Jamestown Canyon encephalitis

Jamestown Canyon encephalitis is a mosquito-borne viral disease caused by the Jamestown Canyon virus (JCV). It is a member of the California serogroup of viruses, which are a group of Orthobunyaviruses known to cause encephalitis in humans.

Epidemiology

Jamestown Canyon encephalitis is found primarily in North America, with cases reported in the United States and Canada. The virus is transmitted to humans through the bite of an infected mosquito, primarily the Aedes and Culex species. The virus has been isolated from a wide range of mammalian hosts, including deer, which are thought to be the primary reservoir of the virus.

Clinical Presentation

The majority of infections with Jamestown Canyon virus are asymptomatic. However, when symptoms do occur, they typically begin with a sudden onset of fever, headache, nausea, and fatigue. In severe cases, the virus can cause encephalitis, an inflammation of the brain, which can lead to seizures, coma, and in rare cases, death.

Diagnosis

Diagnosis of Jamestown Canyon encephalitis is typically made through serologic testing, which involves testing a patient's blood for antibodies to the virus. Other diagnostic methods include polymerase chain reaction (PCR) testing, which can detect the virus's genetic material in a patient's blood or cerebrospinal fluid.

Treatment and Prevention

There is no specific antiviral treatment for Jamestown Canyon encephalitis. Treatment is supportive and may include hospitalization, respiratory support, and treatment of other complications. Prevention of Jamestown Canyon encephalitis primarily involves avoiding mosquito bites through the use of insect repellent, wearing long sleeves and pants, and staying indoors at dusk and dawn when mosquitoes are most active.

See Also

• California encephalitis virus
• La Crosse encephalitis
• Snowshoe hare virus