Nearly a dozen tuberculosis cases linked to Northern California casino in past 5 years; testing urged

A casino in Northern California has been linked to 11 tuberculosis cases over the past five years, prompting health officials to encourage both workers and visitors to get tested for what the World Health Organization calls “one of the world’s top infectious killers.”

Of the confirmed cases of the infectious bacterial disease, 10 have been genetically linked and most are associated with staff or customers at the California Grand Casino in Pacheco, Contra Costa Health (CCH) said in a news release late last week.

The agency has contacted more than 300 people who may have been exposed to active TB, officials said.

CCH indicated it has not identified a “current or ongoing source of transmission” at the Bay Area location but is working closely with management at the casino to test and screen all its staff.

“We are making this recommendation now because there is new evidence that TB may have spread among people who spent time at the casino from 2018 to 2023,” Dr. Meera Sreenivasan, deputy health officer for Contra Costa County, said in the release. She added that TB can live inside a person for years before even showing signs of its presence.

“That is why it’s important to take a test, even if you do not feel sick. TB can cause serious illness, but it is treatable and curable with medicine, especially when caught early,” Sreenivasan urged.

The agency, however, did not elaborate on how the cases were first identified, nor did officials offer further details.

In a statement, casino spokesperson Becky Warren said officials are committed to the safety of customers and employees.

“None of the currently linked cases involve our employees. They involve third parties service providers who were sometimes on site. Additionally, Contra Costa Health has not identified any ongoing sources of transmission at the card room. We are actively collaborating with the County on notifications and testing to uphold public health and safety,” the statement read.

According to data released earlier this year by the Centers for Disease Control and Prevention, TB cases reported in the country appeared to be nearing pre-pandemic levels. That may be because many diagnoses may have been missed, misdiagnosed or delayed during the pandemic.

TB is usually found in the lungs and can cause coughing, chest pain and fever – characterized by coughing up blood or mucus.

It can spread when someone has developed symptoms, coughs or breathes out bacteria, especially in an enclosed area for a long period of time.

The only way to know if someone was infected after an exposure is to test, and CCH encourages those who believe they may have been exposed to talk to their health care provider.

The disease is curable, often treated with a standardized course of drugs that usually includes antibacterial medicines, according to the World Health Organization. It can also be prevented with protocols including screening, vaccination and making sure people who are infected finish their course of treatment.

Each year, about 10 million people fall ill with TB and about 1.5 million people die. It is one of the leading causes of death for people with HIV worldwide, according to the CDC.

There has also been a global rise in tuberculosis.

CNN’s Jacqueline Howard contributed to this report.

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