Control of Influenza A Virus in Swine Calls for Whole-Herd Approach
Influenza A virus in swine (IAV-S) is considered to be one of the top 3 diseases threatening productivity in swine herds. IAV-S is hard to control on many farms because it can become endemic from the continuous birth and subsequent exposure of naïve piglets to resident IAV-S or as a result of the arrival of replacement female pigs with new IAV-S.1-4
A whole-herd approach (WHA) has been used successfully as a key strategic approach to controlling porcine reproductive and respiratory syndrome (PRRS) virus infection within a population.5 The goal of WHA is to minimize exposure and maximize immunity of susceptible pigs.6 This approach is equally appropriate for IAV-S and can lead to the reduction or elimination of IAV-S endemicity and the impact of IAV-S in young pigs.
Current IAV-S control
Even with homology of circulating strains, an approach that relies on killed vaccines to protect piglets through the transfer of maternal antibodies offers limited control of IAV-S. Current sow vaccination practices generally fail to control IAV-S transmission and can actually prolong the transmission period. As a result, endemic disease will persist because of continuous circulating IAV-S among young animals.7
Additionally, because transmission continues to be a factor, a control program that depends on vaccination solely of sows does not help to control either antigenic drift or IAV-S diversity.7
Why a whole-herd approach?
WHA aims to target the key at-risk populations primarily responsible for IAV-S transmission and circulation (farrowing units, the gilt development unit, and breeding and gestation barns). WHA leverages practices that decrease young pigs’ exposure to IAV-S, maximize their immunity to IAV-S, and limit the ability of new strains of IAV-S to enter the herd.4,8-10
Implementation of WHA takes advantage of the fact that pigs are born free of IAV-S (ie, there is no vertical transmission from the sow).11 It is imperative to capitalize on this opportunity by creating a window in which these young, naïve pigs can be given a strong foundation for IAV-S control. This control is achieved by following practices that minimize the IAV-S challenge in the farrowing house while simultaneously building broad immunity in the young pig.
Ingelvac Provenza® fits in a whole-herd approach
As an intranasal, live attenuated influenza vaccine for neonatal pigs, Ingelvac Provenza stimulates local mucosal immunity, offering protection at the site of natural IAV-S infection. Ingelvac Provenza provides broad cross-protection against the ever-evolving risk of IAV-S, through the nursery period and beyond.12-14 Only Ingelvac Provenza protects the right animal, at the right time, by the right route—making it the ideal tool to use as part of a WHA.
For more information about WHA for IAV-S control, talk to your Boehringer Ingelheim representative or visit IngelvacProvenza.com.