Multidrug-resistant Rhodococcus equi (MDR-RE): detection in East Asia confirms global spread

ABSTRACT Rhodococcus equi is an aerobic pathogenic actinomycete that causes severe pyogranulomatous infections in equids and other animals, as well as in humans through zoonotic transmission. Macrolide- and multidrug-resistant R. equi (MDR-RE) emerged in the early 2000s and has since spread across horse farms in the United States. Following its detection in Europe (Ireland) in 2016, we report here its isolation in Japan, along with evidence of its presence in China. Indications of continued importation into Ireland are also presented. These findings underscore the ongoing international dissemination of MDR-RE and its potential for global establishment. IMPORTANCE Our findings indicate that the recently identified multidrug-resistant Rhodococcus equi (MDR-RE) continues to expand geographically through horse movements and is now globally disseminated, posing a risk of becoming prevalent in equine-breeding regions worldwide. Although currently circulating among horses, MDR-RE can emerge in other animals and humans over time. Early detection and active surveillance are essential to monitor and control the spread of this emerging zoonotic antimicrobial resistance threat.