A private Bay Area Catholic high school is dealing with an outbreak of tuberculosis, according to city health officials and multiple media reports.
As of last week, there have been three active cases of the airborne bacterial infection that primarily affects the lungs, with the first case at Archbishop Riordan High School in San Francisco reported in November, KTLA’s sister station KRON reported.
Officials with the San Francisco Department of Public Health issued a Jan. 29 alert about the outbreak and said that more than 50 people in the school community have tested positive for latent TB.
A person with active tuberculosis experiences symptoms and can spread the infection to others. With latent TB, a person does not develop symptoms and is not infectious to others. Latent TB, however, can turn active at any time.
Health department officials urged health care providers seeing patients connected to the outbreak to look for signs of the infection.
Three active cases of tuberculosis have been identified since November 2025, and more than 50 people have tested positive for latent tuberculosis at a private school, Bay Area health officials said on Jan. 29, 2026. (Google Maps)
In an email obtained by SFGATE, school officials announced last week that in-person classes would be suspended and that students would study remotely through Feb. 9 with a transition model lasting through Feb. 20. Staff and students who test negative after that date will be allowed on campus, and only those who have tested negative will be able to attend indoor off-campus activities, including sports events.
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Tuberculosis outbreaks are relatively rare but, according to the California Department of Health, the state’s annual incidence rate was 5.4 cases per 100,000, which is almost double the national incidence rate.
The treatable bacterial infection tends to affect the respiratory system but can move into other organs, require hospitalization and be fatal.
Symptoms include fever, chills, coughing, coughing up blood and weight loss.
An infectious disease expert at the University of California, San Francisco, Dr. Monica Gandhi told SFGATE that there is a TB vaccine that’s not typically administered in the U.S.
The doctor added that the TB is easily transmissible in close settings and called the three active cases at the high school “really bad,” the outlet reported.
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