ANNAPOLIS – Tuberculosis is the world’s deadliest disease killing almost 3 million people a year, but many Americans think it is a thing of the past, say health officials.
In Maryland, particularly in Montgomery County where there are many new immigrants, doctors must continually be watchful of an increase in cases, or Baltimore’s return to the top three metropolitan areas for the disease in the country.
Nearly 2 billion people – almost a third of the world population – have the bacterial infection, according to the National Institutes of Health.
The United States contains less than 1 percent of those cases, yet it poses a real threat because the disease is airborne, is more prevalent in populations with high immigration rates and spreads among those with the HIV virus, said Toni Gervasio, a nurse and infection control practitioner at Mercy Medical Center in Baltimore.
“Immigrants come in and we can’t stop (and test) them,” said Gervasio. “That’s how a lot of infectious diseases come in. People travel and the world is a lot smaller.”
Baltimore consistently ranked among the top three major U.S. cities in the incidence of tuberculosis beginning in 1965. But in 1978, the city initiated directly observed therapy, in which public health nurses watch tuberculosis patients take their medication.
The strategy is responsible for dropping the city’s ranking to 40th last year. In the past decade, Baltimore has cut its cases by almost half — from 122 in 1990 to 67 last year.
“Even though our numbers are dropping we’re not cutting our tuberculosis programs at all,” said Dr. Peter Beilenson, Baltimore commissioner of health. “We’re not letting down our guard.”
Overall, the number of active tuberculosis cases in Maryland has steadily declined with 384 in 1990 compared to 283 last year. However, the disease is increasing among the foreign-born.
That’s what’s been fueling the increase in cases in Montgomery County, which had the most tuberculosis cases in the state last year with 83, about 30 percent of the total.
“We’re seeing a shift in the kinds of patients that develop tuberculosis, especially in Montgomery County, where 95 percent of the cases have been occurring in immigrants and students from overseas,” said Dr. Thomas Walsh, medical director of the Tuberculosis Control Program for Montgomery County Health and Human Services.
The Washington Post reported Wednesday that 1 of every 6 Washington region residents is an immigrant, up from 1 in 22 in 1970.
Although tuberculosis peaked in the U.S. in the early 1900s, it had almost disappeared in the 1970s and early 80s when immigration to the U.S. began to slow. That caused many health departments to cut back on their tuberculosis programs.
Then in 1985, with the HIV epidemic and a surge of immigrants coming from areas with high tuberculosis rates, U.S. cases increased. A similar worldwide increase triggered a 1992 declaration by the World Health Organization that tuberculosis was a “fire raging out of control” in developing nations.
In Baltimore and Prince George’s County, tuberculosis patients have a different face. They are typically low-income minorities.
African-Americans represented 46 percent of last year’s tuberculosis cases, but only 28 percent of the population. Hispanics made up 11.6 percent of the cases and 4.3 percent of the state’s population. Another 22.2 percent of tuberculosis cases in Maryland were among Asians, who are only 4 percent of the state population.
“Tuberculosis, like many other health conditions, adversely impacts the poor — people who have less-than-optimal access to health care,” said Art Thacher, a health officer with the Prince George’s County Health Department.
Symptoms of tuberculosis include a bad, persistent cough, chest pains and coughing up blood. If left untreated, it has a 40 to 60 percent chance of death, but if properly treated, there’s a cure rate of more than 90 percent. However, outbreaks of drug-resistant strains may change that.
Local health departments and physicians use a tuberculin skin test to diagnose tuberculosis. If the test comes back positive, the patient is given a chest X-ray.
Most people who test positive don’t get active tuberculosis, but the bacteria can multiply and develop into active disease in people with weakened immune systems, such as those with HIV. Only people with active tuberculosis can spread the infection. Immunization is not effective.
Health officials are quick to dismiss suggestions of a possible tuberculosis outbreak in America, but they emphasize continuous management and testing to make sure it doesn’t become rampant.
“We can’t say the problem is solved, and we can’t relax about it,” said Nancy Baruch director of the Division of Tuberculosis Control at the Maryland Department of Health and Mental Hygiene. “The real key is getting good tuberculosis control measures established overseas.
“Once you start doing that, you’ll see the cases drop. Every less case overseas, is eventually going to turn into less cases here.”