This week the World Health Organization (WHO) released a priority list for pathogens for which new drugs are urgently needed to combat.
The list includes 12 families of bacteria divided into three categories: critical, high and medium priority. Among the critical group includes Pseudomonas aeruginosa, which causes skin infections in humans – some strains have been found to be resistant to many antibiotics.
Multi-drug resistant groups in the critical category can pose particular threats in hospitals, nursing homes, for patients reliant on ventilators and blood catheters, and for transplant patients or those in intensive care.
“This list is not meant to scare people about new superbugs,” said WHO assistant director-general Dr Marie-Paule Kieny. “It’s intended to signal research and development priorities to address urgent public health threats.”
“Antibiotic resistance is growing, and we are fast running out of treatment options. If we leave it to market forces alone, the new antibiotics we most urgently need are not going to be developed in time.”
University of Auckland’s Dr Siouxsie Wiles told Newshub, “it’s very clear it’s not something the market is going to fix and that’s why the WHO have put this list out.”
“The problem is that those diseases, they never really went away they were just treatable. Now they’re becoming untreatable and so we risk going back to what it was like before.”
A notable absence from the list was Tuberculosis, which the WHO said was already targeted by dedicated programmes.
The University of Otago provided expert commentary on the announced list, please feel free to use these comments in your reporting. See this expert Q&A for more details on antimicrobial resistance.
Professor Kurt Krause, professor of biochemistry, University of Otago, comments:
“The World Health Organization has done a good job in compiling this global list, which includes all of the resistant organisms prominently featured in media and medical reports, plus a few extra that may be a little less well-known.
“Topping the list are Acinetobacter, Pseudomonas and Enterobacteriaceae.
“These three Priority 1 targets include many strains that are carbapenam resistant, and carbapenam is a very powerful antibiotic often reserved for the most serious infections. They also include a few strains that are effectively resistant to all antibiotics and almost untreatable.
“Priority 2 targets include six organisms such as Enterococcus, Staphylococcus aureus, Campylobacter and Neisseria gonorrhoeae, the last being the cause of a common form of sexually transmitted infection.
“The first two are included for resistance to vancomycin and methicillin respectively and the last two for fluoroquinolone resistance. Recently particular strains of N. gonorrhoeae have become resistant to multiple drugs raising the spectre of untreatable STI.
“Finally, the Priority 3 list includes Streptococcus pneumoniae, Haemophilus and Shigella. These are two primarily respiratory pathogens and one intestinal pathogen.
“From a New Zealand perspective, the most important members on this list would include Campylobacter, Streptococcus pneumoniae and Staphylococcus aureus.
“Campylobacter, an important cause of gastrointestinal disease, continues to dominant the list of New Zealand reportable diseases, with a rate of about 150 cases per 100,000 population. However, some clinicians feel this is an underestimate, with as many as 1 per cent of New Zealanders having this illness yearly.
“Significant numbers of Streptococcus pneumoniae and Staphylococcus aureus infections also occur annually in New Zealand.
“Each year about 100,000 people here are hospitalised with infection as the primary cause, and this represents about 10 per cent of all hospitalizations. More than 60 per cent of these infections are bacterial in nature, when the cause can be determined. This suggests that controlling bacterial disease is an important goal in New Zealand.
“This country is generally quite fortunate concerning antibiotic resistance. Levels of antimicrobial resistance in New Zealand are, for most of the pathogens on the list, between three and 10-fold less than the most affected countries. Also, the most highly resistant strains, which are not sensitive even to colistin or tigecycline – drugs of last resort – have not yet been reported here.
“Although this is good news, it is important not to become complacent. Because of globalisation, antibiotic resistance of even the most severe nature can arrive at any airport or any port at any time. And in general, resistant strains usually spread across the world in time.
“One approach to the antimicrobial-resistance issue is:
- Use antibiotics appropriately, taking them as directed and only for bacterial infections;
- Minimise and eliminate unwarranted and unneeded use in people, plants and animals;
- Maintain an effective surveillance network of trained microbiologists; and
- Support the development of new antibiotics for resistant organisms and use them wisely.
“Finally, as we work to address these severe threats, it is important to remember that the great majority of bacteria are not pathogens and many, if not most, are very helpful. In addition, many pathogens colonise our skin and gastrointestinal tracts without causing disease.
“By learning more about how they grow and function, we are likely to uncover breakthroughs that could over time develop into something even better than antibiotics for treating and preventing disease.
“It goes without saying that we are behind in this struggle and the time for doing this work has to be now.”