Streptobacillus felis, a member of the oropharynx microbiota of the Felidae, isolated from a tropical rusty-spotted cat.

Streptobacillus felis is a fastidious microorganism and a novel member of the potentially zoonotic bacteria causing rat bite fever. Since its description, this is the second isolation of S. felis in a diseased member of the Felidae. Interestingly, the strain from this study was isolated from a zoo held, rusty-spotted cat (Prionailurus rubiginosus), with pneumonia, thereby indicating a possible broader host range in feline species. A recent preliminary sampling of domestic cats (Felis silvestris forma catus) revealed that this microorganism is common in the oropharynx, suggesting that S. felis is a member of their normal microbiota. Due to unawareness, fastidiousness, antibiotic sensitivity and lack of diagnostics the role of S. felis as a cat and human pathogen might be under-reported as with other Streptobacillus infections. More studies are necessary to elucidate the role of S. felis in domestic cats and other Felidae in order to better estimate its zoonotic potential.

Rat bite fever (Streptobacillus moniliformis) with septicemia in a child.

A 5-year-old girl was admitted to hospital with fever, headache and nausea. Her C-reactive protein raised from less than 11 mg/l to 65 mg/l and she developed a maculopapular, petechial rash, especially pronounced on the soles and palms. After incubation for 3 days, Streptobacillus moniliformis was found in all blood cultures that had been taken. Some weeks before her admission, the girl had been playing with her grandmother's pet rats, which later had died from an unknown disease. There was no history of rat bite. Her condition improved rapidly after treatment with penicillin and chloramphenicol, and she was discharged from hospital after 10 days without sequelae.