No cases have been detected in Great Britain, but APHA is asking vets to remain vigilant for suspicious symptoms
British pig vets have been told to watch for an unusual disease syndrome reported in the Netherlands and Denmark, although no cases have been detected in Great Britain.
The condition, predominantly seen in young pigs, can cause striking symptoms including bulging eyes, abnormal eye alignment, reddened or wrinkled skin, hair loss and poor growth.
The Animal and Plant Health Agency (APHA) has issued an emerging disease alert after the syndrome was identified on a number of pig farms in the Netherlands and at a breeding unit in Denmark.
Investigations have associated the condition with a previously unidentified variant of parvovirus, but scientists have not yet established whether the virus is directly responsible for the disease.
APHA said there is currently no evidence that the syndrome poses a human health or food safety risk.
Affected pigs have typically been between two and 10 weeks old, including sucking piglets and weaners, although some of the distinctive eye abnormalities have also been reported in gilts and finishing pigs.
Two of the most unusual signs are bulging eyes, known clinically as exophthalmos, and abnormal eye alignment, or strabismus.
Pigs may also develop widespread reddening and wrinkling of the skin, hair loss, respiratory signs and uneven or reduced growth.
APHA said the combination of unusual eye abnormalities and skin changes in several animals should raise suspicion among vets.
Levels of disease can be high within affected groups.
In some reported outbreaks, up to 80% of pigs in around half of litters have been affected at the same time.
Despite the potentially high level of illness, mortality directly associated with the syndrome has so far been low and most affected pigs have recovered.
Outbreaks on European farms have lasted between three and six months, with an average duration of around four months.
Other problems reported on affected units have included peri-weaning diarrhoea, greasy pig disease and uneven batches of pigs, which can lead to poorer-quality finishers.
Investigators have repeatedly detected high levels of a previously unidentified parvovirus variant in affected pigs in both the Netherlands and Denmark.
The same variant has not been detected in healthy pigs examined during the investigations.
However, APHA stressed that this does not yet prove the virus is the cause of the syndrome, with further epidemiological and experimental work needed.
There is currently no information showing whether the new virus variant is present in pigs or wildlife in Great Britain, and officials say too little is known about how the condition spreads to assess the risk of it reaching British herds.
Existing commercial vaccines used against established forms of porcine parvovirus are not expected to provide protection against the newly identified variant.
APHA is now asking vets in England and Wales who encounter pigs with similar clinical signs to contact their nearest Veterinary Investigation Centre or surveillance pathology provider.
Suspect cases that closely match the syndrome seen in the Netherlands and Denmark may qualify for APHA-funded investigation.
The agency will fund post-mortem examinations of a batch of three pigs in suitable cases, with samples tested as part of efforts to identify whether the novel parvovirus variant is present.
Vets can also provide images or video footage of suspicious animals to help APHA determine whether further investigation is warranted.
For British pig producers, no additional disease-control measures have been recommended at this stage.
However, vets are being asked to remain alert for unusual combinations of eye, skin and growth abnormalities, particularly in young pigs, as surveillance continues.