Porcine circovirus type 2 (PCV2) is a single-stranded DNA virus. viral infection by itself tends to cause only mild disease, however, it can develop into what is known as postweaning multisystemic wasting syndrome (PMWS). PCV2 infection is widespread and essentially all pig herds are infected with PCV2. The disease is characterized by wasting and infertility among infected herds, causing great economic impact.
PCV2 is considered a ubiquitous virus as it has been reported worldwide. Transmission may be by direct contact with infected pigs. PCV2 has been detected in almost all potential excretion routes such as nasal, ocular, and bronchial secretions. This makes saliva, urine, and feces particularly dangerous. The virus can also be transmitted vertically from mother directly through the uterus or during lactation.
Clinical signs typically appear in pigs 9 to 12 days post-infection, with mortality beginning 10 to 21 days. Symptoms may last up to 6 weeks. These include:
- Weight loss
- Respiratory distress
- Porcine dermatitis and nephropathy syndrome
- Enlarged, depleted lymph nodes
- Increased mortality and cull rates
- Occasional reproductive disorders