Let sunshine in to fight tuberculosis, WHO says

By Laura MacInnis

GENEVA (Reuters) - Ventilation and some sunshine could go a long way to reduce tuberculosis risks in hospitals and prisons, two strongholds of the contagious lung disease, the World Health Organization said.

In its latest Global Tuberculosis Control report, released on Tuesday, the United Nations agency also doubled its estimate of how many HIV-infected people catch and die from tuberculosis, and warned especially deadly strains are continuing to spread in all corners of the world.

Mario Raviglione, director of the WHO's Stop TB department, said that because tuberculosis bacteria thrive in stagnant air, "simply opening the doors" can reduce the chances that patients, inmates and others will become infected with the disease that killed about 1.8 million people in 2007.

That global tuberculosis death toll includes 1.3 million HIV-negative people and 456,000 who were also infected with the AIDS virus, deaths from which are strictly classified in health statistics as HIV fatalities.

"You can only die once," explained Kevin De Cock, the WHO's HIV/AIDS Director, who estimated HIV patients whose immunity levels are weak are more than 20 times more likely to catch tuberculosis than the rest of the population.

BETTER DATA

The WHO's large revision of the number of people with both HIV and tuberculosis reflected "better analyses, better data, and better methodology" and not a real increase in the twin infections between 2006 and 2007, De Cock told a Geneva news briefing.

HIV patients should be screened for tuberculosis and given drugs to reduce their risks of developing the disease, which can be caught by breathing in air droplets from a cough or sneeze of an infected person, the Belgian infectious-disease expert said.

About a third of the world's population is infected with the bacterium that causes tuberculosis, but only a small percentage of people develop the disease, which normally arises when immune levels are weakened due to pregnancy or illness.

The global prevalence of tuberculosis was nearly stable in 2007, with 9.27 million new cases reported compared to 9.24 million in 2006.

Although antibiotics can cure tuberculosis, drug-resistant strains of the disease have proliferated in recent years as a result of medical errors and the failure of patients to take the full six- to nine-month drug treatment course.

The WHO said that about 500,000 people worldwide have been diagnosed with multi-drug-resistant strains of tuberculosis, which cannot be treated with two or more front-line drugs.

And 55 countries and territories worldwide have reported at least one case of "extensively drug-resistant" tuberculosis or XDR-TB, which is virtually untreatable with today's medicines, according to the WHO study.

The actual prevalence of that lethal strain is probably even higher, as few poor countries are currently doing the series of tests required to evaluate the extent of drug resistance in their patients, Raviglione told the Geneva briefing.

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