(Wikimedia Commons)

Doctors said they fear that refugees escaping the fighting will bring the disease with them, and that countries with low immunization rates such as Austria, Bosnia and Ukraine are the most at risk.

The UN is trying to convince the Syrian government and rebel forces to instate a “vaccination ceasefire” to allow children to be inoculated. Estimates show that about half a million children have not had the vaccination.

But according to the Lancet, a health journal, vaccinations may not be enough.

Only one in every 200 unvaccinated people infected with polio will show signs, meaning the disease could spread in Europe for up to a year before cases with symptoms appear; at which point, it will be too late for any preventative measures.

The paper calls for routine searching for the virus in European sewage systems, as this method uncovered evidence of polio in Israel.

Polio symptoms are similar to those of the flu, except survivors experience effects that can last for decades, known as post-polio syndrome.

The disease is all but wiped out in most developed nations. 

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