In-depth: TB - the year that was
HEALTH: One-hour TB test "must be affordable" for poor countries
Photo: David Gough/IRIN
TB patients waiting in a hospital. Ideally, the test should be simple enough to administer at basic health facilities
NAIROBI, 16 September 2010 (PlusNews) - A new one-hour test for tuberculosis will only have an impact in the global fight against the disease if it is made affordable to poor countries, experts say.
"If it comes out and costs a million dollars, then clearly it won't be feasible; it needs to be cheap enough for poor countries to use widely," said Mario Raviglione, director of the World Health Organization's Stop TB Department.
The one-hour test, developed by the UK's Health Protection Agency (HPA) follows the recent announcement of a two-hour "Xpert MTB/RIF test
" for TB.
According to the HPA, the rapid test, which uses DNA identification to diagnose TB, is more sensitive than other tests currently available. It is, however, unlikely to be available until trials – due to take place over the next year – are completed.
The most basic TB test in use takes about 24 hours to yield results, and more thorough confirmatory tests can take up to eight weeks.
Raviglione noted that it would be crucial for the test, once available, to be simple enough to use at basic health facilities.
"It needs to be simple enough to administer at the point of care, so that when someone walks in with a cough, they can be diagnosed and treatment can be started immediately," he noted. "It should be as simple as the HIV test."
Late diagnosis is one of the major hurdles to global TB programmes; early diagnosis would help to cut transmission levels. "Not only are we not diagnosing about one-third of TB patients globally, but many of those who are diagnosed are caught at a late stage, which has implications for health systems and also for public health, because these people are walking around, unknowingly spreading the disease," Raviglione said.
According to Joseph Sitienei, head of Kenya's National TB and Leprosy Control Programme, faster diagnosis is long overdue.
"We have been using a 125-year-old system – the sputum test – so it is about time we had something more efficient," Sitienei said. "At the moment, patients have to go away and come back for results the next day or may have to wait several weeks for confirmation; some patients never return to get results or start treatment."
|We have been using a 125-year-old system - the sputum test - so it is about time we had something more efficient
Sitienei noted that if the test became widely available and resulted in more diagnoses, more funds would be needed. "This will need extra resources, extra health workers, more training and so on," he said.
"TB is one of the cheapest diseases to treat, and there should be no excuse not to expand services," WHO's Raviglione said. "We must find a way to cover the additional costs of care."
It costs between US$20 and $25 to treat one TB patient using the WHO-recommended "directly observed treatment short course", DOTS.
Globally, an estimated 440,000 TB cases are diagnosed annually. TB is the biggest killer of HIV-infected people in Africa. According to the WHO's 2009 Global TB Control Report
, about 1.37 million new cases of tuberculosis occurred among HIV-infected people in 2007.