Metropolitan Transit System (MTS) and public health officials reported possible exposure to active tuberculosis (TB) on certain bus and trolley lines in San Diego County from February 16 through August 15, as revealed by the County News Center. This follows prior TB case reports involving MTS riders during August and September 2022 and February 2023.
The impacted lines and routes have to been found by authorities, who highlight that the odds of specific riders having prolonged exposure are minimal, and the risk of contracting TB is highest for those with excessive indoor exposure to TB-infected individuals. Even though the risk is low, immunocompromised riders, such as those with HIV or on immune-suppressing medications, are at higher risk from limited exposures. Accordingly, the County and MTS are urging these individuals to stay alert and consult their medical providers.
As an airborne disease that cannot spread by touch, tuberculosis is a public health concern worth noting. Although MTS sanitation follows CDC guidelines, cleaning processes have no impact on TB transmission in transit vehicles or stations. Therefore, those who test positive for TB without active TB symptoms should have a chest x-ray and initiate a consultation with their medical provider. These individuals are likely carriers of the latent form of TB, which can be cured with treatment before it becomes active.
At present, no direct evidence linking the recent TB cases to prior MTS riders with TB have been discovered by the San Diego County Health and Human Services Agency. However, to ascertain any potential relations, additional lab tests will be performed. As per the County News Center, an estimated 175,000 San Diego County residents have latent TB and risk transitioning to active TB without preventive treatment. However, the active TB diagnoses have remained steady over the past few years, with 192 cases in 2020, 201 cases in 2021, and 208 cases in 2022.
Officially, active TB symptomatic individuals or immunocompromised individuals should seek medical assessment to rule out potential active TB infection and discuss available treatment options. To glean more information about this probable exposure incident, the County TB Control Program is also serving as an information outlet.
