Enzyme-linked immunosorbent assay detection of antibodies against swine influenza virus in western Romania

Swine influenza, a respiratory disease that affects pigs of all ages, is caused by type A influenza virus.1 Morbidity rates can reach 100%, while mortality rates are generally low. Subtypes of swine influenza virus (SIV) most frequently identified in pigs include classical and avian H1N1, reassortant (r) H3N2, and rH1N2. In Europe, three main influenza A subtypes (H1N1, H1N2, H3N2) circulate in swine populations.2 The H1N1 and H3N2 subtypes have been enzootic in several swine-producing countries in Europe for more than 20 years.3-5 Surveillance and serological monitoring of influenza in swine populations is essential for adequate control and diagnosis of infection.4 Swine influenza viruses are infectious to people as zoonotic agents. Zoonotic infections have been documented in the United States, Europe, New Zealand, and Hong Kong, in some cases resulting in the death of the people infected.6