Coinfection of tuberculosis and HIV poses global threat

"Today, tuberculosis is one of the top 10 leading causes of death globally, causing more than 4000 deaths every day," the UN secretary general, Ban Ki-moon, told the meeting. "This is shocking: no one should die of tuberculosis, a preventable and curable disease, in this prosperous and technology rich 21st century."

"Despite the fact that HIV and tuberculosis frequently occur in the same person, we continue to deal with the two diseases separately," Mr Ban said. "Fewer than one third of all people living with HIV and tuberculosis worldwide received appropriate treatment for both diseases in 2007."

He called for "more collaboration between sectors, better coordination between actors, greater investment in tuberculosis research and control, and strengthened health systems" to tackle the problem.

Tuberculosis accounts for an estimated 250 000 deaths a year among people with HIV and is the primary cause of death among people with HIV in Africa. Because HIV weakens the immune system, people with the virus are up to 50 times more likely to develop tuberculosis than people who are HIV negative. Without proper treatment with tuberculosis drugs, most people with HIV die within two to three months of becoming sick with tuberculosis.

The meeting heard that the "outdated" drugs, diagnostics, and vaccines available are not appropriate for people with HIV and tuberculosis coinfection and so new tools are needed that work in the presence of both diseases.

Kevin Decock, director of the World Health Organization's HIV department, told the BMJ that the coinfection increasingly poses a threat to the HIV negative population as well, particularly as resistant and extensively resistant strains of tuberculosis become more widespread.

Dr Decock warned that the people most at risk were health workers, followed by international travellers, but the general population could also be exposed to resistant strains if they became more common. In parts of the former Soviet Union one in five patients with tuberculosis in the general population has a resistant strain.

He said that if multidrug resistant tuberculosis merged with the HIV pandemic "the consequences could be disastrous." He was concerned that this could lead to a shift in the treatment of HIV patients: "It's one thing asking health workers to care for patients when the only danger is direct exposure to blood but quite another thing if they risk developing a potentially incurable disease that is infectious simply through inhalation."