Comparison of Bioaerosol Samplers and Media for the Collection of Aerosolized Norovirus

摘要

The United States (US) has an estimated 179 million cases of acute gastroenteritis (AGE) each year. Of the total cases of AGE more than 39 million are caused be an infectious agent, such as bacteria and virus. One of the most common infectious agents that result in AGE (iAGE) is norovirus. Norovirus causes greater than 90% of iAGE outbreaks, and results in 56,000-71,000 hospitalizations in the US each year. Route of transmission is known to occur by direct and indirect contact with contaminated surfaces; however, evidence has suggested that the virus can be transmitted via aerosol. Determining routes of exposure is important as the infectious dose for norovirus has been reported as low as 10 virions. Little research has been performed measuring aerosolized norovirus in the field and laboratory, which may be a significant route of transmission. Therefore, a developed methodology is needed for norovirus aerosol sampling so that inhalation exposure to norovirus can be determined. This study compared two samplers and two liquid sampling medias in the collection of airborne norovirus. The SKC BioSampler and NIOSH Bioaerosol sampler containing either Phosphate-Buffered Saline or Hanks Balanced Salt Solution were compared for collection of murine norovirus (MNV:CW3). Ten 30-minute trials were completed by aerosolizing MNV:CW3 in a laboratory bioaerosol chamber to compare concentrations of norovirus collected across two types of bioaerosol samplers using two liquid sampling medias. Samples were analyzed using RT-qPCR, as well as PMA:RT-qPCR to evaluate virus capsid integrity. The mean total virus particles per cubic meter of sampled air were compared between samplers and liquid sampling medias. Preliminary results (n=40) indicate no difference between media type, however there was a difference between the percentage of virus with intact capsids before and after sampling. Future investigations targeting aerosolized norovirus can incorporate the findings of this study.