Cost-benefit analysis of swine influenza a vaccination in wean-to-finish production setting in the United States.

Abstract

Swine influenza virus A (SIV-A) is endemic in hog farms globally, causing significant economic losses to the swine industry. While vaccination is a recommended control strategy, its economic value in specific production phases remains under-evaluated. This study investigated the economic viability of SIV-A vaccination in a U.S. wean-to-finish commercial farm using a stochastic epidemic model. A cost-benefit analysis was performed to estimate the Benefit-Cost Ratio (BCR), Net Present Value (NPV), and Return on Investment (ROI) of swine vaccination. In the absence of vaccination, the model predicted a high within-farm attack rate of approximately 82.5 % (95 % Confidence Interval (CI): 81 % - 0.84 %). Economic analysis showed that the profitability of SIV-A vaccination was highly dependent on vaccine efficacy. Vaccine efficacy below 70 % was shown to be not economically viable, yielding negative NPV and BCR below 1. Conversely, vaccination with ≥ 80 % efficacy was profitable, with BCRs ranging from 1.54 (95 % CI: 1.538, 1.54) to 4.09 (95 % CI: 4.082, 4.092) and net profits varying from US$0.90 ( 95 % CI: US$0.79, US$1.02) per pig up to US$3.41 (95 %CI: US$3.40, US$3.41) per pig. Vaccination against SIV-A in wean-to-finish settings was shown to be an economically favorable intervention when the vaccine is highly efficacious against the circulating SIV-A subtype. Sensitivity analysis indicated that vaccine efficacy, the cost of vaccination, and influenza-induced mortality rates were the most critical drivers determining the economic success of the program.