Tuberculosis cases on the rise in SLO County, health department warns. What to know

After a decade of exceptionally low numbers, tuberculosis seems to be on the rise in San Luis Obispo County.

In 2023, there were 10 local cases of active tuberculosis identified “after more than a decade of case counts in single digits,” San Luis Obispo Public Health said in a Wednesday news release.

The department stressed that the number of local cases still remain low.

Cases of latent tuberculosis — where bacteria hibernates in the body without causing illness — have also increased in recent years, the agency said.

“We’re very fortunate that tuberculosis is not common in our area and very effective treatment is available to stop latent TB from causing you harm,” County Health Officer Dr. Penny Borenstein said in the release, adding that residents who spend more than a month in a country where tuberculosis is more common should get tested even if they feel fine.

Treatment is available for both active and latent tuberculosis.

According to the public health department, symptoms of active tuberculosis include severe cough — sometimes with blood — night sweats, fever, weight loss and weakness or fatigue. People with active tuberculosis can spread it by coughing, talking or singing.

It spreads when people spend an extended time together, like living in the same household or sitting together on a long flight. A person will not spread tuberculosis by spending a few minutes in the same room as someone or having a short conversation on the street.

According to the agency, tuberculosis killed one in every seven people in the United States and Europe in 1882, the year the bacteria that caused the disease was identified. After decades of research, testing and treatment is now widely available and most people in the United States never encounter the disease.

Exposure to the disease causes people to develop latent tuberculosis in most cases, the health agency said, which does not cause symptoms and cannot spread to others.

Latent tuberculosis stays in the body and can later develop into active tuberculosis if it is not treated.

About 85% of tuberculosis cases in California are caused by latent tuberculosis developing into active tuberculosis, the agency said.