Why the Bay Area has been a tuberculosis hotspot for more than a century

"We have a large reservoir of people with (latent tuberculosis infections), and they should be tested and treated. But they're not, for a variety of reasons. This statement from Dr. Amit Chitnis, tuberculosis controller for the Alameda County Public Health Department, highlights the critical gap in TB management where infected individuals remain untreated despite the availability of interventions."

"The Bay Area has long been an epicenter for the disease on the West Coast because of its ports and as an immigration checkpoint for migrants from places such as Asia and Latin America. This geographic and demographic reality explains why the region experiences tuberculosis rates as high as three times the national average."

"More than 90% of active cases in the Bay Area now occur among immigrants that have come from countries that lack easy access to vaccines, according to Stanford tuberculosis researcher Jason Andrews. The rate is highest among people born in the Philippines and Vietnam. This demonstrates the direct correlation between immigration patterns and TB prevalence in the region."

The Bay Area, particularly Alameda, Santa Clara, San Francisco, and San Mateo counties, experiences tuberculosis rates significantly higher than the national average. Over 200 high school students in San Francisco recently contracted TB, highlighting the disease's persistent presence in the region. The Bay Area's status as a major port and immigration checkpoint has historically made it an epicenter for tuberculosis transmission. While current screening identifies active infections, latent TB cases often go undetected among immigrants. Over 90% of active TB cases in the Bay Area occur among immigrants from countries lacking adequate vaccine access, with highest rates among people from the Philippines and Vietnam. Despite being rare compared to developing nations, tuberculosis became the deadliest infectious disease globally in 2023.

Read at The Mercury News