Global TB infection rate levels off
For the first time in modern history, the rate of infections in the global tuberculosis epidemic has leveled off and might be on the “threshold of decline,” the World Health Organization announced Thursday.
The percentage of the world’s population struck by TB peaked in 2004 and then held steady or even declined in 2005, according to the report, but the actual number of new cases increased to 8.8 million because of the growing world population.
Dr. Mario Raviglione, director of the WHO’s Stop TB department, said the figures represented the first time ever that TB rates have declined. “Incidence has peaked around the world,” he said. “This is fruition of all our efforts.”
The announcement marks a milestone in the fight against TB, which was declared a global health emergency by the WHO in 1993 because of skyrocketing infections. Since then, the number of deaths has declined from more than 3 million to 1.6 million in 2005, according to the report.
The epidemic is centered primarily in Asia and sub-Saharan Africa, which accounted for 7.4 million new cases in 2005, or nearly 85 percent of the total.
“Nearly 60 percent of TB cases worldwide are detected and, out of those, the vast majority are cured,” U.N. Secretary-General Ban Ki-moon said in a prepared statement. “Over the past decade, 26 million patients have been placed on effective TB treatment.”
Despite the progress, Dr. Lee Reichman, executive director of the Global Tuberculosis Institute at the University of Medicine and Dentistry of New Jersey, cautioned that TB remains a wily opponent.
One of the major concerns is the emergence of “basically untreatable TB” – strains of the disease known as multi-drug resistant and extensively drug resistant TB.
Experts fear that either or both of those strains could get a stronger foothold, reversing the current successes in treatment. Treatment of drug-resistant strains of TB costs nearly twice as much as treating conventional TB and takes much longer.
Tuberculosis, once called “consumption” because of the way people wasted away, is one of the oldest diseases known to man. It is an often-lethal infection of the lungs characterized by fever, weight loss, night sweats and coughing up blood.
Saturday, World Tuberculosis Day, marks the 125th anniversary of German bacteriologist Robert Koch’s discovery of Mycobacterium tuberculosis, the microorganism that causes TB.
Unlike most common infections, tuberculosis is difficult to cure. Treatment of an active infection usually entails taking four antibiotics for two months, then two antibiotics for another four months. In the past, patients often stopped taking their drugs after a few weeks, leading to a recurrence.
Incomplete treatment is the primary source of drug-resistant TB. The report noted that the incidence in 2005 of these hard-to-cure strains was not as high as was expected. But it attributed that apparent good news to poor detection of the strains in developing countries.