Divergence in pace of decline in tuberculosis rates among migrants versus non-migrants in Ireland from 2011 to 2020

Despite declining tuberculosis crude incidence rates (CIRs) in Ireland, the CIR among migrants remains five times higher than among non-migrants. We analysed notifications from the Irish tuberculosis surveillance system to compare the epidemiology of active tuberculosis among migrants with non-migrants in Ireland from 2011 to 2020 to inform future prevention and control strategies.We analysed cases by individuals, place, and time, defining migrants as being diagnosed in Ireland and born outside Ireland. We calculated CIRs per 100 000 population using population denominators stratified by country of birth, defining high tuberculosis incidence as more than 40 per 100 000 population. We did temporal trend analysis using negative-binomial regression.A total of 3158 cases were notified, of which 1461 (46·3%) were migrants. Annual CIRs declined from 25·2 to 13·6 per 100 000 population among migrants (incidence rate ratio [IRR] 0·95 [95% CI 0·94-0·97]) and from 5·6 to 1·8 per 100 000 population among non-migrants (0·91 [0·89-0·93]). Median age was 34 years among migrants and 53 years among non-migrants. Male-to-female ratio was 1·3 among migrants and 1·7 among non-migrants. Migrants had significantly higher odds of any drug resistance (odds ratio [OR] 1·7 [95% CI 1·2-2·6]), multidrug resistance (19·4 [5·0-166]), and HIV co-infection (4·0 [2·5-6·9]), but lower odds of being linked to an outbreak (OR 0·28 [95% CI 0·21-0·37]) or sputum positive (0·76 [0·61-0·93]). Migrants originated from 96 countries, 82% originated from high tuberculosis incidence countries compared with 23% of the Irish population. The top ten migrant source countries differed when ranked by case numbers versus CIR. Four countries had a higher CIR in Ireland than in those reported by WHO for their country of origin.The pace of tuberculosis decline in migrants is slower than in non-migrants, with elevated CIRs among migrant subpopulations that might indicate underserved communities. A renewed focus on migrant health strategy is required to achieve the global tuberculosis elimination goal.Health Service Executive, Ireland.