It is useful to consider migration to the UK from the perspective of transnationalism, defined as "the process by which immigrants forge and sustain multi-stranded social relations that link together their societies of origin and settlement" 37 . From the 1920s until recently, migration research has tended to focus on the incorporation of migrants in their destination country rather than continued ties with their country of origin. However, since the 1990s, "the transnational turn" has provided "a new analytic optic" 38 . From this perspective, given that migrants maintain ties across the borders of nation-states, return visits to their country of origin and overseas visitors to the UK may result in increased exposure to M.tb. Where **data** was available, 17.2% of TB cases in 2016 in England had travelled outside the UK (excluding Western Europe, US, Canada, New Zealand and Australia) in the two years before diagnosis, and 7.3% had received an overseas visitor. 23.3% of non-UK born cases had travelled outside the UK in 2016 compared with only 4.7% of UK born cases 14 . Such movements are increasing as globalisation leads to the intensification of international interconnectedness: in the UK, travel to visit family and friends abroad increased by 67% between 1998 and 2007 39 . In 2007, UK residents made nearly 900,000 trips to the ISC for the purpose of visiting friends and family 39 .