These are among the key reasons why Denmark introduced a national strategy in 2022 to reduce PRRS in Danish pig production. As part of this strategy, the Danish Agriculture & Food Council, Pig Sector, is working closely with a number of stakeholders to limit the spread of PRRS (Porcine Reproductive and Respiratory Syndrome). The aim is to reduce the number of PRRS-positive herds and improve the overall health status of Danish pig herds. 

The strategy is based on the principle that reducing the prevalence of PRRS requires a coordinated and targetted effort across the sector. Such an approach can improve health and animal welfare and, in turn, contribute to better financial results for pig producers. 

The results so far are encouraging: the coordinated efforts to reduce PRRS have paid off. 

What is PRRS and how is it controlled?

PRRS is a viral disease in pigs that can cause respiratory problems, abortions and premature farrowings. PRRS cannot infect humans and poses no risk to human health.

PRRS can spread through the air, which can make the disease difficult for individual pig producers to control, particularly in areas where other herds are infected. Regional, coordinated efforts are therefore essential to controlling and ultimately eliminating the disease. Achieving this requires a coordinated effort, with stakeholders across the sector working closely together.  

In some areas, it will be crucial for neighbouring herds to carry out eradication measures simultaneously and on as broad a scale as possible. This coordinated approach helps ensure that the infection is eliminated from the entire area and reduces the risk of  individual farms becoming reinfected after completing their own eradication efforts. Eradicating PRRS is a significant undertaking and the work is expected to continue over the years ahead.

“The Danish Agriculture & Food Council, Pig Sector has established a number of regional eradication councils. These bring together producers, veterinarians and other advisers to coordinate and plan regional efforts aimed at minimising the risk of reinfection,” says Sector Director Christian Fink Hansen.

While the strategy primarily relies on measures taken at herd level, Danish pig slaughterhouses also play an important role in reducing the prevalence of PRRS. For example, they have introduced a deduction in the settlement price for pigs from PRRS-virus-positive herds, providing producers with an added incentive to begin eradication efforts. 

Several areas in Denmark now PRRS-free

All of Denmark has now been divided into designated PRRS eradication regions. In 2025, Bornholm became the first region to be declared free of PRRS. The proportion of Danish pig herds with a negative PRRS health status rose to 74% in January 2026 and reached 75% in August 2026. At national level, the annual risk of infection for individual sows fell to 2.4%. PRRS type 2 remained the predominant type, both among PRRS-positive herds and among newly infected sow herds.

More recently, the Danish island of Lolland has also become free of PRRS. As a result, there are now no PRRS-positive herds in any of the municipalities covering Møn, Lolland and Falster. Together, these areas account for approximately 5% of Denmark’s total land area.

PRRS affects pigs worldwide, and Denmark’s efforts to reduce the prevalence of the disease are attracting considerable international interest. While PRRS poses no risk to humans, controlling the disease can improve production performance and animal welfare while reducing the need for antibiotics.