A dog in France appears to have contracted monkeypox from his owners, in what seems to be the first known case of human-to-dog transmission of the emerging viral illness. The dog likely caught the infection while sleeping in the same bed as his owners.
A team of infectious disease doctors based primarily at the Pitié-Salpêtrière Hospital in Paris, France published their report last week in the Lancet.
On June 10, two men visited the hospital with symptoms of monkeypox, namely a distinctive rash along with headaches, general weakness, and fever. As with the majority of monkeypox cases documented in non-endemic areas of the world this year, their infections appeared to be transmitted through prolonged close contact during sex. The men were living together and in a relationship but non-exclusively, and both developed a rash about a week after they had sex with other men. PCR testing then showed that they contracted monkeypox.
Twelve days after their symptoms appeared, the pair noticed that their dog—a healthy male 4-year-old greyhound—began to display similar rashes and lesions around its abdomen and anus. PCR testing would show the presence of monkeypox in the poor pooch as well, and subsequent genetic sequencing found that the virus collected from the dog was a match for the virus collected from one of the patients, essentially confirming the chain of transmission. The owners also reported that they were regularly co-sleeping with their dog.
Monkeypox is believed to be natively carried by rodents in parts of Africa, but it’s capable of infecting a variety of mammals through close contact and possibly respiratory droplets. It was first identified in the 1950s among lab monkeys imported from Africa (hence the somewhat misleading name). By the 1970s, it was shown that humans could occasionally contract the infection from contact with infected animals. This year, however, the virus has spread far wider than ever before through sustained person-to-person transmission. And this is the first documented case of monkeypox in a dog or any domesticated animal, according to the report authors. (An outbreak in the U.S. nearly 20 years ago was linked to pet prairie dogs, which are not domesticated animals.)
There have been over 30,000 reported cases of human monkeypox outside non-endemic areas of the world this year, including over 11,000 in the U.S. alone. And while there are available vaccines and treatments available, experts fear that these outbreaks will allow the virus to establish itself as an ongoing human illness from now on. If so, monkeypox may spread primarily as a sexually transmitted infection, but there have already been reports of non-sexual transmission between members of the same household. And the authors say that their report should serve as a red flag about the possible risk of transmission to pets.
“Our findings should prompt debate on the need to isolate pets from monkeypox virus-positive individuals. We call for further investigation on secondary transmissions via pets,” they wrote.
The report notes that the owners were careful to keep their dog away from other people and animals since the onset of their own symptoms. But it doesn’t go into further detail on the outcomes of any of the patients. Most cases during this outbreak have been relatively mild and self-limiting. About 10% of people have needed hospitalization, though, usually to manage the severe pain that symptoms can cause. There have also been five deaths reported outside of Africa, but none in France to date.