Abstract:

The novel swine-origin influenza A(H1N1) virus can cause respiratory infectious diseases in humans and pigs, it attracts wide attention and research since its worldwide outbreak in April 2009. This study researched the airborne spread characteristics of the virus. In January 2011, a swine-origin H1N1 epidemic emerged in eastern China, one novel swine-origin influenza A(H1N1) virus A/swine/Shandong/07/2011 was isolated from throat swab samples and lung collected from swine. Quantitative reverse transcription polymerase chain reaction (RT-qPCR) was used to detect viruses in air samples taken from inside and outside of piggeries; Aerosol transmission model were also established to analyze the airborne transmission characteristics in the experimental conditions of novel swine-origin influenza A (H1N1) virus. The detected rate of virus in piggeries air samples was 26.10% and was shown to contain 3.14-5.72 log₁₀ copies·m^－3 air of virus. The rate virus detected in 10 m downwind of piggeries air samples was 40.70% and was shown to contain 2.24-3.77 log₁₀ copies·m^-3 air of virus. In the model, this virus was capable of forming aerosols and infecting animals in aerosol exposure group by transfer of aerosols, although infection by aerosols was found to be less efficient than by direct contact. This study demonstrates that this SO 2009（H1N1）IV strain is able to be aerosolized by infected animals and to be transmitted to susceptible animals by airborne routes in the experimental conditions.

Key words: novel swine-origin influenza A(H1N1) virus, quantitative reverse transcription polymerase chain reaction (RT-qPCR), viral aerosols, aerosol transmission model