Investigation Update: Salmonella outbreak, Pet Bearded Dragons - October 2022

March 3, 2023

CDC and public health officials in several states investigated two multistate outbreaks of Salmonella infections with serotypes Vitkin and IIIb 61:z52:z53.

Epidemiologic and laboratory data showed that contact with pet bearded dragons made people sick in both outbreaks.

Epidemiologic Data

As of March 3, 2023, a total of 32 people infected with the outbreak strains of Salmonella Vitkin (12 people) and Salmonella IIIb 61:z52:z53 (20 people) were reported from 20 states (see map). Illnesses started on dates ranging from March 21, 2021, to December 22, 2022 (see timeline).

Sick people ranged in age from less than 1 to 75 years, with a median age of 8 years old. Fifteen (47%) were children under the age of 5 years old, with 11 children under the age of 1 year old. Of 30 people with sex information available, 19 (63%) people were female. Of 25 people with information available, 10 (40%) were hospitalized.No deaths were reported.

The true number of sick people in an outbreak is likely much higher than the number reported, and the outbreak may not be limited to the states with known illnesses. This is because many people recover without medical care and are not tested for Salmonella.

State and local public health officials interviewed people about the animals they came into contact with during the week before they got sick. Of the 26 people interviewed, 17 (65%) reported contact with a pet bearded dragon before getting sick. Contact most frequently occurred at people's homes and included touching the animals or their enclosures, feeding them, and putting them on the lap, head, or shoulders.

Laboratory and Traceback Data

Public health investigators used the PulseNet system to identify illnesses that were part of this outbreak. CDC PulseNet manages a national database of DNA fingerprints of bacteria that cause gastrointestinal illnesses. DNA fingerprinting is performed on bacteria using a method called whole genome sequencing (WGS).

WGS showed that bacteria from sick people's samples are closely related genetically. This means that people in each outbreak likely got sick from the same type of animal.

In both outbreaks, 15 people reported purchasing their bearded dragons from pet stores or online. The stores reported sourcing bearded dragons from multiple breeders and suppliers, several in common between both outbreaks. The stores reported sourcing bearded dragons from multiple breeders and suppliers, of which several were common between the two outbreaks.

Salmonella Vitkin outbreak

• Among the 8 people who reported contact with bearded dragons, 4 reported purchasing their bearded dragon from different pet stores.

Salmonella IIIb 61:z52:z53 outbreak

• Utah and Colorado public health officials identified the outbreak strain from samples collected from a sick person's bearded dragon and its habitat.

• Among the 9 people who reported contact with bearded dragons, all reported purchasing or having contact with bearded dragons from different pet stores. At least five breeders and suppliers were identified, including one that supplied multiple stores.

WGS of bacteria from 30 people's samples, seven bearded dragon samples, and 30 environmental samples predicted resistance to ciprofloxacin; analysis of bacteria from one person's sample did not predict resistance to any antibiotics. Most people with Salmonella illness recover without antibiotics. However, if antibiotics are needed, this resistance could affect the choice of antibiotic used to treat some people. Testing of bacteria from three people's samples using standard antibiotic susceptibility testing methods by CDC's National Antimicrobial Resistance Monitoring System (NARMS) laboratory showed nonsusceptibility to ciprofloxacin, meaning that clinicians would need to select an alternate antibiotic if treatment were indicated.

Public Health Actions

CDC advises that you always take steps to stay healthy around your pet bearded dragon:

• Wash your hands.

• Don't kiss or snuggle your bearded dragon.

• Keep your bearded dragon out of the kitchen and away from areas where young children play.

• Keep its supplies and habitat clean.

• Limit young children's contact with your bearded dragon.