TB, disease of the poor, now threatens the rich; “TB has killed more people than all other pandemics combined”

March 24, 2014 12:01 am

TB, disease of the poor, now threatens the rich

By Andrew Ward

Its victims have included George Orwell, Frederic Chopin, Franz Kafka, Emily Brontë and Eleanor Roosevelt.

If tuberculosis were still killing such cultural giants, it would not be hard to attract attention and funding to the campaign for its eradication.

Yet, today, even though it kills 1.3m people a year, TB is the poor relation of global diseases, struggling to match the resources attracted by more high-profile causes such as HIV.

In 2013, research spending on TB by the US National Institutes of Health amounted to $266m, compared with $2.9bn on HIV/Aids, despite the two diseases causing a similar number of deaths.

“TB has killed more people than all other pandemics combined,” says Aaron Oxley, executive director of Results UK, an anti-poverty group. “But it has been with us for thousands of years and it is a slow disease. Aids is all about sex and drugs. TB is about coughing and spitting. Which are people more likely to want to get involved in?”

Despite the funding difficulties, significant progress has been made. Incidence of TB has been falling steadily for a decade and the mortality rate is down 45 per cent since 1990 – within reach of the target for a 50 per cent reduction by 2015 set in the UN’s Millennium Development Goals.

By some estimates, TB accounts for more than half the estimated 8.7m lives saved by the Global Fund to fight Aids, TB and Malaria since its launch in 2002, despite receiving only 16 per cent of the funding. Such figures are hard to pin down but few would dispute that the TB programme has produced a good return on investment.

“I can’t think of another field of public health where so much has been achieved with so little but progress is painfully slow,” says Mel Spigelman, director of research and development at TB Alliance, a non-governmental organisation.

While headline numbers are coming down, a closer inspection reveals how much more is still to be done. Of the 8.6m people estimated to contract TB each year, 3m do not receive diagnosis and treatment, according to the World Health Organisation.

Mr Oxley said the likely success in meeting the Millennium Goals on TB was no cause for celebration. “Every day 3,000 people still die from this disease which shows that the goals were very unambitious. We’re coming from a long way back.”

TB – a bacterial infection that usually affects the lungs and spreads through sustained contact between people living or working in proximity – has been a scourge of humanity for millennia. Fragments of the spinal column from Egyptian mummies show clear signs of the disease and possible traces were detected in the skull of a fossilised Homo erectus – early human ancestors – dating back about 500,000 years.

Today, TB has been mostly banished from the rich world aside from pockets of vulnerability among impoverished communities in cities such as London. But it remains one of the greatest public health risks in many low- and middle-income countries, where 95 per cent of fatalities occur. India, China, South Africa, Indonesia and Pakistan top the list in terms of volume of cases.

Efforts to tackle the disease are being complicated by the rise of drug-resistant strains – a consequence of poor management of existing medicines by doctors and poor compliance by patients. Special treatments are available to overcome drug-resistance but they are costlier and longer-lasting with more severe side effects and lower levels of effectiveness.

There was a breakthrough last year when US regulators approved a new treatment for multi-drug resistant TB (MDR-TB) by Johnson & Johnson, the first new TB medicine of any kind for 40 years. Another, from Otsuka of Japan is also on the launch pad. While welcoming the new treatments, activists say they will not change the landscape on their own.

“Even if you have new drugs you need the public health infrastructure to diagnose patients, deliver the drugs and ensure adherence to the treatment,” says Neil Schluger, chief scientific officer of the World Lung Foundation. “That is still lacking in many parts of the world.”

A big push is under way to improve detection with the introduction of testing equipment that can shorten the time to diagnosis from weeks to a few hours – and with increased accuracy. Many diagnoses still take place using the same slide and microscope technique pioneered by Robert Koch, the German microbiologist who won the 1905 Nobel Prize for Medicine for his work on the disease.

But this is beginning to change as 1.4m state-of-the-art testing kits are distributed to 21 countries under a $26m scheme backed by the WHO, the Stop TB Partnership and Unitaid, a Geneva-based funding body.

A sample of a patient’s sputum is deposited in a cartridge which clicks into a device that looks similar to an espresso machine.

Philippe Duneton, executive director of Unitaid, says the technology, called GeneXpert, has already helped increase detection in India and South Africa. Uptake has been encouraged by a cut in the previously prohibitive cost of cartridges from $18 to $10 each.

Work is also continuing on potential vaccines, despite the failure last year of the first large clinical trial of a new TB vaccine for nearly a century. The £30m programme led by Oxford university tested the MVA85A vaccine on 2,800 South African children but failed to show a positive impact on immune response.

Ann Ginsberg is chief medical officer of Aeras, a US non-profit organisation focused on developing a vaccine for TB. She says there are about 12 further potential vaccines being tested but the cost, length and complexity of full-scale trials remain obstacles.

Other areas of research include links with HIV, diabetes and smoking, all of which increase the risk of developing TB.

Overall, global spending on TB-focused research and development fell by $30m to $627m in 2012, according to the latest report by the Treatment Action Group, which monitors investment in HIV and TB programmes. This leaves annual R&D funding far below the $2bn targeted by the Global Plan to Stop TB.

Private sector companies cut spending by 22 per cent to leave them accounting for just 18 per cent of the total – a sign of most drugmakers’ reluctance to invest in a disease concentrated among poor people in poor countries.

Public funding accounted for 61 per cent and philanthropic organisations, such as the Bill and Melinda Gates Foundation, provided 20 per cent.

Money for treatment and diagnostic programmes is also tight, with the WHO last year reporting a $1.6bn annual shortfall in the $4.8bn needed. “Many countries around the world are not contributing their fair share,” says Mr Spigelman.

As well as rich nations, he says developing Bric countries must also help out given their growing wealth and big TB problems. “India and China are putting in more resources but they tend to focus on domestic initiatives rather than taking part in international efforts.”

Mr Schluger says: “The biggest challenge is for people to realise how much TB is out there. The rate is going down 2 per cent a year but that is too slow for eradication to happen for decades to come.”