Invasive Enterovirus and Parechovirus Infections in Adults, Alberta, Canada, 2023-2025.

We conducted a retrospective, population-based laboratory surveillance study during May 2023-December 2025 in Alberta, Canada, to characterize adult invasive enterovirus and parechovirus infections and to identify groups at high risk for those infections. Of 15,621 samples tested, 162 (1.0%) were virus positive, of which 51 (31.5%) samples from 39 patients indicated invasive infections. Cerebrospinal fluid, blood, and cardiac tissue were the most frequent virus-positive specimens. The invasive enterovirus and parechovirus incidence rate was 0.37 cases/100,000 person-years; rates were higher in patients <50 versus >50 years of age (incidence rate ratio 8.2; p<0.001). The annual incidence rates were 0.20-0.56 cases/100,000 person-years; rates appeared higher in 2025 than in 2024 (incidence rate ratio 2.1; p = 0.11). Severe disseminated enterovirus infection occurred in 2 patients who received ocrelizumab. Continuous surveillance and ongoing optimization of enterovirus and parechovirus detection assays is essential for comprehensive public health tracking.