This paper summarises a public health intervention in Sydney, NSW in late 2006 that resulted from the potential exposure of a number of refugees to polio virus while in transit in Nairobi, Kenya. The intervention involved the attempted follow-up of 113 persons at risk, assessment for symptoms and immunisation where indicated. No symptomatic cases were found. Seventy-five people were immunised with inactivated poliomyelitis vaccine. The intervention highlighted the importance of close collaboration between health services, the Department of Immigration and Citizenship and settlement service agencies, and provided several lessons to consider when assessing newly arrived refugees.