CDC studies of registry data (1)
l McKenna MT, McCray E, Onorato I. The
epidemiology of TB among foreign-born
persons in the US, 1986-1993. (NEJM 1995).
55% of cases diagnosed < 5 yrs; 30% < 1 yr post-
arrival
More cases in younger immigrants than older
immigrants, but lower case rate:  cohort effect?
Largest relative difference between US-born and FB
TB rates is among aged <15 yrs
substantial recent transmission around time of
immigration (pre and post)