It would be easy to think that tuberculosis is under control. TB, one of the world’s top two infectious disease killers, has been declining slowly but steadily and in some parts of the world it has been almost eradicated.
But one of the oldest epidemics afflicting mankind has come back with a new face: drug-resistant tuberculosis (DR-TB) is on the rise globally and experts warn that deadly strains are spreading at an alarming rate, threatening to unravel much of the progress made in tackling TB.
Around 450,000 people fell sick with these dangerous superbug strains of TB in 2012, according to the World Health Organisation (WHO). Fewer than one in four were diagnosed, putting the rest at risk of dying due to the wrong medicines or no treatment at all.
Patients with multi-drug resistant TB (MDR-TB) fail to respond to treatment with two of the powerful anti-tuberculosis drugs. Totally-drug resistant TB, which cannot be treated with any known drugs, is also rising. The cost of treating these forms is high - £250,000 compared to £5,000 for conventional TB, and the side effects are even worse.
TB strains resisting conventional treatment are present in virtually all countries, according to the WHO. The BRICS countries of fast-growing economies – Brazil, Russia, India, China and South Africa – account for more than half of cases.
Although the burden is biggest in sub-Saharan Africa and south Asia, TB is also making a comeback in developed countries. In the UK, where it was almost eradicated, all forms of TB are rising. Public health statistics show that London has become the TB capital of Western Europe, with infection rates in some parts in the east and north of the capital higher than those of Nigeria and Malawi.
WHY IS TB SO HARD TO CONTROL?
One of the biggest problems is that it can be very difficult to find and diagnose people infected with TB. About a third of the estimated 9 million that contract the disease in any form every year don't get treatment and could be unintentionally infecting 15 and 20 people through airborne droplets they produce by coughing and sneezing.
As a result the WHO expects that 1.4 million people will die from TB this year, or almost 4,000 every day, a number that health experts say is far too high for a treatable and curable disease.
Complicating matters is that about 1/3 of the world’s population have latent, or silent TB, meaning they have been infected by tuberculosis bacteria but have not (yet) fallen ill. They have a 10 percent chance of getting active TB, in particular if their immune systems are impaired or if they live in crowded conditions or suffer from malnutrition.
Even though new tools for diagnosing MDR-TB are becoming more widely used, only one in five people who need it can obtain treatment, according to Medecines Sans Frontieres (MSF).
No matter where a patient lives, treatment can take two years and involves swallowing up to 20 pills a day and more than 200 painful injections over the course of the treatment, with potentially severe and long-lasting side effects.
The European Centre for Disease Control said last week only one third of MDR-TB patients finish the treatment successfully. Globally, fewer than 10 percent of all MDR-TB patients are cured.
WHAT CAN BE DONE TO BEAT TB?
The global response to TB has, so far, struggled with chronically low levels of funding as much more attention and money has been given to AIDS and malaria treatment, campaigners say.
TB drugs have not changed for almost half a century. Newer, shorter, less toxic and more affordable treatments are key to turning the DR-TB crisis around, health experts say but MSF estimates that only 30 percent of the necessary funding to beat TB is available.
Experts say it is high time for a renewed global effort by governments, pharmaceutical companies and researchers to fight TB. This week more than 160 parliamentarians from across the Group of 7 industrialised countries and the European Parliament released a statement calling for more global commitment to drive down rates of TB by investing more in research and development of new drugs, diagnostics, vaccines and better diagnosis tools.
“Diagnosing and treating everyone with TB is the bare minimum of what we should expect,” said Nick Herbert MP, co-chairman of the UK All Party Parliamentary Group on Global Tuberculosis.
“The unfortunate truth is that our current systems simply aren’t good enough, we need new ideas.”