WHO: Drug-Resistant TB Diagnoses Are Rising; Vast Number of Cases Still Go Undetected

WHO: Drug-Resistant TB Diagnoses Are Rising

Vast Number of Cases Still Go Undetected

BETSY MCKAY

Updated Oct. 23, 2013 2:34 p.m. ET

Drug-resistant tuberculosis has become a public health crisis, the World Health Organization declared Wednesday, with the number of people diagnosed with the deadly airborne disease rising so fast that some countries don’t have enough drugs or medical staff to treat them all. And the vast majority—around four-fifths—of drug-resistant TB cases are still going undetected, the United Nations public health agency said in its latest annual report on TB, calling targets for diagnosing and treating the disease “far off-track.”Overall, about a third of cases of all forms of tuberculosis—about 2.9 million illnesses—were undiagnosed or unreported in 2012, the agency said.

New, rapid molecular tests are helping doctors and public-health authorities diagnose drug-resistant TB more widely and effectively than ever before, producing a sharp rise in the number of cases in 2012, the WHO reported. But the surge is overwhelming some countries that didn’t stock enough drugs, it said, calling on countries using the new tests to make sure they have enough medications and trained medical cadres to manage the complicated, lengthy and painful treatment of drug-resistant patients.

“This is a public health crisis,” said Mario Raviglione, director of the WHO’s global TB program. “You cannot afford to make a diagnosis and not be able to treat patients. We consider that an ethical issue.”

The WHO estimates that about 450,000 people contracted MDR-TB in 2012, and others believe the disease is even more widespread, citing recent regional studies that have found levels of TB or drug-resistant TB that are far above what authorities originally believed.

But only a portion are diagnosed: 94,000 new cases of drug-resistant and multidrug-resistant tuberculosis were diagnosed in 2012, up from 62,000 diagnosed cases in 2011, the WHO said.

Of that new total, 77,000 were put on antibiotic regimens in 2012. The remaining roughly 17,000 were in waiting lines for treatment, Dr. Raviglione said. The waiting lines may be growing this year, other TB experts said, as more diagnostic tests are used.

Meanwhile, the number of people diagnosed with XDR-TB, a highly drug-resistant form of the disease with few treatment options, also rose sharply, to 2,230 cases in 2012, from 1,464 in 2011.

Some 88 countries have procured new molecular tests such as the Xpert MTB/RIF, which can diagnose tuberculosis and a common form of resistance in 100 minutes—the first major advance in tuberculosis diagnostics in more than a century. The WHO said about 3.2 million of the Xpert MTB/RIF tests, manufactured by Cepheid, CPHD -1.00% a U.S. company, had been procured by those countries as of June 2013. South Africa has adopted it as its primary diagnostic test for TB, the WHO said.

Waiting lists for drugs persist or are growing in numerous countries, and were particularly acute in South Africa, China and Pakistan in 2012, whose ratio between the number of patients diagnosed with MDR-TB and the number enrolled in treatment rose by more than 10%, the WHO said. In several African countries, only 51% of detected cases were enrolled in treatment in 2012, the agency said.

While a lack of drugs is problematic, so too is a shortage of medical staff trained to treat drug-resistant patients, who must take multiple drugs daily for as long as two years, said Lucica Ditiu, executive secretary of the Stop TB Partnership, a network of organizations involved in TB. “There are not enough people to give the drugs,” she said. “Who will do it? Who is available and trained?”

An estimated 8.6 million people contracted tuberculosis and 1.3 million died from it in 2012, including 320,000 people who were infected with HIV, the virus that causes AIDS and makes people more susceptible to TB infection. While the estimated number of new cases per year has been falling steadily for a decade, the annual rate of decline of about 2% a year is too slow, the WHO said. Millions of cases have gone undiagnosed every year. In 2012, 31% of missed cases were in India, Dr. Raviglione said.

“This disease should be a disease of the past,” Ray Chambers, a U.N. special envoy for health financing, said. “We have to find those three million people and test and treat them,” he said of the undetected TB cases, calling for more trained community health workers in rural areas.