Rickets was a common, even endemic, disease, and therefore not terribly difficult to study.

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While polio has been eliminated in much of the world, largely through mass immunization campaigns, the disease remains endemic in three countries: Pakistan, Nigeria and Afghanistan.

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Cholera could also be a problem, but the disease is not endemic on the island.

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"We believe it is definitely possible that we can eliminate the disease before it enters into a cycle and becomes endemic, " he said.

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No fewer than 2, 000 people return home with the disease each year as African holiday resorts in malaria endemic areas like Kenya and Gambia grow in popularity.

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But it said evidence revealed the general UK population was not at increased risk of TB, HIV or malaria infection from migrants, but some UK-born ethnic communities did have a higher risk of disease because of their links to countries where the diseases were endemic.

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