The Syrian Polio Outbreak Could Spread to Europe 'Undetected'

The polio outbreak happening in Syria might be about to get a whole lot worse, and could eventually threaten Europe, experts say.

In a paper published in The Lancet Thursday, Martin Eichner and Stefan O’Brockmann, epidemiologists in Germany, said that the massive numbers of refugees leaving war-torn Syria could spread the disease, essentially undetected. Countries such as Bosnia and Herzegovina, Ukraine, and Austria, which have relatively low polio vaccination rates, could be at most risk because “herd immunity might be insufficient to prevent sustained transmission.”

“Because only one in 200 unvaccinated individuals infected with [polio] will develop acute flaccid paralysis, infected individuals can spread the virus unrecognized,” they write.

It can take a long time for polio symptoms to develop, so Europe could be in for an devastating surprise even if the disease is undetected in the near future. “It might take … nearly one year of silent transmission before one acute flaccid paralysis case is identified and an outbreak is detected, although hundreds of individuals would carry the infection,” according to the paper.

Eichner and O’Brockmann say that more emphasis has to be placed on vaccinating Europeans against the disease. They say that merely vaccinating Syrian refugees, as has been recommended by the European Centre for Disease Prevention and Control, “must be judged as insufficient.”

In recent days, the World Health Organization has stepped up its efforts to stop the spread of polio in Syria and beyond. The organization recently suggested that more than 20 million children should be vaccinated against the disease in the Middle East. So far, WHO has detected at least 10 cases of polio in Syria this year. The disease was thought to be eradicated, and had previously not been detected since 1999. According to WHO, most of the affected individuals are two years old or younger and are “un- or under-immunized.” Vaccination rates in Syria declined from 91 percent in 2010 to 68 percent in 2012 as the country’s civil war has intensified.

“Given the current situation in the Syrian Arab Republic, frequent population movements across the region and subnational immunity gaps in key areas, the risk of further international spread of wild poliovirus type 1 across the region is considered to be high,” WHO said in a statement. But the civil war that made Syria's children vulnerable prevents health care workers from

Syria isn’t the only place where polio is increasingly becoming an issue. Due to Taliban bans on vaccination and attacks on health workers, Pakistan has seen an increase in polio, which puts worldwide eradication at risk. In 1985, there were 350,000 cases of the disease worldwide—by 2012, there were just 223. So far this year, there have been about 300 confirmed cases, 43 of them in Pakistan.