Health experts see a glimmer of hope in the fight against tuberculosis (TB) for the first time since the disease’s spread was declared a global emergency more than a decade ago.
But although global TB rates are levelling off, the emergence of drug-resistant versions of the disease — combined with the Aids pandemic — is complicating control efforts.
A new report issued on Thursday by the World Health Organisation (WHO) found that the rate of TB — the number of infections per 100 000 people — levelled off in 2005, the last year for which comprehensive data is available. The report was released ahead of World TB Day on Saturday.
”This is a breakthrough,” said Dr Marcos Espinal, executive secretary of the WHO’s Stop TB Partnership. ”It’s the first time we’ve had good news about the epidemic since 1993.”
Worldwide, the rate of TB has stabilised at less than 150 cases per 100 000 people — although in Africa, it is more than double, at nearly 350 cases per 100 000 people.
But while the global rate remained relatively steady, the actual number of people with TB increased, due to the growth of the world’s population. In 2005, there were 8,8-million new TB cases and 1,6-million deaths, the WHO said.
Deadly strain
The emergence of a deadly version of the disease, known as extensively drug-resistant tuberculosis (XDR-TB), has also complicated efforts to control the illness.
XDR-TB is resistant to most drugs commonly used to treat TB, and health experts are concerned that Africa’s high rates of HIV/Aids infection — which weakens people’s immune systems — will propel its spread.
The drug-resistant disease has also appeared in wealthy countries, with cases reported in all Group of Eight industrialised nations.
In Africa, the disease has only been reported in South Africa — which has detected more than 300 cases, with about 30 new cases every month. But experts said they suspect it is present — but undetected — in other African countries with weaker surveillance systems.
However, lack of access to existing treatments are a bigger killer worldwide than drug-resistant strains, experts said.
”Most people have tuberculosis that is sensitive to the drugs we use, but will die because of the failure to access the very simple, cheap treatment that we’ve been using for the last 40 years,” said Dr Tom Ellman, a health adviser for the medical aid group Médecins sans Frontières.
Another problem is antiquated means of diagnosing and treating the disease.
”Progress in tuberculosis research reads like a history book,” said Dr Dermot Maher, a WHO disease expert. The last effective tuberculosis drug was discovered more than 50 years ago, and takes about six months before patients begin to get better.
The standard procedure for diagnosing TB — a century-old test where lab technicians search for the bacteria under a microscope — misses up to half of all active infections.
Determining whether the strain is drug-resistant can take up to two months — and if the patient also has Aids, he or she could be dead by the time the results are in.
TB control
Although TB research has recently been boosted by public-private partnerships and donors such as the Bill and Melinda Gates Foundation, experts do not expect it will be years before new diagnostics or drugs are available.
To make a serious dent in TB control, health officials are now working to merge TB and Aids treatment programmes.
Of the 40-million people worldwide living with HIV/Aids, one-third are estimated to also have TB. But in much of Africa, patients must seek out treatment separately.
”HIV is fuelling the tuberculosis epidemic,” said Maher. ”If we can remove the fire from the flame, the tuberculosis incidence will go down.”
Still, it is unclear whether countries are taking the international health community’s advice. Médecins sans Frontières says that only 3% of TB patients in Africa are offered HIV tests.
”The question is how these wise words from WHO and others are translated in the field,” said Ellman. ”We are concerned that there has been very little effort to translate what should be happening in theory into practice.” — Sapa-AP