By the time he escaped, a wound on his left leg had got infected with aggressive bacteria resistant to antibiotics, making it harder for doctors to treat him. Thousands of other soldiers have, like him, come back from the front with wounds festering with multidrug resistant organisms, pointing to a little-understood cost of the war.

Bacteria have long developed resistance against medicines designed to fight them, rendering many drugs useless. The process known as antimicrobial resistance (AMR) directly causes over a million deaths and contributes to five million deaths every year, according to the World Health Organization.

But Ukraine has seen a particular increase in antimicrobial resistance during the Russian invasion, according to WHO representative in Ukraine, Jarno Habicht. “The ultimate cause why we see the rise of antimicrobial resistance is actually the ongoing war,” he said.

“We need to better study the root causes of antimicrobial resistance” as the war continues, said WHO’s Habicht. Part of that research relies on monitoring, said Habicht, who added Ukraine had increased the number of laboratories monitoring drug-resistant bacteria to 100, compared to three in 2017.

The US Centers for Disease Control and Prevention, the public health agency, found that “aggressive bacteria is now spreading beyond Ukraine’s borders”.

Three weeks after AFP visited the hospital, Sushko went back home, his infection under control.