An outbreak of Clostridioides difficile infections due to a 027-like PCR ribotype 181 in a Greek rehabilitation clinic.. C. difficile RT181

Clostridioides difficile is one of the most important healthcare-associated pathogens. A decade ago, the so-alled “ hypervirulent” PCR ribotype 027 caused large outbreaks worldwide. Recently, a number of new 027-like types have been found that all belong to the multilocus sequence typing (MLST) Clade 2. We identified a rapidly spreading outbreak of C. difficile infections (CDI) at orthopedic and neurological wards in a Greek 180-bed Rehabilitation Clinic (RC) within a 28-day time-period in 2019. The CDI incidence rate on the RC quadrupled to 49 infections per 10,000 patient days. All patients had been previously hospitalized in 7 different hospitals, suffered from co-morbidities and received antibiotic therapy within three months before the C. difficile episode. The outbreak strain was identified as PCR ribotype (RT) 181, belonged to sequence type (ST) 1 and had a 18bp deletion in tcdC at position 311 together with a single nucleotide deletion at position 117, similarly to RT 027. The outbreak was associated with mild to moderate disease and only 6% of the patients developed a relapse. We conclude that new C. difficile ribotypes still emerge and that C. difficile RT 181 was rapidly spreading but not associated with increased mortality and higher relapse rates.