Tuberculosis (TB) kills. In 2007 there were an estimated 9.27 million new TB cases worldwide and about 1.78 million people died from the disease in the same year. Sputum smear microscopy remains the primary tool for TB diagnosis in most countries, but only an estimated 44% of TB cases are smear positive [1]. Though culture of TB bacteria is more sensitive, it may take several weeks to diagnosis due to low growth rates. Research is ongoing to develop the best diagnostic strategy for smear-negative cases (still 5.2 million people after all), with 'best' in this context implying highly sensitive, specific, fast, reliable and, last but not least, cost effective.
展开▼
