User:Cjn2075/Rat-bite fever

Rat-bite fever (RBF) is a zoonotic disease that was first reported in la Réunion, France in 2009. It can be directly transmitted by rats, gerbils, and mice (the vectors) to humans by either a bite or scratch or it can be passed from rodent to rodent. The causative bacterial agent of RBF has also been observed in squirrels, ferrets, dogs, and pigs. The most common reservoir of the disease is rats because nearly all domestic and wild rats are colonized by the causative bacterial agent, Streptobacillus moniliformis. Most notably, the Black rat (Rattus rattus) and the Norwegian rat (Rattus norvegicus) are recognized as potential reservoirs due to their common use as laboratory animals or kept as pets. The bacteria Streptobacillus moniliformis is found in the rat's upper respiratory tract. Most rats harbor the disease asymptomatically, and signs and symptoms rarely develop. It is estimated that 1 in 10 bites from a rat will result in developing RBF. A person is also at risk of acquiring 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 knowing the prevalence RBF. One factor that limits the known number of cases of RBF is that it is not a reportable disease. Rat-Bite Fever 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 CDC at the federal level. 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) 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.

Eliminating exposure is very important when it comes to disease prevention. When handling rodents or cleaning areas where rodents have been, contact between hand and mouth should be avoided. Hands and face should be washed after contact and any scratches both cleaned and antiseptics applied. The effect of chemoprophylaxis following rodent bites or scratches on the disease is unknown. No vaccines are available for these diseases. Improved conditions to minimize rodent contact with humans are the best preventive measures. Animal handlers, laboratory workers, and sanitation and sewer workers must take special precautions against exposure. Wild rodents, dead or alive, should not be touched and pets must not be allowed to ingest rodents. Those living in the inner cities where overcrowding and poor sanitation cause rodent problems are at risk from the disease. Half of all cases reported are children under 12 living in these conditions.