Survival of pseudorabies virus on swabs maintained under standard field sample shipping conditions

Department of Food Animal and Equine Medicine, College of Veterinary Medicine, North Carolina State University, Raleigh, 27606, USA.

Pseudorabies virus survival was compared using three different types of applicator swabs in Eagle's minimum essential medium held under shipping conditions (packed with frozen gel packs) for up to 96 hours. Virus titer decay rates for dacron-tipped applicators were not statistically different from those of controls. Titer decay rates were statistically different from controls for cotton- and calcium alginate-tipped applicators. With the lowest input virus titer, virus was detectable up to 96, 72, or 24 hours after inoculation for dacron-, cotton-, and calcium alginate-tipped applicators, respectively. Dacron-tipped applicators were chosen to evaluate pseudorabies virus survival on tonsil swabs collected from experimentally challenged or contact control pigs to simulate field sampling and shipping conditions. Virus was still detectable in 20 of 24 swab samples after 72 hours in cell culture medium under shipping conditions.