The question that is most likely going to point the vet to the reason for the reinfection is "Did the new pigs come into contact with materials with which the dead pigs may have infected?"
Pseudorabies is an infection caused by herpes virus and is common in pigs. The disease spreads very fast since it primary spreads by contact with infected animals making it an infectious or contagious disease.
The first question that the vet should ask in order to ascertain the reason for the reinfection is; "Did the new pigs come into contact with materials with which the dead pigs may have infected?"
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