Three people in Minnesota have fallen ill with salmonella, part of a national outbreak that health authorities have linked to pet hedgehogs.
Officials have confirmed 20 cases in eight states since December 2011, the U.S. Centers for Disease Control and Prevention (CDC) said Friday.
Four people have been hospitalized and one has died in Washington state.
After an investigation, the center concluded that the strain came from contact with hedgehogs, which have become popular pets in some parts of the country.
Fourteen of 15 patients interviewed by the CDC reported contact with a hedgehog or its environment before getting sick.
While investigators haven't determined how common salmonella is in the small spiny mammal, they said the bacteria is common in a variety of small animals, including reptiles, amphibians and poultry.
"Animals can appear healthy and clean but still carry the pathogen salmonella," said Tara Anderson, a CDC epidemic intelligence officer.
The CDC said people who touch hedgehogs or their environments should take extra care to follow basic hygiene practices such as washing hands. Pet owners should avoid washing out terrariums or feed bowls in kitchen sinks to avoid contamination, according to Kirk Smith, supervisor of the foodborne diseases unit for the Minnesota Department of Health.