[bennyhill]

When we are only talking about a few samples in each group, 4 cases every few years seems fine.. I would hypothesize that many of the symptomatic cases are people who are foreign but exposed to UK endemic leprosy. Of course to establish how true that is means there are more data points to collect for cases with foreign contact and the involved lands.

[bastawhiz]

I looked it up before I posted, and it's actually the opposite: the overwhelming majority of cases are from visitors to the UK who contracted the illness outside the country. The last confirmed case of leprosy being contracted in the UK was in 1953.