Late 2025, 73.1% of Denmark’s pig farms officially was negative for Porcine Reproductive and Respiratory Syndrome (PRRS) virus.
Those data were communicated by the Danish Agriculture and Food Council (L&F), in personal correspondence with Boerderij, a Dutch-language sister title to Pig Progress.
Another 3.5% of the farms has completed a partial depop-repop. That group of farms is in the phase in which testing is ongoing whether or not the virus has really vanished from the farms. A 3rd group of 21.3% of farms is still positive for PRRS virus. Of a remaining group of 2.2% the status is unknown – that group includes farms that could simply be empty.
A chewing rope is a method to obtain insights in the PRRS status of a herd. Photo: Bert Janssen
PRRS reduction plan since 2022
The Danish swine industry has been aiming to get negative for PRRS on 85% of its sow farms and 75% of its finisher farms mid-2026. The Danish pig industry started its PRRS reduction plan in 2022, at a moment when 53.6% of the sow farms was negative for PRRS, as well as 22.5% of its finisher farms.
In 2025, altogether 74 swine farms have successfully completed a hygiene trajectory bedrijven to eliminate the virus. On another 16 farms, the virus got re-introduced.
In Denmark, the phrase “negative for PRRS” means that the animals have not been tested positive for virus antigens in their blood. After a hygiene trajectory, no vaccination will be needed using a modified live vaccine.
Older sows on a farm which have been going through an infection will still be seropositive. After a hygiene trajectory, altogether 20 PRRS naive gilts will be allowed to enter the sow facilities and they are being tested whether or not they can remain free from PRRS virus. Something similar happens 6 months later. As soon as that 2nd batch also proves to remain healthy, the farm will get the label “free from PRRS.” And after a while, the farm will cease to have any seropositive sows.
Regional approach to get PRRS under control
Denmark has been taking a regional approach to get PRRS under control. In the country’s 98 regions, there are 68 that include pigs. Late 2025, 23 regions had been declared free from PRRS, with 45 still having the virus.
The idea is, mid-2026, to obtain an official “PRRS-free” status for all regions that are without PRRS, which would be in line with EU regulation 2016/429. There will be sanctions when transporting pigs to PRRS-free regions – and the same will apply to disputable levels of biosecurity on farms.
Kees van Dooren
Source: pigprogress 05/01/2026
