Tuberculosis not to be ignored as serious threat

Published July 7, 2006

With worldwide attention to bird flu and the summer threat of West Nile virus, attention may be drawn from insidious killers like tuberculosis. Globally, some 9-million will become sick with TB, and 2-million to 3-million will die this year. TB causes more deaths among women worldwide than all causes of maternal mortality combined. The immune-compromised are more vulnerable to TB disease, as are racial and ethnic minorities.

A recent publication from France's Pasteur Institute suggests that TB is much older than previously thought. Although the disease has plagued human populations since antiquity, an abstract from the Pasteur Institute suggests the disease dates back 3-million years. TB may be the world's oldest disease, predating the plague, typhoid fever or malaria.

Clothing design dealt with TB. During the Renaissance, European high-collar fashions were designed to cover swollen necks, and many ladies used white powder to emulate TB victims' chalkish color.

In 1882, Robert Koch developed a technique that allowed him to see the "TB bug" and triggered the fight against the world's deadliest disease. The TB preventive vaccine, BCG, became available in 1921. Unfortunately, the vaccine has varying degrees of effectiveness and is not recommended in the United States, except for certain high-risk persons. In 1944, anti-TB drugs were successfully used to combat the disease. Side effects plagued the initial drugs, but now newer TB regimens have reduced adverse effects.

With declining U.S. tuberculosis cases, the public health community predicted the end of TB by 2000. In the mid 1980s, public health resources were shifted to a new burgeoning public health threat: AIDS. Increasing HIV/AIDS cases added significantly to the risk of TB disease and the impact on compromised TB efforts proved devastating. Professional interest in TB declined, while dollars for screening and monitoring cases disappeared. County health departments struggled for resources to address local TB disease.

Tuberculosis reestablished its presence, and the dream of a TB-free society by the millennium evaporated. Mark Twain once said the reports of his demise were greatly exaggerated. True, also, for the predicted demise of tuberculosis. Case numbers then climbed in the United States, and though TB is on the decline again, cases peaked at 26,673 in 1992. The U.S. government recommitted attention to the more devastating strain of multidrug-resistant tuberculosis, and cases were again on the wane. There were 14,517 U.S. cases in 2004, with predictions of further declines. U.S. health officials can expect 14,000 new cases this year. Tuberculosis remains a major problem, particularly among immigrant populations.

In 2003, foreign-born individuals accounted for 53 percent of all TB cases diagnosed in the United States, as compared with 29 percent of all cases in 1993. Whether U.S.- or foreign-born, 82 percent of all TB cases involve racial and ethnic minorities. African-Americans represent 28 percent of cases; Hispanics, 29 percent; Asians, 23 percent; Caucasians, 18 percent; and American Indians, Alaska Native and Pacific Islanders, 2 percent.

Florida trails California, New York and Texas in the numbers of new TB cases. Florida's high numbers reflect increasing immigration from TB-affected countries. Fortunately, improved surveillance allows us to find and treat the disease. Such vigilance must continue to protect the trend of declining cases in the Sunshine State.

There are an estimated 9-million to 14-million persons in the United States with infection from M. tuberculosis. It is important to understand that infection is not disease. However, 10 percent of infected individuals may go on to develop illness. Multidrug-resistant TB is on the rise. One estimate set the cost of a single case at nearly $1.3 million.

Finishing the job to eliminate TB requires the commitment to eradication. Multidrug resistance represents a challenge to the pharmaceutical companies to develop new and effective drugs. Newer antibiotics are critical to the continued fight against TB and other emerging diseases.

An individual's risk for disease is low, and aggressive efforts to find and treat TB patients protect the community at large. The transmission of TB requires sustained exposure over long periods of time. A person living with someone with the disease untreated is at a high risk. Medical personnel and those working in nursing homes and hospitals should be periodically tested. At-risk populations should have access to screening. Health departments provide medication and "drug observed therapy" to those infected or diseased. Casual contact with a sick person with TB presents little or no risk.

Should you have questions about TB, call the local health department.

Dr. Marc J. Yacht is director of the Pasco County Health Department.