King County Public Health marks World TB Day with cautious note about the disease

Public Health – Seattle & King County recognized World Tuberculosis Day, March 24, by releasing new information about the disease in King County, including the wider spread of a concerning strain of the tuberculosis bacteria.

Public health officials recently discovered that the strain of TB, called PCR0001, which is responsible for 76 cases in the local homeless population since 2002, is now being transmitted among the broader community as well. This development is concerning because the strain appears more likely to infect others and cause active TB disease than the more commonly seen strains. Of the 116 active TB cases diagnosed in King County in 2010, six were caused by the PCR0001 strain, including three outside the homeless population.

“We aren’t immune in King County from the global epidemic or the changing nature of the disease itself,” said Dr. David Fleming, director and health officer for Public Health – Seattle & King County. “The wider spread of what appears to be a more potent strain is concerning, and it’s an important example of why we can’t afford to relax our efforts in controlling TB.”

The TB Control Program has made focused efforts in recent years that have helped to control the spread of the PCR0001 strain among the homeless population, and is now prioritizing its work on controlling the spread of the strain more broadly.

Approximately one third of the world’s population is infected with tuberculosis (TB), and two million people die from it every year. King County’s active TB rate is consistently among the highest for any local area in the country, reflecting the global nature of King County’s community. Of the 116 people diagnosed with active TB in 2010, 84 percent were born outside the United States.

Public Health – Seattle & King County’s TB Control program ensures that people with active, or infectious, TB are diagnosed and treated until cured. They also evaluate and treat, if appropriate, people exposed to infectious TB, so it does not continue to spread.  Everyday, TB program staff ensure that infectious TB patients adhere to drug treatment, which consists of multiple medications for six months or longer. More than 2,800 clients make almost 12,000 visits to the TB clinic annually for treatment. The TB Control Program also evaluates immigrants and refugees who are suspected of having active TB.

However, because of state and King County budget crises, the TB Control Program faces continued funding challenges. Over the past several years, the TB Program has reduced staff and now limits services to the highest priority cases and contacts.

“We estimate approximately 100,000 people in King County have latent, or dormant, TB infection. While they aren’t contagious now, some will develop active TB in the future and could infect others,” said Dr. Masa Narita, TB Control Officer for Public Health. “TB is curable and preventable, but controlling TB is an ongoing challenge, especially with fewer resources to protect the community.”

Highlights of 2010 TB data:

• 116 people were reported with active TB, for a rate of 6 per 100,000 people, a decrease from 130 cases in 2009. This was noticeably higher than the U.S. rate of 3.8 cases per 100,000 people.
• 84 percent of infected individuals were born outside of the United States. Of these individuals, 67 (62 percent) came from five countries: the Philippines, Somalia, Ethiopia, Vietnam and India
• People of color continue to have disproportionately high rates of TB, with the highest case rate among individuals who identify their race as black (26.4 cases per 100,000) or Asian (21.4 per 100,000).
• 20 people (17 percent) treated for active TB were resistant to at least one TB medication.
• Two multi-drug resistant TB (MDR-TB) cases were diagnosed in King County in 2010. Multi-drug resistant cases are much more expensive to treat, costing up to $250,000 each.

Background on TB

Tuberculosis, also called TB, is an infectious disease caused by a bacterium named Mycobacterium tuberculosis. TB often involves the lungs (pulmonary TB) but can infect almost any organ in the body. TB is almost always curable with antibiotics that are readily available in countries such as the United States.

People with active TB disease are made sick by bacteria that are active in their body. People with inactive, or latent, TB infection are not sick because the germ is inactive inside their body, and they cannot spread TB infection to others.

To view the 2010 summary data and for more information on Public Health’s TB Control Program and activities, visit: www.kingcounty.gov/health/tb.

Providing effective and innovative health and disease prevention services for over 1.9 million residents and visitors of King County, Public Health – Seattle & King County works for safer and healthier communities for everyone, every day.