San Diego County Reports Additional Tuberculosis Exposure Window at Southwest High School, Notifications Expand to Students, Staff

What the county says happened

San Diego County public health officials have reported an additional tuberculosis (TB) exposure window connected to Southwest High School, expanding outreach beyond a previously disclosed period earlier in 2025. The county said it is notifying students and staff who may have been exposed during a timeframe in fall 2025.

The newly reported potential exposure window spans Sept. 23, 2025, through October 2025, as described in a county update released this week. The county has not publicly identified the individual involved, consistent with medical privacy protections, and has not described any broad risk to the general public outside identified school contacts.

Earlier exposure period at the same campus

This development follows a prior county notification that potential exposure at Southwest High School may have occurred earlier in 2025, from Feb. 1, 2025, through May 22, 2025, during the previous school year. County records from mid-2025 indicate that individuals assessed to be at the highest risk of infection were notified first and that no-cost screening was arranged for students and staff considered to have elevated exposure risk.

How TB exposure notifications typically work

TB is caused by the bacterium Mycobacterium tuberculosis and most often affects the lungs. Public health follow-up after a potential school exposure generally focuses on people with prolonged, close, indoor contact with an infectious case. Those who receive notification are typically advised to complete TB testing, and, if a test is positive, to undergo further medical evaluation such as symptom screening and imaging to rule out active disease.

Public health messaging in similar school-related investigations emphasizes that many people who become infected do not feel sick right away. A positive test without symptoms can indicate latent TB infection, which is not contagious but can progress to active disease without treatment.

Steps being taken and what families can do

For both the earlier 2025 exposure period and the newly reported fall 2025 window, the county has described a coordinated response with the Sweetwater Union High School District centered on contact notification and targeted screening for those most likely to have had meaningful exposure.

• Students and staff identified for follow-up are being contacted directly with instructions for testing and next steps.
• No-cost screening has been arranged for those assessed to have increased exposure risk.
• Families who receive a notification are encouraged to complete testing on the timeline provided, since TB tests may be most informative weeks after the last potential exposure.

If you receive an exposure notice, testing and follow-up are aimed at identifying latent infection early and preventing progression to active TB disease.

County officials have directed people seeking details about the Southwest High School investigation to contact the County TB Control Program at 619-692-8621.