Dog and cat saliva may cause deadly infections in humans

The bacterium Capnocytophaga canimorsus, transmissible by saliva of dogs and cats, can be the source of serious or lethal infections in humans.

Capnocytophaga canimorsus, a bacterium found in the saliva of dogs and cats can be very dangerous to humans, according to a study by the University of Brest in France. Published in the journal The Lancet Infectious Disease, the researchers’ observations reveal three deaths in France between February 2017 and April 2018 due to a bacterial infection related to pet saliva. Last August, a 58-year-old American woman succumbed in two days to the bacteria transmitted by her puppy.

In September 2017, a 48-year-old man died of an infection with Capnocytophaga canimorsus at the University Hospital of Caen, two days after being bitten by his dog. In February 2018, another 47-year-old man succumbed to the same generalized infection in Saint-Raphaël. The same year, the bacterium killed a 54-year-old man in Royan hospital (Charente-Maritime). He was living with a dog, but showed no sign of bites or signs of licking on a skin lesion.

Professor Geneviève Héry-Arnaud, co-author of the study, explains: “In 60% of cases, the bacterium was transmitted following a bite. In other cases, after licking a peeled skin. But, sometimes, we do not find the route of entry of the bacteria. The mortality rate in case of infection is estimated to be between 30% and 60% – only in the event of septic shock – when the patient is not treated in time.”

Previously, researchers thought that the infection could only be diagnosed when the immune system of the person was already weakened, for example in the case of cancer, diabetes or AIDS. However, the last case at Royan Hospital did not present immunosuppression.

“This case recalls the extreme potential severity of the rare sepsis C. canimorsus and illustrates the fact that this is possible without context immunosuppression and no concept of inoculation (introduction of the bacterium in the body, ed),” noted the scientists. They recall: “This rare and difficult diagnosis is to be considered in any patient with a severe and brutal infectious syndrome, especially in case of recent contact with a dog or a cat”. According to the Center for Disease Control and Prevention, the bacteria Capnocytophaga canimorsus is 75% in dog saliva and 57% in cats.

When it does not kill, the infection can also lead to amputations. A 48-year-old man from Wisconsin had to have his legs and parts of his arms amputated after contracting this rare blood infection. Other cases are also reported in the study.

Thus, the researchers indicate that any infection occurring within 48 to 72 hours after a bite, even if it does not look worrying, requires urgent medical consultation. “In the case of a serious infection with no etiology (factors of a disease, ed), antibiotic treatment should be considered if the patient lives near a domestic animal, especially if there are lesions skin or a history of bite, “they write.

Shakes Gilles

Editor of The Talking Democrat. He enjoys bike riding, kayaking and playing soccer. On a slow weekend, you'll find him with a book by the lake.