infectious diseases
Rat Bite Fever
Streptobacillary rat bite fever
Streptobacillary rat-bite fever is caused by the pleomorphic gram-negative bacillusS. moniliformis, an organism present in the oropharynx of healthy rats. Epidemics have been associated with ingestion of unpasteurized milk contaminated byS. moniliformis(Haverhill fever), but infection is usually a consequence of a bite by a wild rat or mouse. Other rodents and weasels have also been implicated. The primary wound usually heals promptly, but after an incubation period of 1 to 22 (usually<10) days, a viral-like syndrome develops abruptly, causing chills, fever, vomiting, headache, and back and joint pains. Most patients develop a morbilliform, petechial, or vesicular rash on the hands and feet about 3 days later. Migratory polyarthralgia or septic arthritis, usually affecting the large joints asymmetrically, develops in many patients within 1 week and, if untreated, may persist for several days or months. Fever may return, occurring irregularly over a period of weeks to months. Infective Endocarditis , Haverhill fever (erythema arthriticum epidemicum) resembles percutaneously acquired rat-bite fever but with more prominent pharyngitis and vomiting. 