Recent intensive efforts to improve collection and reporting of data on tuberculosis (TB) are shedding new light on the epidemic, revealing that there are almost half a million more cases of the disease than previously estimated. The World Health Organization (WHO)’s "Global Tuberculosis Report 2014," published today, shows that 9 million people developed TB in 2013, and 1.5 million died, including 360 000 people who were HIV positive.
The report stresses, however, that the mortality rate from TB is still falling and has dropped by 45 percent since 1990, while the number of people developing the disease is declining by an average 1.5 percent a year. An estimated 37 million lives have been saved through effective diagnosis and treatment of TB since 2000.
“Following a concerted effort by countries, by WHO and by multiple partners, investment in national surveys and routine surveillance efforts has substantially increased. This is providing us with much more and better data, bringing us closer and closer to understanding the true burden of tuberculosis,” says Dr. Mario Raviglione, director of the Global TB Program for WHO.
Although higher, these revised figures fall within the upper limit of previous WHO estimates. The report, however, underlines that a staggering number of lives are being lost to a curable disease and confirms that TB is the second biggest killer disease from a single infectious agent. In addition, around 3 million people who fall ill from TB are still being ‘missed’ by health systems each year either because they are not diagnosed, or because they are diagnosed but not reported.
Insufficient funding is hampering efforts to combat the global epidemic. An estimated $8 billion is needed each year for a full response, but there is currently an annual shortfall of $2 billion, which must be addressed.
The multidrug-resistant TB (MDR-TB) crisis continues, with an estimated 480 000 new cases in 2013. Worldwide, about 3.5 percent of all people who developed TB in 2013 had this form of the disease, which is much harder to treat and has significantly poorer cure rates. While the estimated percentage of new TB cases that have MDR-TB globally remains unchanged, there are severe epidemics in some regions, particularly in Eastern Europe and Central Asia. In many settings around the world, the treatment success rate is alarmingly low. Furthermore, extensively drug-resistant TB (XDR-TB), which is even more expensive and difficult to treat than MDR-TB, has now been reported in 100 countries.
Since 2009, with more laboratories rolling out rapid tests, there has been a tripling of MDR-TB cases being diagnosed. In 2013, 136 000 MDR-TB cases were detected and 97 000 people were started on treatment. Although the number of patients treated has increased three-fold since 2009, at least 39 000 patients, diagnosed with this form of TB, were not being treated last year and globally only 48% of patients were cured.
“The progress that has been made in combatting MDR-TB has been hard won and must be intensified. Containing and reversing the epidemic requires immediate and sustained efforts by all stakeholders,” says Dr. Karin Weyer, WHO coordinator for laboratories, diagnostics and drug resistance. “Improved diagnostic tools and access mean that we are detecting and treating more cases. But the gap between detecting and actually getting people started on treatment is widening and we urgently need increased commitment and funding to test and treat every case. In countries such as Estonia and Latvia, where there is universal access to rapid diagnostics and treatment, the number of MDR-TB cases has fallen significantly. This shows what can be achieved.”
A special supplement to this year’s WHO report marks 20 years of anti-TB drug-resistance surveillance. It outlines the MDR-TB response to-date and the priority actions that must now be taken from prevention to cure. Anti-TB drug-resistance surveillance has been a pathfinder in global efforts against antimicrobial resistance (AMR).
Another key challenge is the co-epidemic of TB and HIV. An estimated 1.1 million (13 percent) of the 9 million people who developed TB in 2013 were HIV-positive, with 4 out of 5 cases and deaths occurring in the African Region. While the number of TB deaths among HIV-positive people has been falling for almost a decade, from 540,000 in 2004 to 360,000 in 2013, antiretroviral treatment, preventive therapy and other key interventions still need to be further scaled-up.
Research has a crucial role to play in ending the global TB epidemic and efforts to develop new tools to combat the disease have intensified during the past decade. The research and development pipeline has produced several new diagnostics (such as Xpert MTB/RIF) and two new drugs to treat MDR-TB (bedaquiline and delamanid). Additional rapid tests, new drugs and drug regimens, and vaccines are in clinical trials. However, TB research and development is still severely underfunded.
“In addition to the serious underfunding for research, $8 billion a year is required for TB and MDR-TB prevention, diagnosis and treatment. Domestic and international financing needs to step up to prevent millions of unnecessary deaths,” says Katherine Floyd, WHO coordinator for TB monitoring and evaluation.
The WHO report will be presented and discussed during the upcoming Union World Conference on Lung Health in Barcelona, Spain next week.