In a report published on Monday, the WHO said that a historic lack of focus on the danger of fungal infections meant there were significant gaps in knowledge on treatments and diagnostics.
A total of 19 fungi were listed as a danger to public health. They were divided into three categories based on their potential impact and risk: critical, high and medium priority.
The report found that fungal infections receive less than 1.5 per cent of all infectious disease research funding and said treatment guidelines were “informed by limited evidence and expert opinion”.
“Emerging from the shadows of the bacterial antimicrobial resistance pandemic, fungal infections are growing and are ever more resistant to treatments, becoming a public health concern worldwide,” said Dr Hanan Balkhy, WHO assistant director-general for antimicrobial resistance.
Candida auris is among those listed in the critical group and is known to cause bloodstream and ear infections. It is highly drug resistant and has caused a number of outbreaks in hospitals worldwide.
The WHO warned that the pathogen is “intrinsically resistant to most available antifungal medicines” and has “high outbreak potential”.
The critical list also includes candida albicans, the most common cause of thrush.
Dr Justin Beardsley, a scientist at the University of Sydney Infectious Diseases Institute who led a group commissioned by the WHO, said fungal infection rates had spiked during the pandemic.
“We suddenly had a bunch of patients who were getting really sick, coming in with lung damage, being in intensive care and having immune-suppressing medications, and so we saw a spike in the rates of these infections,” he said.
The high group includes Mucorales, which contains the fungi that causes “black fungus” — an infection which rose dramatically in seriously ill people during the Covid pandemic.
Only four types of treatments exist, with very few new options in the development pipeline. Climate change also means that the incidence and geographic range of the pathogens is expanding, the WHO said, while resistance is in part being driven by the over-use of antifungals in agriculture.