Pestiviruses

Pestiviruses are a genus of viruses within the Flaviviridae family. They are small, enveloped viruses with a single-stranded positive-sense RNA genome. Pestiviruses are known for their ability to cause significant disease in a variety of livestock species, particularly ruminants and swine.

The genus is comprised of several species, including Bovine viral diarrhea virus (BVDV), Classical swine fever virus (CSFV), Border disease virus (BDV), and other related viruses. These viruses are antigenically distinct but share common genetic and biological properties. Transmission typically occurs through direct contact with infected animals or their excretions, such as saliva, nasal secretions, urine, and feces. Contaminated fomites and aerosols can also play a role in spread.

Infections with pestiviruses can manifest in a wide range of clinical signs, depending on the viral strain, the age and immune status of the host, and the presence of other infections. Common symptoms can include fever, loss of appetite, diarrhea, respiratory distress, and reproductive failure. Some infections can lead to chronic debilitating conditions or be asymptomatic. A notable characteristic of pestivirus infections is their ability to establish persistent infections, particularly in young animals, which act as reservoirs for virus shedding.

Diagnosis of pestivirus infections is typically performed using serological methods to detect antibodies or molecular techniques like RT-PCR to detect viral RNA in clinical samples. Control and prevention strategies rely on biosecurity measures, vaccination programs where available, and the management of persistently infected animals. Eradication programs for specific pestiviruses, such as Classical swine fever, have been successfully implemented in many regions.