Cache Valley virus

The Cache Valley virus (CVV) is a member of the Orthobunyavirus genus within the Peribunyaviridae family. It is an arbovirus, meaning it is transmitted by arthropods, primarily mosquitoes. CVV was first isolated in 1956 in the Cache Valley of Utah, United States, and has since been identified in various regions across North America.

Virology

Cache Valley virus is an enveloped virus with a segmented, negative-sense RNA genome. The genome is composed of three segments: the large (L), medium (M), and small (S) segments. These segments encode the viral polymerase, glycoproteins, and nucleocapsid protein, respectively. The virus is primarily transmitted by mosquitoes of the genera Aedes, Anopheles, and Culex.

Epidemiology

CVV is endemic to North America, with most cases reported in the United States. The virus is maintained in nature through a cycle involving mosquitoes and vertebrate hosts, such as deer and livestock. Human infections are rare but can occur, particularly in individuals with occupational exposure to mosquitoes or livestock.

Clinical Manifestations

In humans, Cache Valley virus infection is often asymptomatic or results in mild, flu-like symptoms. However, in rare cases, it can lead to severe neurological disease, including encephalitis and meningitis. Symptoms of severe infection may include fever, headache, muscle weakness, and confusion. There is no specific treatment for CVV infection, and care is supportive.

Veterinary Importance

Cache Valley virus is of significant concern in veterinary medicine, particularly in sheep. Infection in pregnant ewes can lead to congenital malformations, abortions, and stillbirths. The virus can cause severe economic losses in the livestock industry due to these reproductive failures.

Prevention and Control

Preventive measures focus on reducing exposure to mosquito bites. This includes the use of insect repellents, wearing protective clothing, and implementing mosquito control programs. In areas where CVV is prevalent, monitoring and controlling mosquito populations can help reduce the risk of transmission.

Research

Ongoing research aims to better understand the ecology, transmission dynamics, and pathogenesis of Cache Valley virus. Studies are also focused on developing diagnostic tools and potential vaccines to prevent infection in both humans and animals.

Also see

• Orthobunyavirus
• Arbovirus
• Encephalitis
• Mosquito-borne diseases