Evaluation of internal farm biosecurity measures combined with sow vaccination to prevent influenza A virus infection in groups of due-to-wean pigs

Reprinted as posted on Swine in Minnesota blog November 29, 2022.

Recently Montse Torremorell’s lab published a paper regarding the impact that internal biosecurity measures can have on influenza A infection in piglets when combined with sow vaccination.

Methods

• Six Midwestern farrow-to-wean farms, positive for swine influenza. No vaccination in the six months prior.
• Five farms used biosecurity measures and whole herd vaccination. One served as control.
• Added internal biosecurity included stopping piglet movement after day 3 and no nurse sow and switching of equipment between litters for example.
• All sows and gilts received two IM injections of farm-specific autogenous influenza vaccine.
• Thirty udder wipes were collected for three weeks (90 udder wipes total), starting six weeks after the second vaccination.
• Environmental samples were collected each week as well.

Results

Following these interventions, four of the five treatment farms had significant reductions in Influenza A Virus (IAV) detection (p-value < 0.05). Three of the farms tested negative at all sampling points post-intervention and one farm had a 21% reduction in IAV positivity.

Conclusion

This study indicates that a protocol that combines sow vaccination and enhanced biosecurity practices may limit IAV transmission among piglets and enable the weaning of groups of pigs free from the virus.

The full article is available in open access on the Vet Research journal’s website.