Porcine Cytomegalovirus (PCMV)
(208) This is a herpes virus found in the tissues throughout the body including the nose of newborn piglets where it causes inflammation (rhinitis). PCMV is present throughout the world and exists in most if not all pig populations but most infections are sub-clinical and clinical disease is rare. Serology carried out in the UK, for example, indicates that over 90% of herds have been exposed to infection.
The virus is excreted in discharges from the nose and eyes, urine and farrowing fluids. It is also transmitted via the boar through semen and crosses the placenta to infect piglets before birth.
The rhinitis produced by this virus is uncommon and mild and has no relationship to atrophic rhinitis caused by the toxin-producing bacteria Pasteurella multocida. In most herds therefore the infection is insignificant and apart from sometimes causing a mild sneeze has no major effect on the health of the pig.