Working in the emergency department of an inner-city hospital in Europe. The last patient to see on your shift is a young man with a wound to his arm. He does not reveal much about when or how this injury happened. The language barrier is difficult to overcome before you find an interpreter. The wound looks to be infected, likely not well cleaned after the initial injury and is now red, hot and oozing pus. You are concerned he may be septic after you review his observations, so start immediate IV antibiotics and ask the surgeons to examine the wound. But after a couple of hours, his condition is worse. The microbiologist you call for advice asks if he has travelled abroad recently, a question you have not yet explored. You go back with the interpreter and find this young man has been fleeing war, he used to live in Ukraine.

Two studies reporting in Eurosurveillance have highlighted the increase in reporting of multidrug-resistant organisms (MDRO) in Germany and the Netherlands after March 2022, linked to people who have travelled to, fled, or been medically evacuated from Ukraine. Prior to the war, high prevalence of MDRO was reported through the Ukrainian military and general hospital data from 2014-2021, with 17-84% Enterobacterales and P. aeruginosa resistant to third-generation cephalosporins and carbapenems. Alarmingly, over 50% of Acinetobacter species were resistant to carbapenems, fluoroquinolones and aminoglycosides. High levels of MDRO in bloodstream infections in Ukraine had also been reported to the Central Asian and European Surveillance of Antimicrobial Resistance (CAESAR) network in 2021. In many regions/countries including Germany and the Netherlands, MDRO are notifiable through national and regional surveillance to monitor trends and update local, regional and national guidance.

The German and Dutch studies characterised the type of resistant organisms identified from March 2022 onwards. The NDM-1 and NDM-1/OXA-48 carbepenemase-producing Klebsiella pneumoniae reported in Germany was identified from both clinical infections (most commonly wounds) and colonisation from rectal screening on admission. Broader surveillance in the Netherlands noted 21% of all nationally reported carbapenemase-producing Enterobacterales and 52% of all carbapenemase-producing Pseudomonas aeruginosa were from patients originating from Ukraine, around half had been hospitalised in Ukraine. It is important to note however, that the majority of carbapenemase-producing Enterobacterales reported in the Netherlands were associated with travel (non-Ukraine). No outbreaks were identified in either study, indicating all were sporadic cases.

To mitigate the spread of MDROs in day-to-day practice, it is necessary to institute infection prevention and control procedures on admission, when patients are transferred from Ukrainian hospitals as well as other countries with high rates of antimicrobial resistance. These include isolation of the patient and screening for MDRO rectal carriage and MRSA skin colonisation, which were recommended by ECDC. The second practical aspect is to develop interim antimicrobial guidance for treatment of these high-risk patients, which was done in response to the German report suggesting ceftazidime-avibactam in combination with aztreonam may be needed for their carbapenemase-producing K. pneumoniae.

With the movement of people comes the movement of bacteria in their microbiota and their resistance mechanisms, some on mobile genetic elements. People with a history of traveling to countries with high rates of MDR pathogens, and especially hospitalisation in these regions, raise the concern over carriage and disease with MDRO. This is an important part of the individual patient assessment, as it impacts on the choices of antimicrobials we use to most effectively cover the pathogens responsible for their infection. Further monitoring of these trends allows for wider guidance to be issued and alerts raised about new and emerging resistance mechanisms.