U.S. CDC warns of rise in ‘extensively drug-resistant’ shigella bacteria infections

The U.S. Centers for Disease Control and Prevention (CDC) is warning the public about a rising number of “extensively drug-resistant” (XDR) shigella bacteria infections, also known as shigellosis.

According to a presentation from the agency earlier this week, about 5 per cent of shigella infections reported in the U.S. in 2022 were caused by XDR strains, compared to zero per cent in 2015. The CDC says XDR strains are very hard to treat and can easily spread “antimicrobial resistance genes to other enteric bacteria,” meaning it can make other infections resistant to antibiotics.

Shigellosis is a common cause of travel-associated bacterial diarrhea in the United States and predominately affects gay, bisexual and other men who have sex with men (MSM), people experiencing homelessness and people living with HIV.

In Canada, shigellosis is a nationally notifiable disease, meaning provinces and territories voluntarily report cases to the Public Health Agency of Canada when they are diagnosed if they meet the national case definition.

Health Canada would not provide a statement when asked about the CDC’s warning and whether a similar advisory might be issued here. However, the health agency says the country sees about 880 cases of shigellosis every year.

It doesn’t appear as though Canada has any reported cases of XDR shigella, but an antibiotic-resistant outbreak of shigella bacteria was the subject of a news release in the United Kingdom last month, relating to travellers returning from Cabo Verde. 

The U.S. CDC did not say what the suspected source of the infections being identified in that country may be.

Canadian officials monitor shigellosis cases through FoodNet Canada, PulseNet Canada, the National Enteric Surveillance Program and the Canadian Notifiable Disease Surveillance System.

Shigellosis is contracted by oral contact with material contaminated by feces, commonly via contaminated food or water, according to health officials.

You can also get shigellosis by coming in contact with infected feces, if you don’t practice proper handwashing or if the hygiene habits of those around you are poor.

You can be infected by shigella in your kitchen if you do not wash your hands properly after using the bathroom or handling raw foods. Health Canada also advises you to wash fresh fruits and vegetables before eating them and clean work surfaces thoroughly before and after preparing foods.