Postweaning multisystemic wasting syndrome (PMWS) and PDNS continue to account for a large proportion of diagnoses and differ little from diagnoses for the same quarter last year.

VIDA incidents of PCV2-associated diseases (excludes PDNS) (as a percentage of diagnosable submissions) July to September 1999-2005 are illustrated below.

The incidents of PDNS (as a percentage of diagnosable submissions) July to September 1999-2005 are also illustrated:

One investigation identified the first cases of PMWS in a herd. Unlike the situation in many herds, where the introduction of PMWS initially results in high mortality (often >20%), this herd had a postweaning mortality of 2.3% prior to the outbreak, rising to 5% and then to 8% during the first month of the outbreak. Disease presented mainly as scour and wasting.

The absence of certain pathogens in this herd is likely to have reduced concurrent secondary infections and mortality. Increasingly, PCV2-associated disease, sometimes not characterised by wasting as in typical cases of PMWS, is diagnosed in pigs older than 6 to 12-weeks.

In one such incident two deaths occurred in a group of 15 outdoor-reared Gloucester Old Spot boars aged over six-months of age. The main presenting signs were coughing, pyrexia, and anorexia. PCV2 involvement was confirmed in lymph nodes and in pneumonic lung by immunohistochemistry. Another example involved a six-month-old KuneKune that died after a short illness. A profound splenic lymphoid depletion was detected as well as inclusion bodies in renal tubular epithelial cells. Immunohistochemistry confirmed the involvement of PCV2. The in-contact pig recovered after showing malaise.

PDNS remains a significant disease on many units and still causes considerable economic impact. On one occasion swine fever was considered and the DVM was consulted. Some eight percent of a group of finishers had died. PDNS was subsequently confirmed, and swine fever was ruled out. Investigations into high mortality in finishers on four units showed that, whereas PDNS was contributing to losses on two and equivocally in a third, PMWS was not diagnosed on any of the units.

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Source: Veterinary Laboratories Agency (VLA) - December 2005