Yeah, lots of outbreaks of plague since the C15th (including quite recently in Africa iirc), but not really as a major Europe-wide population decimator.
Put it on the policy list, I'm sure we can get a broad statement of intent through on population decimation following a plague outbreak causing a reversal in net migration as people flood back to mainland Europe to benefit from the increases in wages as a result.
London had the Plague 1665/66, it ended in the same year as the fire but it's not the fire that ended it. QI fact.