Brussels imposed rules in July that live exports – for breeding and production – must be accompanied with certificates saying that the pigs were PEDv-free and had not been anywhere near an infection. This system was authorised until 12 January, but the outbreak seems to be continuing.
The US Department of Agriculture (USDA) animal and plant health inspection service reported 22 newly infected farms between 23 and 29 November, and said there had been 554 such cases since 5 June. And in Canada, according to a November bulletin from the World Organisation for Animal Health (OIE), Ontario has reported nine additional outbreaks since the disease first struck in January, with two more reported in the province of Manitoba.
The EU controls, said the new regulation, imposed on 8 December by the European Commission, included "necessary guarantees at the holding of origin… to prevent the introduction of porcine epidemic diarrhoea caused by those viruses into the [European] Union". The regulation noted advice from the European Food Safety Authority (EFSA) that animals, their faeces, feed and objects contaminated with faeces "have been reported to transmit those viruses".
These create novel swine enteric coronavirus disease caused by emerging porcine alphacoronaviruses, including PEDv and the porcine deltacoronavirus. The Commission move to extend the rules has also been backed by the EU’s standing committee on plants, animals, food and feed.
Research highlighted by the American Association of Swine Veterinarians has suggested that the virus could also spread through the air. "Results indicated the presence of infectious PEDv in the air from experimentally infected pigs and genetic material of PEDv was detected up to 10 miles downwind from naturally infected farms. Airborne transmission should be considered as a potential route for PEDv dissemination," said an association note on the study.
From Monday (15 December), USDA will require American farms to submit Premises Identification Numbers (PINs) with diagnostic samples if they want free tests for the disease. The USDA argues PINs help track emerging diseases such as PEDv when diagnosed on a farm.