The Victoria care home at the centre of a deadly norovirus outbreak has done all it can to prevent the spread of the disease, according to the chief medical health officer for Vancouver Island.


The deaths of nine elderly residents at the Selkirk Place care facility have been linked to the gastrointestinal virus since the outbreak started three weeks ago .


The region's chief medical health officer Dr. Richard Stanwick has been working closely with the care home to manage the outbreak, which infected 100 patients and 50 staff.


"We have a 16-page protocol. They have followed all of the protocols we have established," said Stanwick.


Selkirk Place has undertaken constant cleaning, quarantining anyone who shows any symptoms, preventing inside and outside visits and monitoring everyone very closely.


Despite this, Stanwick said he's not surprised at the number of deaths.


"These are highly vulnerable, fragile people who are being successfully nursed through this event.


"And while nine did succumb, I think that the remainder of the population, it really is a testimony to the staff and to these people, that we've been able to hold it to this point."


Stanwick says 11 people remain on the sick list, and the facility will not be open to the public until it has gone for 48 hours without any new cases.


Norovirus — once known as Norwalk virus — is highly contagious and often spreads in places like schools, cruise ships and nursing homes. The gastrointestinal virus causes bouts of vomiting and diarrhea which can last for a few days.


A new strain of the virus evolves every two or three years; the latest was identified earlier this year and is known as the Sydney strain.


There are no drugs to treat norovirus itself, although it is important to drink lots of fluids to guard against dehydration. It is possible to help stop the spread of the virus by cleaning affected environments and washing hands and food thoroughly.