In the past, Outbreak Observatory has reported on outbreaks that have resulted from  interaction with, or consumption of, animals both abroad and within the US. For example, a Mongolian couple recently contracted and died from bubonic plague after hunting marmots and eating the raw meat. Additionally, Outbreak Observatory previously reported on how animals such as bats and primates harbor Ebolavirus and how consumption of bushmeat is believed to be the cause of past Ebola outbreaks. A 2016 outbreak of tularemia in Germany was linked to wine contaminated with ground up mice. This week, we report on examples of how domesticated animals, particularly pets, have been linked to outbreaks in the US.

Last week, the US CDC reported multiple Salmonella outbreaks across 21 states from January 12 to April 29 this year. The geographic range of states is vast and includes the West, Midwest, South, and Mid-Atlantic regions of the country. At the time of the report, 52 people had been infected, including 5 hospitalizations; nearly 30% of those infected were children under 5 years old. Even more concerning, whole genome sequencing of 4 isolates indicate possible resistance to several commonly used antibiotics. An outbreak investigation by the CDC identified a source that may be unexpected to some… backyard poultry. Seventy percent of individuals infected reported having contact with backyard poultry prior to becoming sick. Currently, the CDC is investigating hatcheries where the poultry, including chickens and ducks, could have originated. While backyard poultry may not be the most common source of Salmonella infections, 76 Salmonella outbreaks in the US since 2000 have been traced to them. Raising backyard chickens is often a practice in rural areas to access eggs at low cost, but its popularity is expanding. In fact, raising backyard chickens has transformed into a status symbol in Silicon Valley, California, and the San Francisco Bay area has been described as experiencing an apparent “chicken-mania.”

Chickens Aren’t the Only Ones

Over the past few years, domesticated animals have been linked to a myriad of infectious disease outbreaks. In late March, the CDC announced 17 cases of salmonellosis across 11 states, 87% of which were linked to pet hedgehogs. Beginning in October 2018 and extending into March 2019, cases with the outbreak strain were identified primarily in multiple Midwestern states, including Minnesota and Missouri, but were also scattered across the country from Maine to Texas to Washington.

Additionally, from March to December 2017, the CDC reported another animal-associated, multistate Salmonella outbreak that affected 76 people across 19 states. The outbreak resulted in 30 hospitalizations, and 32% of cases were children under 5 years old. A total of 38% of cases reported having contact with pet turtles or contaminated components of turtle habitats. Of those that reported exposure to turtles, 61% reported having contact with small turtles (those with shells less than 4 inches across). While all turtles can carry Salmonella, these tiny turtles are particularly associated with infections in children, in part because children may be more likely to try to stick the turtles in their mouths or kiss them, and thus expose themselves to Salmonella. In fact, selling these turtles has been banned by the US FDA since 1975 because of the high risk of infection. Nevertheless, ownership of tiny turtles has persisted as a result of illegal selling from street vendors, flea markets, and other outlets. If you decide to get a turtle, be sure to measure the size of the shell and go to a reputable pet store. Also, please don’t put it in your mouth, regardless of its size. Turtles hate that.

But you don’t have to own a hedgehog or a tiny turtle to become a victim of your pet’s germs…. More common pets can also share their love through the wonderful gift of diarrhea. In fact, from January 2016 to February 2018, a multistate, multidrug-resistant outbreak of Campylobacter infections was linked to—objectively speaking, of course—the best animals in the world: puppies. While Campylobacter outbreaks in humans are not commonly associated with pet dogs, the Florida Department of Health identified several outbreak-associated infections in August 2017 that were linked to a specific pet store chain from Ohio, based on common isolates identified in stores in both states. The investigation identified 118 cases across 18 states and 6 stores nationwide, including 29 cases in pet store employees. Even more concerning, the isolates were found to be resistant to all front-line antibiotics commonly used to treat Campylobacter infections. The CDC MMWR publication describing the investigation indicated it is possible that high antibiotic use among puppies in pet stores exacerbated drug resistance, since approximately 95% of investigated puppies received at least 1 course of antibiotics. This outbreak illustrated the importance of responsible antibiotic stewardship in the commercial pet industry as well as proper hygiene practices to prevent employees and customers from getting ill.

Can I Still Love My Pet Chicken/Hedgehog/Turtle/Puppy?

Yes, you can. The CDC has published guidance on how to stay healthy while caring for your fur-, feather-, or shell-baby (or whatever hedgehogs would qualify as). For hedgehogs, chickens, turtles, and dogs, the CDC recommends similar safe practices including frequent handwashing after handling your pet and cleaning up any stool or droppings to prevent living spaces from being contaminated. For animals like chickens, hedgehogs, and turtles, it is also important to avoid kissing or snuggling your pet (yes, the CDC actually used the word “snuggle”). Thankfully, that advice doesn’t appear to apply to puppies. The CDC also provides more targeted recommendations, such as avoiding contact with turtles or chicks among children under 5 years old and keeping shoes worn while cleaning chicken coops outside your home.

Concluding Remarks

Many members of the Outbreak Observatory team are pet owners, and we love our pets unconditionally. But these outbreaks illustrate that it is, in fact, possible to be a little too close to your pet. Taking precautions when interacting with domesticated animals, especially for young children, can ensure a happy and healthy relationship with your pets.

Outbreak Observatory aims to collect information on challenges and solutions associated with outbreak response and share it broadly to allow others to learn from these experiences in order to improve global outbreak response capabilities.

Photo courtesy of Pixabay ( )