On 27 February, WHO published its first ever list of antibiotic-resistant ‘priority pathogens’ – a catalogue of 12 families of bacteria that pose the greatest threat to human health.
The list was drawn up in a bid to guide and promote research and development (R&D) of new antibiotics, as part of WHO’s efforts to address growing global resistance to antimicrobial medicines. The list highlights in particular the threat of gram-negative bacteria that are resistant to multiple antibiotics. These bacteria have built-in abilities to find new ways to resist treatment and can pass along genetic material that allows other bacteria to become drug-resistant as well.
The WHO list is divided into three categories according to the urgency of need for new antibiotics: critical, high and medium priority.
The most critical group of all includes multi-drug resistant bacteria that pose a particular threat in hospitals, nursing homes, and among patients whose care requires devices such as ventilators and blood catheters. They include Acinetobacter, Pseudomonas and various Enterobacteriaceae (including Klebsiella, E. coli, Serratia, and Proteus). These can cause severe and often deadly infections such as bloodstream infections and pneumonia.
These bacteria have become resistant to a large number of antibiotics, including carbapenems and third generation cephalosporins – the best available antibiotics for treating multi-drug resistant bacteria.
The second and third tiers in the list – the high and medium priority categories – contain other increasingly drug-resistant bacteria that cause more common diseases such as gonorrhoea and food poisoning caused by Salmonella. [Source: WHO News Release, 27 February 2017. http://www.who.int/mediacentre/news/releases/2017/bacteria-antibiotics-need…]