A study, published in the Journal of Hospital Infection, examined the clinical, ward and genotype risk factors for norovirus hospital outbreaks.
Researchers collected clinical data, ward setting and norovirus genotype from 65 norovirus-positive index cases in outbreaks and 186 sporadic norovirus cases at 192 wards in Sweden. The study period spanned 2010 to 2012.
The study shows that the norovirus outbreaks were independently associated with:
• The number of patients sharing room with the norovirus case
• Vomiting
• Age (more than 80 years)
• Comorbidity
• Onset of symptoms after admission to the ward
A univariable analysis showed infection with genotype GII.4 was strongly associated with norovirus outbreak.
"Recognition of these factors may help direct and prioritize infection control actions based on the outbreak risk," study authors concluded.