Hospitals in Ukraine are now battling an “alarming increase” in germs with resistance to the last-ditch antibiotic medications used to treat the infections, a study published by the U.S. Centers for Disease Control and Prevention reported Thursday. 

Officials are now calling for the “urgent crisis” to be addressed, and warning that the drug-resistant germs are spreading beyond the war-torn country’s borders.

The researchers, including scientists from the CDC and Ukraine’s health ministry, sampled hundreds of Ukrainian patients for infections they caught while being treated at the hospital in November and December last year. 

Their surveys, detailed in the CDC’s Morbidity and Mortality Weekly Report, found that about 60% of patients with infections were battling germs resistant to carbapenem antibiotics. The CDC describes these kinds of antibiotics as often the “last line of defense” doctors wield to fight off bacteria after other options fail to work.

By contrast, just around 6.2% of samples of similar kinds of infections were resistant to carbapenem antibiotics in an European study through 2017. 

“In Ukraine, the confluence of high prewar rates of antimicrobial resistance, an increase in the prevalence of traumatic wounds, and the war-related strain on health care facilities is leading to increased detection of multidrug-resistant organisms with spread into Europe,” the study’s authors wrote.

For years, health officials have been warning of the mounting antimicrobial resistance threat posed by the ongoing conflict in Ukraine. 

The CDC’s European counterpart warned in March 2022 that hospitals should preemptively isolate and screen patients from Ukraine for multidrug-resistant organisms.

Germany reported last year seeing infections from drug-resistant bacteria climb “rapidly” after March 2022 across the country, linked to refugees and evacuated patients from Ukraine.

The biggest increases in Germany were for drug-resistant Klebsiella pneumoniae, while others similar germs did not see large jumps, suggesting that increased screening could not explain the surge in reports of the worrying bacteria. 

Klebsiella is part of a larger group of germs called Enterobacterales that has been developing resistance to carbapenem antibiotics, which the CDC has deemed an “urgent” public health threat. 

In the U.S., these drug-resistant bacteria are estimated to make up more than 13,000 cases and 1,000 deaths each year. Around 5% of Klebsiella samples in 2021 were reported to be resistant, according to CDC data. 

In the study published Thursday, all the Klebsiella samples they tested from the Ukrainian patients were resistant to carbapenem antibiotics.

Other drug-resistance threats have also been spotted in Ukraine. 

In July, U.S. military doctors treating a Ukrainian soldier said they had found the patient had been infected by six different “extensively drug-resistant bacteria,” including Klebsiella pneumoniae, after he suffered traumatic burns across more than half of his body.

“Isolates were nonsusceptible to most antibiotics and carried an array of antibiotic resistant genes,” the doctors wrote, in a report published by the CDC’s Emerging Infectious Diseases journal.

To effectively respond to the growing threat, the CDC’s report said health officials in Ukraine will need more training and supplies to buoy hospitals treating infected patients during the war. 

Labs in Ukraine have also struggled to secure enough supplies and manpower to test infections for resistance, which is key not just for assessing the scope of the threat but also for guiding doctors to decide on how to treat difficult infections.

“To address the alarming increase of antimicrobial resistance in Ukraine, UPHC with assistance from international partners, is developing locally led and implemented measures to address antimicrobial resistance and will need ongoing support to scale them nationally,” they wrote.