Botulism outbreak in Utah prison linked to homebrew, baked potato

An outbreak of the deadly toxin Clostridium botulinum at a Utah prison last year was caused by a tainted batch of a prisoner-brewed alcoholic beverage called pruno, according to a report from the Centers for Disease Control and Prevention. The offending ingredient: a moldy baked potato added at the last minute.

Eight prisoners became seriously ill as a result of the brew, making it the largest botulism outbreak in the U.S. since 2007.

The beverage is usually made from fruit, sugar and water, which are fermented in plastic bags under cushions and piles of clothing to keep the temperature as high as possible. In the botulism-tainted batch, a prisoner had also added an old baked potato taken from the prison cafeteria.

CDC epidemiologists believe the toxin was produced when the potato, which sat at room temperature for several weeks, was added to the sealed plastic bag: The low-acidity, anaerobic environment is ideal for toxin growth, the investigators noted.

(Homebrewers of beer need not worry: The conditions that allow for the growth or survival of Clostridium botulinum are not present during beer production.)

Since the Utah botulism outbreak, another group of four prisoners in an Arizona facility have also gotten sick from pruno -- and they also used potato in their mix.

The investigators note that pruno is in high demand in prisons, so it’s not going away. Rather, medical personnel and administrators should be on the watch for cases of botulism, and should work to inform inmates to the threat -- particularly from potato and root vegetables.

You can read the CDC’s report here.

Return to the Booster Shots blog.