In a recent study published in the journal PNAS, researchers at the Johns Hopkins Bloomberg School of Public Health discovered that public health efforts to reduce tuberculosis transmission in geographic “hotspots” where infections are highest could significantly reduce TB transmission on a broader scale.
Researchers analyzed surveillance data from Rio de Janeiro and developed mathematical models for TB transmission in which each model tested different scenarios for transmission between the hotspot and the rest of the community. TB-HIV coinfection was also factored into the models.
They found that reducing TB transmission within three high-transmission hotspots could reduce citywide transmission by 9.8 percent over 5 years, and as much as 29 percent over 50 years.
In a press release from the Bloomberg School of Public Health, David Dowdy, MD, PhD, ScM, lead author of the study and assistant professor in the Bloomberg School’s Department of Epidemiology explained, “Targeting treatment of ‘core groups’ as a way to reduce community-wide transmission is common with diseases like HIV and malaria, but is less accepted as a mantra for TB control. Our findings suggest that hotspots containing 6 percent of a city’s population can be responsible for 35 percent or more of its ongoing TB transmission. Controlling TB in these hotspots may have a similar impact on long-term, community-wide TB incidence as achieving the same targets in the remaining 94 percent of the population.”