The impact of COVID-19 on antimicrobial use and resistant bacteria in the Nordics: a regression modeling approach

Abstract Background Coronavirus disease 2019 (COVID-19) pandemic constituted the largest global health crisis in recent generations and led to economic fallout. It may also have disrupted the pattern of antimicrobial use (AMU) which subsequently affected the development of antimicrobial resistance (AMR). The development of AMR remains a grave human health concern. This study aimed to evaluate the impact of COVID-19 on AMU and AMR in the Nordics. Methods Nordic AMU data (2017-2022) were extracted from national annual reports (for both humans and animals) and the European Surveillance System (TESSy) (for humans only). Nordic human AMR data (2017-2022) were extracted from TESSy. Multilevel linear regression and negative binomial regression models were used to fit the TESSy data. Data between 2017 and 2019 were categorised as the pre-COVID-19 time, while data between 2020 and 2022 were the post-COVID-19 time. Results Denmark had a remarkably greater AMU in animals (about 10 times greater) than Norway, Sweden, and Finland over a 6-year span (2017-2022). Iceland had the highest human AMU, while Sweden had the lowest. Fitting a multilevel linear regression model to human AMU data showed that all variables, except for COVID-19 time, were significant predictors, including drug categories, countries, and sectors (p-values < 0.05). Negative binomial models were used to fit resistant Gram-negative and Gram-positive isolates in the Nordics. The results showed that species, countries, and drug categories were statistically significant predictors. COVID-19 time was only statistically significant in the model fitting the resistant Gram-negative isolate data. Moreover, there were significantly fewer Gram-negative resistant isolates in the pre-COVID-19 time than those in the post-COVID-19 time (p = 0.003, 95% CI: -0.42, -0.09). Among the Nordics, Iceland had the lowest number of resistant isolates; however, lack of national AMR surveillance and high human AMU still remain a great concern for Iceland. Conclusions This study showed that the COVID-19 pandemic had an impact on AMR in the Nordics. This finding underscores the need to establish standardized AMR surveillance at both national and regional levels in the Nordics. Such a standard protocol would facilitate timely information sharing which will improve our preparedness for and response to future pandemics and/or large-scale outbreaks.