Indirect Benefit

Reducing aerosol shedding of PRRS virus with MLV vaccine

Pigs raised in swine-dense areas are potentially at a greater risk of being infected with porcine reproductive and respiratory syndrome (PRRS) due to aerosol shedding of PRRS virus.1 Implementing strategies to reduce aerosol transmission of PRRS virus is important to reduce the shedding of PRRS virus within and between herds to minimize the risks of breaks or
re-breaks of herds.

Research has been conducted to evaluate shedding of wild type (wt) virus in pigs vaccinated with Ingelvac PRRS® as compared to non-vaccinates.2,3,4 A recent study evaluated both the duration and frequency of aerosol shedding in pigs infected with PRRSv 29 days following vaccination with Ingelvac PRRS® compared to non-vaccinated pigs.4 The period between the first and last positive aerosol samples was 36 days for the non-vaccinated barn, and only 6 days for the vaccinated barn. Additionally, the total number of positive sampling days during the 118-day trial was 21 for the non-vaccinated barn and only 4 days for the vaccinated barn (see below).

The barn with pigs vaccinated with Ingelvac PRRS® had 17 fewer positive aerosol days and 30 days’ shorter total shedding period compared to the non-vaccinated barn.

Reducing both the duration and frequency at which infected pigs shed wt PRRS virus can help minimize the chances of aerosol spread of the virus within a region. Talk to your Boehringer Ingelheim Vetmedica, Inc. representative to discuss how Ingelvac PRRS® vaccines can help your herd.

References
  1. Mortensen S, Stryhn H, Søgaard R, et al. Risk factors for infection of sow herds with porcine reproductive and respiratory syndrome (PRRS) virus. Prev Vet Med 2002;53(1–2):83–101.
  2. Cano JP, Dee SA, Murtaugh MP, Pijoan C. Impact of a modified-live porcine reproductive and respiratory syndrome virus vaccine intervention on a population of pigs infected with a heterologous isolate. Vaccine 2007;25(22):4382–4391.
  3. Linhares DC, Cano JP, Wetzell T, et al. Effect of modified-live porcine reproductive and respiratory syndrome virus (PRRSv) vaccine on the shedding of wild-type virus from an infected population of growing pigs. Vaccine 2012;30(2):407–413.
  4. Wetzell T, Cano J, Rustvold J. Reduction of Wild-Type PRRS Virus Shedding in Aerosol of Growing Pigs by Modified-Live Virus Vaccination at Weaning. 2013 Pipestone Research Committee, Leman Conference, p. 196.