SciDev.Net

[SYDNEY] Experts have warned of an impending catastrophe if critical gaps in the research and management of HIV/AIDS and tuberculosis are not urgently closed.

Tuberculosis (TB) kills about two million people every year, and is the leading cause of death in people with AIDS.

Today (24 July), at an international conference on HIV in Sydney, Australia, experts said poor countries are bearing the brunt of the twin epidemics. 

TB cases have been rising in sub-Saharan Africa since 1990, said Stephen Lawn, a researcher from the University of Cape Town, South Africa.

The areas worst hit by both infections are southern and eastern Africa, he said, where half of all people newly diagnosed with TB already have HIV.

Lawn says studies in Botswana show the current WHO-approved TB treatment strategy called DOTS (Direct Observation and Treatment – Short Course) has not reduced TB in HIV-infected people. "DOTS alone does not work," he said.

And both epidemics are being made worse by the emergence of extremely drug-resistant TB. Gerard Friedland, director of the AIDS Care Programme at Yale University, said that in areas with high rates of TB and HIV infection, drug-resistant TB threatens the success of both the World Health Organization's (WHO) Stop TB initiative, and HIV programmes rolling out antiretroviral drugs.

Speakers at the sessions highlighted areas critically in need of research, including measuring more accurately the burden and impact of TB in HIV-infected people.

A 2006 survey by the WHO found that most countries facing an HIV epidemic are not reporting the increase in TB cases, and that HIV-infected people are not benefiting from access to TB screening and subsequent treatment services.

Research into finding new diagnostic, screening and intervention tools is also needed. Doctors in most parts of the world are using a diagnostic test that is over a century old, and whose sensitivity in patients with both TB and HIV infections is just 20 per cent. This is "wholly inadequate", says Lawn.

Research is also needed to find out what anti-HIV treatment regime is most suitable for people infected with TB. Likewise, information on how best to treat TB infection in people with HIV is lacking.