Molecular epidemiology (3)
l BUT there is clustering among FB TB
El Sahly et al., 2001:  30% of FB TB in
Houston
Ellis BA et al., 2002:  35% of FB TB
l AR, MD, MS, MI, NJ, Dallas plus 3 Counties in
TX; and 6 Counties in CA
l Recent transmission?
l Limited genetic diversity in the country of
origin (founder effect)?