Evidence for airborne transmission of Norwalk-like virus (NLV) in a hotel restaurant

An outbreak of gastroenteritis followed a meal in a large hotel during whic h one of the diners vomited. The clinical features of the illness suggested Norwalk-like virus (NLV, small round structured virus) infection, and this was confirmed by electron microscopy and reverse transcriptase polymerase chain reaction (RT-PCR) of stool samples. Further characterization of the v irus by nucleotide sequence analysis of the PCR amplicons revealed identica l strains in all the affected individuals. The foods served at the meal cou ld not be demonstrated to be the cause of the outbreak, Analysis of attack rates by dining table showed an inverse relationship with the distance from the parson who vomited. No one eating in a separate restaurant reported il lness. Transmission from person-to-person or direct contamination of food s eems unlikely in this outbreak. However, the findings are consistent with a irborne spread of NLV with infection by inhalation with subsequent ingestio n of virus particles.