Did WHO’s TB care advice cause more MDR-TB cases?

SEM photo of Mycobacterium tuberculosis bacteria. - Photo NIAD-Optimized

A scanning electron microcope picture of Mycobacterium tuberculosis bacteria. – Photo: NIAD

Between 1993 and 2002, the World Health Organisation violated sound medical care by urging low- and middle-income countries to follow less expensive, largely untested and ineffective treatment protocols to treat people with multidrug resistant TB (MDR-TB), says a paper published on June 21, 2016 in the Health and Human Rights Journal.

Cost factor was the main consideration for the WHO to not recommend the available standard of care used successfully to treat MDR-TB cases in rich countries. The paper, by Thomas Nicholson from the Sanford School of Public Policy, Duke University, Durham and others, accuses the WHO of practising double standard for TB care in low- and middle-income countries by virtue of being the advisor to donor agencies and governments.

For instance,  rifampin, a potent TB drug cured TB in 6-9 months. While it became the bedrock of TB treatment in rich countries, due to cost considerations, low- and middle-income countries did not have access to the medicine till such time the patent expired in 1987. “Before then, many public health experts advocated more toxic, less effective drugs for use in poor countries,” the authors note.

For most of the 1990s, donors and governments were told “not to treat MDR-TB patients” but instead focus on preventing the emergence of such cases. “Weak health systems in poor countries, lack of capacity to implement complex health interventions, and even scientifically disproven ideas that drug-resistant strains would not be as transmissible” were the rationalizations forwarded by the WHO for this policy, says the paper. “However, the driving force was a concern over cost.”

In the late 1980s, outbreaks of MDR-TB were reported all over the U.S, most notably in New York City. In the early 1990s, New York City successfully prevented transmission of MDR-TB by treating patients with recently acquired disease promptly, appropriately, and completely —ideally, with directly observed therapy (DOT).

In 1995 MDR-TB outbreak was reported in a slum area in Lima, Peru. Even as the guidelines for treating drug-resistant TB were drawn up by the WHO, the global health body advised the Peru government to use an “untested standardised therapy”. And unlike in the case of New York City, no drug sensitivity testing was involved. So patients received drugs to which they were already resistant to. “Unsurprisingly, only 48 per cent achieved cure and a significant number died. Many acquired further drug resistance,” says the paper.

However, an NGO Partners in Health (PIH) in Peru rejected the WHO’s treatment regimen and adopted the same approach as in New York City after tailoring to the local needs and demonstrated that a higher cure rates — 66 per cent validated cure for all enrolled MDR patients— could be achieved.

“For many countries, the MDR-TB epidemic worsened from 1995 to 2005,” the paper says. Belarus adopted the WHO treatment protocols that was rejected by PIH and U.S. CDC and six years later nearly half of diagnosed TB patients had MDR-TB or XDR-TB. “The WHO’s persistence in choosing to recommend sub-standard treatment regimens due to cost for treatment of DR-TB in these countries clearly had deadly stakes,” the paper notes.

“While championing the cost-sensitivity of its standard protocol for low-resource settings, it was insufficiently sensitive to the protocol’s fundamental biomedical adequacy for large groups of patients. Far from an ambitious program to stop TB using the drugs known to combat the disease and improve patient health, the protocol arguably set up millions to miss the boat of effective treatment,” the paper highlights.

A press release from Duke University says that despite second-line drugs becoming available in 2002 for treating MDR-TB patients in low- and middle-income countries, the WHO guidelines on treatment of MDR-TB patients were not rewritten till 2006. Salmaan Keshavjee, a co-author from the Department of Global Health and Social Medicine, Harvard Medical School, Boston, served on the committee that rewrote the guidelines.

According to WHO, globally, 190,000 people died of MDR-TB and an estimated 480,000 cases occurred in 2014 alone. Of these, only 123,000 were detected and reported, even fewer received appropriate treatment, and only half of those treated were cured. Between 2000 and 2009, an estimated 5 million people were infected with MDR-TB.

With TB being an airborne disease, advocating different standards of treatment for rich and poor countries runs counter to good public health policy.

Published in The Hindu on June 26, 2016