PMWS & PCV2
PMWS is associated with infection of pigs by porcine circovirus type 2 (PCV2). However, the exact relationship between PCV2 infection and PMWS remains unclear. There is not a straightforward relationship between infection and disease. PCV2 has a near universal distribution – present in most pig herds. In contrast, PMWS is more sporadic in its distribution. Experimental induction of PMWS has not been achieved by PCV2 infection alone, using infectious DNA clones of the virus or a pure form of PCV2 derived from infectious DNA clones. Therefore it is assumed that PMWS is a multifactorial disease. PCV-2 is necessary but not sufficient for the development of PMWS. There is no significant correlation of the disease with virus sequence variation with affected and control pigs.
Read more about this topic: Postweaning Multisystemic Wasting Syndrome