Original Scientific Article
Swine influenza А virus (swIAV) seroprevalence in Macedonian commercial farrow-to-finish pig farms
Branko Angjelovski * ,
Miroslav Kjosevski ,
Aleksandar Janevski ,
Jovan A. Bojkovski ,
Aleksandar Dodovski

Mac Vet Rev 2025; 48 (2): i - ix

10.2478/macvetrev-2025-0025

Received: 20 February 2025

Received in revised form: 17 April 2025

Accepted: 02 June 2025

Available Online First: 24 July 2025

Published on: 15 October 2025

Correspondence: Branko Angjelovski, brankoa@fvm.ukim.edu.mk
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Abstract

Swine influenza caused by the influenza A virus significantly affects pig production and pig health due to acute respiratory disease and huge economic losses. Pigs play an essential role in the epidemiology of influenza because they act as a mixing vessel for the formation of potentially pandemic zoonotic strains. The objective of our study was to assess the seroprevalence of Swine influenza A viruses (swIAV) in commercial pig farms in Macedonia. A total of 373 blood samples were collected from piglets aged 1 to 4 weeks of sows with different parities from 19 different commercial farrow-to-finish pig farms. For the detection of anti-IAV antibodies, sera samples were analyzed using a competitive ELISA. All farms were seropositive to swIAV. Seropositivity was detected in 258 (69.2%) samples, ranging between 10 and 100% at farm level. The highest seroprevalence was found in piglets from sows in the 5-6th parity. In contrast, the lowest seropositivity was found in samples from the youngest sows (1-2nd parity), which indicates that the virus has circulated for a longer period in these farms. Furthermore, large farms with more than 120 sows had a significantly greater percentage of seropositive animals than small farms with less than 120 breeding sows (83% vs. 54%, respectively). In conclusion, our results demonstrated that swIAV circulates endemically in Macedonian commercial farrow-to-finish pig farms, underscoring the need of immunization in preventing infection on these farms.

Keywords: Swine influenza A virus, seroprevalence, pigs, commercial farms, Macedonian

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Copyright

© 2025 Angjelovski B. This is an open-access article published under the terms of the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Conflict of Interest Statement

The authors have declared that no competing interests exist.

Citation Information

Macedonian Veterinary Review. Volume 48, Issue 2, Pages i-ix, e-ISSN 1857-7415, p-ISSN 1409-7621, DOI: https://doi.org/10.2478/macvetrev-2025-0025 

The all content of the Macedonian Veterinary Review, except where otherwise noted, is licensed under a Creative Commons Attribution License.