the bacteria through touching contaminated surfaces with an open wound or mucous membrane or ingestion of contaminated water or food by rodent feces, though this is referred to as Haverhill Fever (epidemic arthritic erythema). RBF is not a contagious disease. That is, it cannot be transferred directly from person to person. Researchers are challenged in understanding the prevalence of RBF. One factor that limits the known number of cases of RBF in the United States is that it is not a reportable disease there. RBF is classified as a notifiable disease, which means it is required by the state to be reported, however, the state is not mandated to provide that information to the United States Centers for Disease Control. Identification of RBF is also hindered due to the presence of two different etiological bacterial agents, Streptobacillus moniliformis and Spirillum minus. RBF caused by Sp. minus is more commonly found in Asia and is termed Sodoku, whereas St. moniliformis is found more often in the United States and in the Western Hemisphere. Although cases of RBF have been reported all over the world, the majority of cases that have been documented are caused by St. moniliformis primarily in the United States, where approximately 200 cases have been identified and reported. Due to increasing population density, this illness is being seen more frequently, as humans have increased their contact with animals and the zoonotic diseases they carry. Most cases of the disease have been reported from densely populated regions, such as big cities. The populations at risk have broadened due to the fact that domestic rats have become a common household pet. 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)