Here’s some follow up information from the recent (and probably ongoing) outbreak of Campylobacter infections linked to puppies purchased at Petland stores in the US:
- 55 infected people have been identified now. That’s probably just a fraction of the people who were truly infected, because of the number of steps that need to happen to get on the “identified” list. If someone gets infected, first that person has to be sick enough to go see a physician (many people will just ride it out if it’s not severe). The physician must request a stool sample for testing (not always done, especially if there’s nothing high risk in the patient’s history). The patient must then collect and submit the sample (lots of dropouts on this step). Then, the lab must identify the bacterium, which is perhaps the easiest step in the process. This multi-step pathway is why we assume that reported case numbers are usually dwarfed by the actual number of unidentified cases in an outbreak like this.
- People from 12 US states have been infected. The greatest number were from Ohio (see map).
- Of the 55 infected individuals:
- 14 are Petland employees.
- 35 recently purchased a puppy from Petland, visited a Petland or visited a home where a puppy from Petland lived.
- 4 were exposed to puppies in other places.
- 1 had contact with a person with confirmed Petland-associated illness.
- One had unknown puppy exposure.
As you can see above, the link to Petland is pretty strong. Additionally, testing of the bacteria showed that Campylobacter from Petland puppies were closely related to those from sick people in multiple states.
Concerningly, Campylobacter from these cases generally appears to be resistant to first line antibiotics, something that presumably hampered initial treatment in infected individuals. This includes resistance to azithromycin, erythromycin, clindamycin and ciprofloxacin.
The ultimate source of the outbreak still hasn’t been found (or at least reported). Hopefully it will be identified both to find out what happened and to implement measures to prevent it from happening again.