In the United States it is estimated that children 5 years and younger are the most at risk, receiving 50% of the total exposure, followed by laboratory personnel and then pet store employees. Other groups at increased risk are people over 65 years old, immunocompromised individuals, and pregnant women.Symptoms of RBF include sudden high temperature fevers with rigors, vomiting, headaches, painful joints/arthritis. A red, bumpy rash develops in about 75% of subjects. Symptoms of RBF can develop between 3 days and 3 weeks after exposure. While symptoms differ between Streptobacillary and Spirillary RBF, both types exhibit an incubation period before symptoms manifest. Due to its symptoms, RBF is often misdiagnosed by clinicians, leading to lingering symptoms and worsening conditions in patients; left untreated the mortality rate (death rate) of RBF is 13%. Even when treated, RBF can lead to migratory polyarthralgia, persistent rash, and fatigue  which can persist for weeks to years after initial infection and treatment. See also
Pasteurellosis
List of cutaneous conditions
Zoonosis

References
Rat Bite Fever (RBF) | CDC

Further reading
"Rat-bite Fever (RBF)". Centers for Disease Control and Prevention. Retrieved 28 February 2014. Centers for Disease Control Prevention (CDC) (January 2005). "Fatal rat-bite fever—Florida and Washington, 2003". MMWR Morb. Mortal. Wkly. Rep. 53 (51): 1198–202. PMID 15635289. Rat-bite fever (MyOptumHealth.com)
Tandon, R; Lee, M; Curran, E; Demierre, MF; Sulis, CA (Dec 15, 2006). "A 26-year-old woman with a rash on her extremities". Clinical Infectious Diseases. 43 (12): 1585–6, 1616–7. doi:10.1086/509574. PMID 17109293. Centers for Disease Control, (CDC) (Jun 8, 1984). "Rat-bite fever in a college student--California". MMWR.
Both spirillary and streptobacillary rat-bite fever have a few individual symptoms, although most symptoms are shared. Streptobacillosis is most commonly found in the United States and spirillary rat-bite fever is generally diagnosed in Africa. Rat-bite symptoms are visually seen in most cases and include inflammation around the open sore. A rash can also spread around the area and appear red or purple. Other symptoms associated with streptobacillary rat-bite fever include chills, fever, vomiting, headaches, and muscle aches. Joints can also become painfully swollen and pain can be experienced in the back. Skin irritations such as ulcers or inflammation can develop on the hands and feet. Wounds heal slowly, so symptoms possibly come and go over the course of a few months. Symptoms associated with spirillary rat-bite fever include issues with the lymph nodes, which often swell or become inflamed as a reaction to the infection. The most common locations of lymph node swelling are in the neck, groin, and underarm. Symptoms generally appear within two to ten days of exposure to the infected animal. It begins with the fever and progresses to the rash on the hands and feet within two to four days. The rash appears all over the body with this form but rarely causes joint pain. Causes
Two types of Gram-negative, facultatively anaerobic bacteria can cause the infection. Spirillosis
Rat-bite fever transmitted by the Gram-negative coiled rod Spirillum minus (also known as Spirillum minor) is rarer, and is found most often in Asia. In Japan, the disease is called sodoku.