FRIDAY, April 5, 2002 (HealthDayNews) -- The number of tuberculosis cases in the United States fell for the ninth year in a row in 2001, and federal health officials say they may ease guidelines that recommend annual skin tests for health-care workers in all states.
However, experts warn the deadly lung disease remains a killer in this country. More troubling, they say, is the fact that it's a bigger problem in foreign countries, whose immigrants make up the largest group of victims here.
"There are populations that have a much higher risk," says Dr. Renee Ridzon, a medical epidemiologist with the National Center for HIV, STD and TB Prevention, part of the Centers for Disease Control and Prevention (CDC).
Currently, the CDC recommends health-care workers have tuberculosis skin tests every year to check for exposure to the disease, although the guidelines are not mandatory. The workers have their skin scraped, and they return in two or three days to see whether bumps have appeared on the skin.
Depending on their size, the bumps may be a sign that "this body has seen the germ that causes tuberculosis," Ridzon says.
Further tests, including chest X-rays, determine if infection has set in. Only 5 percent to 10 percent of people exposed to the disease will come down with it.
Some states have such a low prevalence of tuberculosis that tests of health-care workers may "not be worth doing," Ridzon says.
Wyoming and North Dakota, for example, typically report fewer than 10 cases a year, she says. When the rate is so low, the skin tests may actually turn up more false positives than actual cases.
"This is the same reason we don't recommend testing school children," she says. "American-born school children have a very low risk of having tuberculosis. All you were seeing were false positive tests."
Tuberculosis is only spread through the air and is a risk in hospitals, both for patients and health-care workers. While it is contagious, most people have strong immune systems that can fight off infection and subsequent disease if it appears.
The federal guidelines were written in the early 1990s, after tuberculosis rates had gone up for several years in a row.
"Now that we've had this return to this steady decline, we're saying it's time to redo the guidelines," Ridzon says.
According to the CDC, 15,991 people were infected with tuberculosis in 2001, a drop of 2 percent from 2000. At a press conference in March, federal officials said they were happy about the falling rate, but concerned it was not as big a drop as it was from 1992-2000, when rates fell by an average of 7 percent a year.
About half of all tuberculosis cases in the United States are among people who were born in other countries, especially Mexico, the Philippines, Vietnam and India.
Dr. Lee B. Reichman, executive director of the New Jersey Medical School National Tuberculosis Center, says it makes sense to ease the health-care worker guidelines, but he adds the government must continue to make tuberculosis prevention a priority.
If politicians stop worrying about tuberculosis because of low infection rates, the disease may make a comeback as it did in the 1980s, says Reichman, author of Timebomb: The Global Epidemic of Multi-Drug Resistant Tuberculosis.
What To Do: For more information on preventing, detecting and treating tuberculosis, visit the CDC's Division of Tuberculosis Elimination. The American Lung Association also has answers to your questions about the disease.
