SEROPREVALENCE OF H3N2 INFLUENZA A VIRUS IN PIGS FROM PARANÁ (SOUTH BRAZIL): INTERFERENCE OF THE ANIMAL MANAGEMENT AND CLIMATIC CONDITIONS

Since the beginning of the 20th Century, Influenza can be understood as an illness associated to a viral infection, and its etiological agent can be better characterized. From then on, the swine species has occupied a prominent place in the Influenza epidemiology, for it allows the circulation and replication of viruses of potentially human and avian origin. The aim of the present study was to determine the current seroprevalence for the H3N2 virus subtype in two types of pig-raising systems in the state of Parana-Brazil. The first one represents pig farms, with an adequate health, nutritional, and environmental management; and the second one represents pig runs, without an adequate health, nutritional, and environmental management. To accomplish these aims, 675 blood samples of pigs were analyzed by HI (hemagglutination inhibition) assay and the interference of the pig management and climatic conditions of each region were analyzed. The results showed that 46% of the pig farms are positive, as opposed to 6% of the pig runs; and 20% of the animals on pig farms are serum positive, as opposed to 3% of the animals in pig runs. Likewise, the samples coming from colder areas in Parana presented, as a rule, a high positivity index. The results allow concluding that the virus is present in pig-raising facilities, and the strategies for preventing future epidemics and epizooties must consider the role of swine as an important factor in the epidemiology of influenza. DOI:  http://dx.doi.org/10.17525/vrr.v15i1.36