The number of people falling ill each year with tuberculosis (TB) is falling, with 8.8 million global cases last year compared to 9 million in 2005, and the number of deaths to the disease in 2010 fell to the lowest level in a decade. However, lack of funding, especially in fighting drug-resistant forms of TB, could undermine this progress, said the World Health Organization in a report that was published online yesterday.

Since 1997, WHO, the directing and coordinating authority for health within the United Nations, has published a comprehensive annual report on the worldwide TB situation. The report accounts for over 99% of the world’s TB cases, giving an up-to-date assessment of the TB epidemic and how much progress is being made in prevention, care and control at global, regional and country level, including data from 198 countries.

The latest Global tuberculosis control 2011 report, the sixteenth, finds that while cases are falling and global deaths to TB are at their lowest for a decade, this progress is at risk from underfunding, especially efforts to combat drug-resistant forms of TB.

It shows that:

  • The number of people worldwide falling ill with TB dropped to 8.8 million in 2010, after peaking at 9 million in 2005.
  • Deaths from TB fell to 1.4 million in 2010, from a peak of 1.8 million in 2003.
  • Between 1990 and 2010, deaths to TB have fallen 40%, and all regions, apart from Africa, look set to achieve a 50% drop in deaths by 2015.
  • 87% of TB patients treated in 2009 were cured, bringing the total of successfully treated cases since 1995 to 46 million, with 7 million lives saved.
  • Much of the progress is the result of expanded efforts in large countries.
  • But, given that a third of estimated global TB cases aren’t reported, it is unclear how many go undiagnosed and do not receive the proper treatment.
  • Across the globe, the share of money allocated to fighting TB in 2012 has risen to 86%.
  • However, most low income nations are still heavily dependent on external funding.
  • There are some promising developments in the diagnosis of TB and new drugs and vaccines, including shorter treatments.
  • Phase III trials are expected to report results during 2012-2013, and two Phase II trials for new MDR-TB drugs are due to report results in 2012.
  • Overall, there is a total funding gap of 1 billion US dollars for TB implementation in 2012; with $200 million of the shortfall being for multidrug-resistant TB.

The report shows “major progress”, but it is “no cause for complacency,” United Nations Secretary-General Ban Ki-moon told the press.

“Too many millions still develop TB each year, and too many die.” He urged nations to give “serious and sustained support for TB prevention and care, especially for the world’s poorest and most vulnerable people.”

WHO Director-General, Dr Margaret Chan said strong leadership and domestic financing, with robust donor support is starting to make a real difference in many countries.

“The challenge now is to build on that commitment, to increase the global effort – and to pay particular attention to the growing threat of multidrug-resistant TB,” she added.

Among the countries making progress against TB are Kenya and the United Republic of Tanzania, both in Africa. In these countries, TB cases and deaths have been falling steadily over the last ten years, after a peak linked to the HIV epidemic.

People infected with HIV who are also infected with the bacteria that cause TB are up to 34 times more likely to develop TB. The report shows that in 2010:

  • The proportion of worldwide TB patients who were also infected with HIV was 12%.
  • 1.1 million people living with HIV developed TB, with 82% (900,000) of these being in Africa.
  • Testing for co-infection HIV has risen to 59% of TB patients in Africa.
  • But current commitment is not enough if the region is to meet its 2015 TB targets.
  • In 2010, nearly half of TB patients in Africa who tested positive for HIV were taking antiretrovirals, and around 75% began co-trimoxazole preventive therapy, which helps reduce deaths (both drugs are essential for treating TB/HIV coinfection).

Brazil has also reported significant progress against TB in the last decade.

And a WHO statement describes China’s progress as “dramatic”. Over the last decade TB prevalence in China has halved, from 215 to 108 per 100,000 people, and deaths to TB fell by nearly 80% from 216,000 in 1990 to 55,000 in 2010.

A significant threat for the future, however, appears to be multidrug-resistant TB (MDR-TB), the most underfunded area of TB implementation, according to the report.

MDR-TB bacteria are resistant to the most powerful first line anti-TB drugs isoniazid (INH) and rifampicin (RMP). Cases of MDR-TB do not respond to the standard six month treatment with these drugs and can take two years or more to treat with less potent, more toxic and considerably costlier drugs.

The report shows that while the number of people infected with MDR-TB who were successfully treated went up to 46,000 in 2010, this represents only 16% of the estimated number of MDR-TB patients that needed the treatment.

Dr Mario Raviglione, Director of WHO’s Stop TB Department said that a new quick test for MDR-TB was “revolutionizing TB diagnosis”. Six months after WHO gave the test its seal of approval, 26 countries were already using it, and ten more are expected to have it by the end of this year, said Raviglione:

“But the promise of testing more people must be matched with the commitment to treat all detected. It would be a scandal to leave diagnosed patients without treatment,” he urged.

Written by Catharine Paddock PhD