The migration of refugees leaving hostile and unsafe areas is nothing new. Heading to a new land to start a better life is the goal of many unfortunate families who are caught up in wars, political unrest and resource competition. Unfortunately, these people migrating can also carry diseases.
As government infrastructure collapses, health care programs stop. Vaccinations stop, access to medical care stops and communicable diseases can start to rise up. Unfortunately, this is why people need to consider leaving those areas!
A recent article looked at communicable diseases in the Syrian conflict here:
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4231133/
Concerns for waning vaccination protection against diseases such as measles, polio and meningitis in Europe should be examined. Increasing vaccine refusals over the last years have left a vulnerable population that was previously protected due to herd immunity. The herd is about to get a lot bigger.