WND EXCLUSIVE

RESEARCHERS: CAN'T STOP EBOLA WITHOUT TRAVEL BAN

Scientific analysis shows airport screening ineffective

Jerome R. Corsi

NEW YORK – A team of physicians with experience in epidemiology and health science research applying scientific methods and statistical analysis have concluded that as long as travel from West Africa remains open, there is no way to stop the international spread of Ebola.

The scientific analysis further demonstrates that as the number of Ebola cases in West Africa increases, as the World Health Organization has predicted, the risk of the disease spreading also rises.

The analysis, co-authored by a team of 18 physicians and health-care specialists, was published Monday under the title, “Assessment of the potential for international dissemination of Ebola virus via commercial air travel during the 2014 west African outbreak,” in the current issue of the peer-reviewed medical journal The Lancet.

Moreover, the analysis indicates that exit and entry passenger screening will produce negligible reductions in international travelers disseminating the disease, largely because Ebola’s incubation period of up to 21 days allows infected passengers to pass security undetected.

The CDC announced Wednesday it would begin monitoring all travelers from the West African nations of Guinea, Liberia and Sierra Leone for 21 days. But the monitoring requires self-reporting, relying on the travelers to check in each day in person or by telephone, Skype or Facetime or through employers.

On Oct. 1, WND reported a separate study published in the scientific journal PLOS Currents: Outbreaks that came to the same conclusion. It found that only a complete quarantine of air travel out of West Africa would prevent Ebola from going international, while a reduction in air travel of as much as 80 percent would only delay the international spread of the disease by three or four weeks at most.

Ebola-infected travelers

The authors’ methodology was to first quantify the total volume of commercial air travel out of Guinea, Liberia and Sierra Leone. Then, the data was adjusted for the reduction in total airline seat capacity resulting from flight cancellations and travel restrictions applied to the three countries Sept. 1.

Next, the authors obtained WHO estimates of the number of Ebola cases in each of the three countries and calculated an infection rate by dividing the number of cases by the estimated total population of the nation.

The number of outbound travelers likely to be infected with Ebola was then calculated by multiplying the monthly total number of international outbound air travelers by the Ebola infection rate calculated for each nation.

The study makes clear that as the number of outbound international travelers is reduced – for instance, by air travel restrictions imposed by other nations – the likelihood international air travelers would spread Ebola beyond West Africa decreases.

The following table shows the authors’ conclusion that an estimated 7.17 Ebola-affected international travelers per month depart West Africa under current rates of infection as long as outbound air travel remains unrestricted.

Source: The Lancet

Air travel risk projected to increase

In its most recent situation assessment, Oct. 17, WHO reported 1,519 Ebola cases in Guinea, 4,262 in Liberia and 3,410 in Sierra Leone, for a total of 9,193 cases.

The researchers calculated that in 2013, 0.2 percent of the world’s total commercial international air traffic was comprised of air travelers from Guinea (185,485), 0.2 percent from Sierra Leone (163,274) and 0.1 percent from Liberia (148,101).

There were 815 new reported Ebola cases in West Africa Oct. 17, compared to the Oct. 10 WHO report.

If WHO is correct that the Ebola outbreak in West Africa could produce 10,000 new cases each week by the end of the year, the number of infected international travelers could increase tenfold.

If the number of cases increased tenfold, the authors of the study estimate the cumulative number of outbound infected travelers between September and December 2014 would be 14.6 from Guinea, 160.5 from Liberia and 54.6 from Sierra Leone, assuming no new air travel restrictions are put in place.

Passenger screening not effective

The authors were skeptical of the ability of either exit screening at West African airports or entry screening at international destinations to reduce the number of Ebola-infected travelers.

A major problem is that the Ebola virus infection in the early stages has non-specific symptoms, with an incubation period that can take up to 21 days. It provides an infected Ebola traveler leaving West Africa up to a full three weeks in which to depart without symptoms of the disease being evident.

“The predictive value of a positive health screening would be extremely low,” the researchers concluded, “regardless of its sensitivity or specificity.”

The researchers discouraged reliance on enhanced exit screening:

“Hence, screening travellers on multi-segment flights to their final destination would probably have minimum benefits to unaffected countries but could incur important opportunity costs. Moreover, the short flight durations out of affected countries, compared with the much longer incubation period of Ebola virus, indicates that if exit screening from affected countries were implemented effectively, the incremental gains from additional entry screening would be negligible.”

The study further cautioned that exit screening may actually be counterproductive, because it “is likely to further draw on valuable health and human resources from resource-poor countries in the midst of an emergency.” The study said “support from the international community will be necessary to effectively implement these recommendations.”

Since most international air travelers from West Africa reach the United States though flights that connect out of Europe, the study warned that multiple possibilities for layovers at connecting destinations and the ability to connect to the U.S. on separately booked connecting flights complicates entry screening.

“Entry screening at international airports to which no direct flights are arriving from affected countries would be highly inefficient if border authorities are unable to easily identify which travellers originated from countries currently experiencing community-based Ebola virus transmission,” the study concluded.

Even more problematic are international travelers who remain for a time at the connecting destination in Europe and travel to the U.S. on a separate ticket that may enter any one of a dozen U.S. destinations. The CDC has selected five gateway airports for enhanced screening.

Training personnel to a high level of proficiency at all the entry destinations in the U.S. will be costly.

Zero risk requires a quarantine

The study also ran sensitivity measures involving reduction in air travel from West Africa of 50 to 75 percent. The results indicated that even with a 75 percent reduction, 3.7 outbound infected West African air travelers would leave Guinea between September-December 2014 should the incidence of the disease increase as fast as anticipated, plus another 40.1 outbound from Liberia and 13.7 from Sierra Leone.

The only restriction in air travel that reduced the risk to zero appeared to be a complete quarantine that stopped all commercial traffic out of the West Africa nations as long as the Ebola outbreak continues.

“As shown in our analysis and witnessed by the imported case of Ebola virus into Nigeria and the USA, the potential for further international spread via air travel remains present,” the researchers concluded.

“Of additional concern is that the anticipated destinations of more than 60% of travellers departing Guinea, Liberia, and Sierra Leone are to low-income or lower-middle income countries, where inadequately resourced medical and public health systems might be unable to detect and adequately manage an imported case of Ebola virus disease, including possible subsequent community spread.”

Read more at http://www.wnd.com/2014/10/researchers-cant-stop-ebola-without-travel-ban/#Se6e3mZXSHfe4PU4.99

My comments: This conclusion is only COMMON SENSE and Obama and the CDC know this. This REALITY leaves in question their MOTIVES for not stopping air travel from the infected nations.