Can gastroenteritis viruses spread by air?

Noroviruses are single stranded RNA viruses belonging to the Caliciviridae family. They are the causative organisms for at least 50% of gastroenteritis outbreaks all over the world. Infection can occur via multiple routes like direct contact with a patient, exposure to infected feces or vomitus and contact with contaminated surfaces. Although it usually spreads via faecal-oral route, aerosols of the virus, if inhaled, settle in the pharynx. These can later be swallowed.

Transmission electron micrograph of Norwalk virus. Norwalk virus (classified under Norovirus genus) electron micrograph.

Recently, researchers at the Université Laval, Québec, Canada conducted a study to determine whether noroviruses can get aerosolized during gastroenteritis outbreaks in healthcare facilities. 48 air samples were taken from 8 hospitals. Samples were taken at various locations – 1m away from the patient, outside the the patient’s room and at the nursing station. Norovirus genomes were found in the air samples collected from 6 of the 8 hospitals in the study. The concentrations of the virus ranged from 1.35×101 to 2.35×103 genomes per m3 in 47% of air samples. The aerosolized virus was found to preserve its infectivity and integrity during in vitro aerosol studies.

Source : Clinical Infectious Diseases, 2015 Apr 21. pii: civ321. via http://www.ncbi.nlm.nih.gov/pubmed/25900175