In recent weeks, cases of Aujeszky’s disease have been detected in three wild boar farms in Allier (Auvergne-Rhône-Alpes), in the neighboring department of Creuse, reports the World Organization for Animal Health (OIE).
Non-transmissible to humans, this highly contagious disease, which mainly affects pigs and wild boars, is fatal for dogs. This is why these cases worry hunters in particular. Here’s what we know about this relatively rare virus in the country.
Not transmissible to humans
According to the Federal Agency for the Safety of the Food Chain, Aujeszky’s disease is a highly contagious viral disease caused by a Herpes virus and for which there is no treatment. It mainly affects pigs and wild boars, whether wild or domestic. When a pig is infected, it remains a carrier of the virus for life and transmits it to its congeners via its saliva, its nasal and genital secretions. Symptoms in these animals are variable, ranging from fine to severe respiratory problems, including neurological or reproductive disorders, with a low mortality rate in adults (2%).
It is not transmissible to humans, but it can infect other species, including dogs, cats, horses, and cattle, which cannot transmit the virus, not even among themselves. If the symptoms are also variable, including respiratory failure, cough, fever, compulsive scratching and convulsions, the outcome is still fatal for other species that contract the disease and die within 48 to 72 hours.
A rare disease in France…
Although very contagious, the disease is quite rare. Because if there is no treatment, there is still a vaccine for pigs. According to the Ministry of Agriculture, “the vaccination and hygiene measures implemented in the 1980s made it possible to eradicate the disease in most of French territory”.
The last outbreaks of Aujeszky’s disease in breeding on French territory date back to September 2010, in New Aquitaine, in the Pyrénées-Atlantiques and in the Landes. Since then, metropolitan France has been recognized as “free” from the disease in pig farms and vaccination is therefore no longer practiced there, as in many other countries of the European Union.
But the disease continues to circulate in wild boars. This explains why contaminations occur from time to time in farms.
… But several cases recently detected
Since the start of the year, according to France 3 Auvergne-Rhône-Alpes, cases have notably been detected in three farms in the Allier, in Chevagnes and Montbeugny at the start of the year, then in Beaulon in early April. In the latter case, “the contamination was allegedly made through the park fence, by other specimens of non-captive wildlife,” said the OIE report.
This multiplication of cases in the same department worries breeders since as soon as an animal is infected, all the livestock is slaughtered. A crawl space must then be respected before resuming activity, which constitutes a blow for the industry. Hunters are also worried and call on dog owners to be vigilant, in particular at the end of confinement, so that their animals do not suffer the same fate as the four dogs who died in Dordogne last December after contracting the disease.
These three cases are not the first since France was declared free from the disease on farms. A case of Aujeszky’s disease was notably confirmed last December in Haute-Garonne. Before that, in April 2019, cases had led to the slaughter of one farm in the Alpes de Haute-Provence and another in the Vaucluse. And in March 2018, a farm in the Pyrénées-Atlantiques was slaughtered following the discovery of a case. Proof that the disease, although rare, continues to circulate.