It is has been proven that the PRRS virus can spread by direct contact of infected pigs with non-infected pigs. But there is also speculation that the PRRS virus can spread from indirect contact, such as by fomites, biological and mechanical vectors and by aerosols. Although tests done on indirect transmission haven’t produced clear results, but if it is a threat producers will have to improve there biosecurity guards to adapt. An ongoing study for virus surveillance was going on at the National Animal Disease Center with animals suspected to have the PRRS virus. These animals had their blood samples taken when the appeared to be infected with the virus. They consisted of 7 different herds, 6 of which were in close proximity to each other. Each herd was given a ranking in order of when they contacted the virus. 6 farms tested had the same isolate pattern while one had a unique isolate pattern. The farmers revealed in their interviews that they did not share equipment, their deads did not contact each other, and only one site had a vet visit in the previous 6 months. Only one herd was kept in a complete confinement system, while the others were in an open faced facility. The similarity of the PRRS virus found in all but seven of the farms was believed to be because of use of replacement animals from the same herd or the use of contaminated semen, not by indirect contact. The one herd that did not have the same strain of virus may have been because the virus made rapid mutations when it entered that specific farm that were different from the changes the other viruses went through. This research supports the hypothesis that PRRS area spread may occur but the method is unknown. When producers are building new facilities and deciding where to build them, PRRS virus area spreading should be considered.