LAUSR

This report is produced each month by the APHA Surveillance Intelligence Unit and the six Species Expert Groups (livestock and wildlife). The international horizonscanning summaries are produced by the Defra/APHA International Disease Monitoring (IDM) team, notifiable disease reports by the APHA Veterinary Exotic and Notifiable Disease Unit (VENDU), and threat analysis by the cross-agency Veterinary Risk Group (VRG). The report is drawn from scanning surveillance information, data and reports produced by the APHA Veterinary Investigation Centres and non-APHA partner postmortem examination providers contributing to the VIDA database and complying with standardised diagnostic and laboratory testing criteria. Other livestock and wildlife scanning surveillance reports may also be found at www.gov.uk/government/collections/animal-disease-surveillance-reports Disease and threats summary African swine fever virus and imported pork products There are ongoing concerns around pork products from non-EU countries entering the EU in passenger luggage and then being discarded in areas where wild boar or domestic pigs are present. With regular direct flights to the EU, including the UK, from China and eastern Asia, there is a risk of entry of African swine fever (ASF) virus in products of animal origin from Asia. Numerous media accounts in 2019 have reported the movement of illegal pork products and ASFinfected pork products from China. In June 2019, as part of routine activities, port authorities in Northern Ireland seized a total of 300 kg of meat and dairy products illegally carried by passengers during the month. A sample of one of these seizures, a sausage originating from Asia, was tested at the Agri-Food and Biosciences Institute, resulting in the detection of ASF virus DNA fragments. Although the presence of ASF DNA does not necessarily mean that the meat was infectious, it underlines the potential risk to the UK from pork and pork products being brought (VIC) on a three-and-a-half-monthold suckler calf. It was one of four affected calves in a group of 16 with their dams in a North Yorkshire herd of 110 animals. Within 48 hours of being turned onto pasture, one calf in the group had exhibited weakness, dyspnoea and tachypnoea. The three other calves also developed similar signs within a few days. White muscle disease was suspected and a parenteral selenium injection was administered to some of the calves. The calf that was examined postmortem had become isolated from the others the day before it was submitted and subsequently died. Purulent pneumonia was present in the right cranial lung lobe and there were petechial and ecchymotic haemorrhages on the surface of the heart. Histopathology of the heart indicated multifocal, subacute myocardial necrosis with mineralisation, and in skeletal muscles, which showed pallor, there was multifocal, subacute myocyte necrosis with fibrosis. The lesions were consistent with a nutritional myopathy and biochemical analysis detected 0.24 mg/kg dry matter (DM) liver selenium concentration (reference interval 0.9–1.75 mg/kg DM), which confirmed hyposelenaemia. White muscle disease is most commonly diagnosed in the late spring (Fig 1) and usually in suckler calves. In this case the calves had access to a pelleted creep feed when housed, with rolled barley and silage also available. After being turned onto pasture they continued to be fed creep feed and had access to straw. However, the very low liver selenium concentration indicated that little or none was eaten, which was reflected at postmortem examination with only liquid green forage in the rumen White muscle disease is most commonly diagnosed in the late spring and usually in suckler calves illegally into the country. The UK has not confirmed an outbreak of ASF, and there has never been an outbreak of ASF in the UK. The finding in Northern Ireland does not affect the UK’s ASF disease-free status. Since the spread of ASF into the eastern EU, control measures have been put in place to ensure that no live pigs, wild boar or pork products from affected areas reach the UK. The government is working closely with the pig sector and other stakeholders to raise awareness of the risks and provide advice on maintaining high biosecurity standards.