In February this year, the World Health Organisation (WHO) published the first global priority pathogens list of antibiotic-resistant bacteria, bringing attention to 12 families of bacteria that “pose the greatest threat to human health — and for which new antibiotics are urgently needed.”

The list – divided into critical, high and medium priority – was welcomed by global public health experts, who unanimously agreed that the superbug problem was one that required critical attention. Others, however, have highlighted a flaw in the list in which they said should be corrected immediately.

The experts who compiled the list have failed to include Mycobacterium tuberculosis – the bacterium that causes tuberculosis (TB).

WHO: Tuberculosis already a top global priority

Approximately 10.4 million people around the globe were infected with TB in 2015 – a statistic derived by the WHO itself – and out of the total, 580,000 incidences were drug-resistant.

It has become extremely challenging to treat drug-resistant TB. Affected individuals are required to take large doses of uncommon and high-priced antibiotics for long periods of time, sometimes for as long as two years, of which may result in harmful side effects.

But only one out of every five individuals with drug-resistant TB manages access to adequate treatment. The rest, unfortunately, do not receive treatment and may succumb to the disease.

So why was the pathogen exempted from the list?

According to the WHO, Mycobacterium tuberculosis was not considered for review as “it is already a globally established priority for which innovative new treatments are urgently needed.”

“Mycobacterium tuberculosis, the bacterium responsible for human TB, was not included in the scope of the prioritisation exercise as the intention was to identify previously unrecognised health threats due to increasing antibiotic resistance. There is already consensus that TB is a top priority for R&D for new antibiotics,” explained Dr Marie-Paule Kieny, assistant director-general at WHO.

Organisations stress need for more attention on TB

However, some experts have expressed their dismay that the bacterium excluded from the list – a critical advocacy and reference tool designed with specific intention for guiding policymakers in decision-making and priorities for pharmaceutical research and development.

No doubt, there is an urgent need for newer antibiotics for treating the pathogens that were listed by the WHO, but several organisations debate that the pathogen causing tuberculosis should continuously be highlighted as an alarming threat to global health, as sidelining the antibiotic-resistant pathogen from the priority list risks damaging the current efforts in TB research.

Antibiotics against tuberculosis were used for the first time back in 1944, but up until today, there are fewer than 20 agents that work against mycobacterium. Two new medicines, bedaquiline and delamanid, were approved in 2012 and 2014 respectively, but their access is limited to only a small number of patients with the most resistant strains.

Support for research and development of new TB antibiotics is declining, and the disquiet lies in the fear that exclusion of TB from the list may further reduce attention from the disease.

“Most people don’t know that it’s such a big burden because TB has been neglected for so long,” said Lucica Ditiu, executive director of Stop TB Partnership.

However, WHO Director-General Margaret Chan has reaffirmed that the critical need for research and development of drug-resistant TB has not been overlooked.

“Addressing drug-resistant TB research is a top priority for WHO and for the world,” she reassured. “More than US$ 800 million per year is currently necessary to fund badly needed research into new antibiotics to treat TB.” MIMS

Read more:
WHO announces 12 families of superbugs that pose the greatest threat
Singapore scientists lead fight against TB in two novel researches
Superbugs a growing concern in Southeast Asian hospitals