Live cultures of Candida auris, an emerging fungus that presents a serious global health threat and is resistant to most antifungal agents, have been isolated and documented in the ear canals of hospitalised stray dogs in the capital.
Candida auris is an emerging multidrug-resistant oval-shaped fungus causing life-threatening outbreaks, often in healthcare settings. This fungal pathogen has been rated as an urgent threat by the U.S. Centers for Disease Control and Prevention (CDC) and classified as a critical priority group by the World Health Organisation (WHO).
Dog-human transmission unclear
“Our report documents for the first time the isolation of live C. auris culture from an animal source. Overall, 4 of the 87 dogs (4.5%) contained evidence of C. auris infection or colonisation in their ear and on the surface of their skin,’’ said the study. Titled Candida auris in Dog Ears, the study was conducted by scientists from Delhi University and Canada’s McMaster University, and published on June 30 in the Journal of Fungi.
Though the study highlighted the isolation of C. auris from an animal source, it noted that the routes of transmission of this yeast to dogs — and the clinical significance of transmission between dogs and humans — still remain to be investigated. The paper does suggest that pets can act as reservoirs for superbugs, potentially transmitting infections to humans.
Multidrug-resistant
Candida auris, a species of fungus that grows as yeast, is one of the few species of the genus Candida which causes candidiasis in humans. Often, candidiasis is acquired in hospitals by patients with weakened immune systems. First reported in Japan in 2009, C. auris has since spread all over the world.
The CDC has previously alerted and expressed concern about C. auris, as some strains are resistant to all three available classes of antifungals, making treatment difficult. Additionally, the fungus is hard to identify with standard laboratory methods and can be misidentified in labs without specific technology. Misidentification may lead to inappropriate management, and has caused outbreaks in healthcare settings, the CDC said. The public health agency encourages all U.S. laboratory staff who identify C. auris to notify their state or local public health authorities as well as CDC.
Strays with skin infections
For the study, researchers — from the Vallabhbhai Patel Chest Institute, Ramjas College, and Delhi University — tested skin and ear swab samples from 87 dogs in the in-patient department of Delhi’s Sanjay Gandhi Animal Care Centre. They found evidence of C. auris within the ear canals of four of the animals with chronic skin infections. The swabs were analysed for bacteria and fungi cultures using routine diagnostic protocols for skin and ear infections.
Of the 87-dog sample, 52 were strays already under intensive care for severe lesions from chronic skin diseases. The remaining 35 dogs were household pets being treated for minor gastrointestinal and urinary infections. Their conditions were not related to the pathogen under study.
The study noted that, outside hospital settings, C. auris has been isolated from the surface of stored apples, tidal marshes, hypersaline environments, and recently from wastewater, suggesting that this yeast can survive in harsh conditions.
