One out of four tuberculosis (TB) deaths is HIV-related, twice as many as previously recognised, despite a rise in testing for TB in places like Africa, where the disease is most prevalent according to the World Health Organisation’s (WHO) 2009 global tuberculosis control report.

There were an estimated 1.37 million new cases of TB among HIV-infected people in the world and 456,000 deaths in 2007.

The findings highlight the urgent need to find, prevent and treat TB in people living with both infectious diseases, according to WHO director-general Dr Margaret Chan.

“Countries can only do that through stronger collaborative programmes and stronger health systems that address both diseases,” she said.

WHO also found the original estimates for TB-related deaths may have been underestimated in the past but the report shows that the total number of TB cases remained stable in 2007. The percentage of TB incidence globally has continued the slow decline that was first observed in 2004.

TB incidence is the highest in Africa but that rate has been falling since its peak in 2005. The only region where TB has continuously risen is Europe, specifically in the poorer countries of the former Soviet Union.

According to the report there was a total of 9.3 million cases of tuberculosis in 2007 – 55% in Asia and 31% in Africa.