01/03/2013 06:04 EST | Updated 03/05/2013 05:12 EST

Norovirus outbreaks contained at 2 Vancouver-area hospitals

One of two units affected by norovirus at New Westminster's Royal Columbian Hospital is expected to re-open today, but another ward at Vancouver General Hospital remains under containment.

Twelve patients and six staff members were affected after an outbreak shut down an entire floor of Royal Columbian Hospital on Wednesday.

"There is a new strain emerging this season and so we're seeing lots of norovirus in the community,” said Elizabeth Brodkin, medical director of infection control for the Fraser Health region.

One ward in Vancouver General Hospital's Centennial Pavilion is also under containment protocol after norovirus was detected there on Wednesday. Officials said it was not likely related to the outbreak in New Westminster.

Norovirus infections are characterized by a sudden onset of diarrhea and nausea. Symptoms usually last an average of 24 hours.

It can be transmitted from person to person via contaminated food or commonly touched surfaces, such as door handles and light switches.