Drug-resistant TB coming to U.S. from abroad-study

Immigrants may be steadily bringing new cases of drug-resistant tuberculosis into the United States, hampering efforts to eradicate the deadly infection, researchers said on Tuesday.

The report, published in a special issue of the Journal of the American Medical Association focusing on TB, showed the need for global control of the ancient disease, the researchers said.The World Health Organization estimates 2 billion people, or a third of the world’s population, have tuberculosis. The disease, which has troubled humankind for thousands of years, kills 2 million people a year.The AIDS epidemic has fueled a resurgence of TB, which is especially deadly to those with immune systems weakened by HIV. Efforts to treat TB have resulted in mutated forms called drug-resistant TB, which results when patients do not complete months of treatment with a cocktail of antibiotics.Dr. Reuben Granich of the Centers for Disease Control and Prevention told a news conference that while TB fell overall by 33 percent in California between 1994 and 2003, the proportion of cases that resisted more than two drugs, called multidrug-resistant or MDR TB, remained steady.His team studied all reported cases of tuberculosis on California, the state with the most cases of TB in the United States.They looked at the more than 38,000 cases reported across the state over that time, especially the 28,700 tested for resistance to the two mainstay drugs, isoniazid and rifampin.Of the 28,700 cases, 1.4 percent were resistant to the drugs, meaning a different cocktail would be needed to treat those patients.That percentage stayed steady over the 10-year period. IMPORTING DISEASEGranich also found that 83 percent of the MDR cases were in foreign-born people, who came from 30 different countries.”We didn’t find multidrug-resistant TB was associated with homelessness or using injected drugs or HIV/AIDS or being incarcerated,” Granich told a news conference.Cases were spread across the state, meaning a big expense for some clinics that may not be set up to absorb the costs, or for insurers.Treating a single case of MDR TB can cost anywhere between $28,217 and $1.2 million.Only 67 percent of those in the study completed the 18 to 24 months of drug cocktail therapy needed to cure them. Fourteen percent died and 14 percent moved before they could finish — meaning they could spread their drug-resistant infections to others.”We need to ensure strong TB programs,” Granich said.Many of the immigrants had been vaccinated. The widely used BCG vaccine helps protect infants and young children against the deadliest effects of tuberculosis, but does not prevent infection and does little for adults.”We desperately need a new vaccine to protect adults against pulmonary disease,” said Chris Dye of the World Health Organization.In the meantime, there may be cheap ways to prevent infection in the developing world, said Dr. Alison Grant of the London School of Hygiene and Tropical Medicine in London.Her team gave the antibiotic isoniazid to HIV-infected gold miners in South Africa and found it prevented up to 42 percent of new tuberculosis infections.”WHO recommends using isoniazid in HIV-positive patients but it is not widely done,” Grant told the news conference.She said her real-world study showed it could work. (Source: Reuters Health, June 2005)