WHO’s new priority list of antibiotic-resistant bacteria looks beyond the scourge of tuberculosis

Effective antibiotics are a cornerstone of global public health. They protect us from potentially fatal diseases and ensure that complex procedures, such as surgery and chemotherapy, can be provided at low risk. In recent years, numerous bacteria that cause infections in humans and animals have become insensitive to existing antibiotics, leaving us without a line of defense against these common and often serious infections.

Specific diseases, such as drug-resistant tuberculosis (TB), have long been recognized as a global research and development priority, with a substantial history of advocacy for increased research. Most recently, the 2016 Global Tuberculosis Report and the End TB Strategy clearly state that research and development is one of the three priority areas for action to control the disease. High-level political conferences and meetings, including the World Health Organization’s Global Ministerial Conference taking place in Moscow later this year and the United Nations General Assembly in 2018, will both highlight the need for increased TB research.

To respond to the growing challenge of antibiotic resistance, the WHO launched in 2015 a global action plan on antimicrobial resistance, with specific global objectives and recommendations. One of those recommendations was to create incentives for the research community and industry to develop new antibiotics for other infections that no longer respond to available treatments.

To help governments, researchers, and industry focus their efforts on antibiotic resistance, the WHO recently published a priority list of 12 antibiotic-resistant bacteria. Through this list, the WHO aims to guide the development of new antibiotics to fight microbes that have never before been high priorities for this work at a global level, but which are emerging as serious risks to patients and communities around the world.

See the related First Opinion: The World Health Organization made a big mistake on TB. It must fix it

The scientific analysis underpinning the list did not include drug-resistant Mycobacterium tuberculosis, the bacterium that causes TB, because the chief goal was to alert researchers and policy makers to as-yet unrecognized new threats.

The absence of M. tuberculosis from the priority list sparked considerable criticism from the TB community. Some saw it as an oversight, others as an attempt to take funding and attention away from this important disease.

It was neither. The WHO global priority list of antibiotic-resistant pathogens clearly states that TB “is already a globally established priority for which innovative new treatments are urgently needed.” The goal of this report is to highlight research and development needs in addition to, and beyond, those directed toward antibiotic-resistant TB. For example, it identifies for the first time some strains of the “gram negative” class of bacteria as global health threats. Some of these pathogens are now resistant to most or all available treatments, resulting in increased illness and death from bacterial infections, and contributing to escalating health care costs.

Gram-negative bacteria included in the list are Acinetobacter baumannii, which causes infection mainly in health care settings; Pseudomonas aeruginosa, which causes bloodstream infections and pneumonia in hospitalized patients; and Klebsiella pneumoniae, which causes many types of health care-associated infections, including pneumonia, urinary tract infections, and bloodstream infections.

The rationale used to develop the priority pathogens list was based on several criteria: how deadly are the infections they cause; whether their treatment requires long hospital stays; how resistant they are to existing antibiotics when people in communities get infected with them; how easily they spread from animal to animal, from animals to humans, and from person to person; whether they can be prevented (through good hygiene, vaccination, and the like); the number of treatment options that remain; and whether new antibiotics to treat them are already in the research and development pipeline.

I urge researchers to turn their attention to antibiotic-resistant pathogens, such as Mycobacterium tuberculosis and those highlighted on the new priority list, so we can begin to curb alarming trends in antibiotic resistance in our hospitals and our communities. Moving forward, the WHO will continue to consult with the scientific community on the value of prioritizing other groups of pathogens using the same approach.

TB and other major infectious diseases, such as HIV and malaria, will remain global priorities and continue to be the focus of increased incentives for research and development. But we must also pay attention to other looming threats, so science can deliver effective treatments to all patients.

Marie-Paule Kieny, PhD, is the World Health Organization’s assistant director-general for health systems and innovation.