, Guinea or Sierra Leone, said the charity Save the Children.

Air France , Brussels Airlines and Royal Air Maroc of Morocco are the three main passenger carriers still operating international flights to the hot zone. Over the weekend, Belgium, France and the U.K. said they were intensifying Ebola screening for passengers arriving at their main international airports.

Earlier this month, the U.S. added new screening measures at five airports on flights from Liberia, Guinea, and Sierra Leone. In New York, Chicago, Atlanta, Washington, D.C., and Newark, N.J., authorities check these travelers’ temperatures, health and potential exposure to Ebola, and collect their contact information while in the U.S. Those airports receive 94% of the roughly 150 passengers from these three countries who arrive in the country daily, officials said.

The Lancet study takes into account international flight restrictions that were in place to the three countries at the Ebola epicenter as of Sept. 1. Those restrictions led to a 51% drop in passengers for Guinea, 66% for Liberia and 85% for Sierra Leone.

After accounting for that level of decreased travel, the authors’ model projects that 2.8 passengers infected with Ebola would depart the three countries via commercial flights, on average, every month.

The projection by Dr. Khan and his colleagues suggests that about two-thirds of these travelers are expected to fly to low/ lower-middle income countries. This could pose a problem because poorer countries have fewer resources to identify and track infected people.

The two countries at highest risk of importing Ebola cases are Ghana and Senegal. Senegal has had one Ebola scare involving a person who traveled overland from Guinea.

The risk to European countries or the U.S. is considerably less, showed the study that was funded by the Canadian Institutes for Health Research. The research concludes that for every case exported to the U.S., there will be about eight cases exported to the U.K. and France combined.

The WHO played down the danger.

 

Posters comments:

1.  Who knows what to believe?
2. I am confident both opinions expressed in the Wall Street Journal (republished in this blog) are sincere.
3. And don’t forget the idea of “time phasing” of any action. In simple English, Ebola could spread to Europe first (as a pandemic) and later the USA as a pandemic.