Rat bite fever (also called Streptobacillary fever; Haverhill fever; Spirillary fever; Sodoku) is an acute, rare disease caused by two different bacteria Streptobacillus moniliformis in North America and Spirillum minus in Asia. Rats are carriers of bacteria but rarely show signs of illness. Disease has been reported in mice, birds, guinea pigs, and nonhuman primates. The majority of cases are due to the animal's bite. It can also be transmitted throughout food or water that is contaminated with rat feces or urine. The disease is most often seen in Asia, Europe, North America. The exact incidence is unknown. It was first reported in the U.S. in 1839.
Symptoms depend on the bacteria that caused the infection and include chills, recurrent fever, joint pain, redness, or swelling. Symptoms usually occur 3-10 days after exposure to an infected rodent, but can be delayed as long as 3 weeks. The disease is diagnosed by isolating S. moniliformis from blood, synovial fluid, or other body fluids. Rat bite fever can be treated readily with antibiotics, but untreated S. moniliformis infections are estimated to be fatal. It may cause complications like infection of the brain or soft tissue, infection of the heart valves, inflammation of the parotid glands, the tendons and the heart lining.