Influenza A virus in swine (IAV-S).

Widespread impact on productivity and profitability

Influenza A virus in swine (IAV-S) can affect > 70% of growing pigs each year and can  lead to major economic consequences1,2

Uncomplicated IAV-S leads to an estimated loss of more than $3 per pig; when IAV-S is present with concurrent infections, the loss can be greater than $10 per pig

IAV-S is one of the top 3 diseases affecting pigs in all phases of production

An ongoing threat to the entire operation

  • Uncomplicated IAV-S infection is a relatively short disease process4 
    • In contemporary swine operations, however, the disease can linger for a prolonged period as it continues to find susceptible animals5
  • Transmission is direct via pig-to-pig or droplet transmission route6
  • IAV-S can be endemic in large populations, even in all-in, all-out operations6,7
  • As an RNA virus, IAV-S can change and adapt over time,8 necessitating a vaccine solution with broader capabilities to cross-protect
  • The threat of IAV-S goes beyond endemic sow herds. Growing pigs, with limited time for protection, are at particular risk (eg, during weaning and commingling)9
     

*Adapted from Detmer et al.10

IAV-S can spread by direct transmission through all production phases

1. USDA, APHIS, VS, NAHMS. Swine 2012 Part II: Reference of swine health and health management in the United States, 2012. February 2016.

2. Dykhuis Haden C, Painter T,  Fangman T, Holtkamp D. Assessing production parameters and economic impact of swine in influenza, PRRS and Mycoplasma hyopneumoniae on finishing pigs in a large production system. In: Proceedings of the 43rd American Association of Swine Veterinarians Annual Meeting; March 10–13, 2012; Denver, CO: 75–76.

3. Vincent AL, Perez DR, Rajao D, et al. Influenza A virus vaccines for swine. Vet Microbiol. 2016;206:35–44. doi:10.1016/j.vetmic.2016.11.026. Epub 2016 Nov 24.

4. Van Reeth K, Brown IH, Olsen CW. Influenza virus. In: Zimmerman JJ, Karriker LA, Ramirez A, Schwartz KJ, Stevenson GW, eds. Diseases of Swine. 10th ed. West Sussex, UK: Wiley-Blackwell; 2012:557–571.

5. Pitzer VE, Aguas R, Riley S, Loeffen WLA, Wood JLN, Grenfell BT. High turnover drives prolonged persistence of influenza in managed pig herds. J R Soc Interface. 2016;13:20160138. doi:10.1098/rsif.2016.0138.

6. Brown IH. The epidemiology and evolution of influenza viruses in pigs. Vet Microbiol. 2000;74:29–46.

7. Torremorell M, Juarez A, Chavez E, Yescas J, Doporto JM, Gramer M. Procedures to eliminate H3N2 swine influenza virus from a pig herd. Vet Rec. 2009;165(3):74–77.

8. Lewis NS, Russell CA, Langat P, et al. The global antigenic diversity of swine influenza A viruses. elifesciences.org. 2016;5:e12217.

9. Alvarez J, Sarradell J, Kerkaert B, et al. Association of the presence of influenza A virus and porcine reproductive and respiratory syndrome virus in sow farms with post-weaning mortality. Prev Vet Med. 2015;121:240–245.

10. Detmer S, Gramer M, Goyal S, Torremorell M, Torrison J. Diagnostics and surveillance for swine influenza. Curr Top Microbiol Immunol. 2013;370:85—112. doi:10.1007/82_2012_220.