Now a hospital in Melbourne, Australia, has isolated seven patients in a bid to contain an outbreak of gastroenteritis.
Health authorities confirmed last night that an entire ward at the Monash Medical Centre in Clayton had been closed off as tests were conducted to identify the viral strain responsible.
The city's latest winter-illness outbreak comes as disease experts warn that a new and highly virulent strain of gastroenteritis could afflict tens of thousands of Australians in the next few months.
As hospitals around the country shake off a recent spike in cases of influenza A, researchers from the University of New South Wales (NSW) predict that a new strain of noro virus will cause a second-wave illness.
"The first evidence of this was about three weeks ago. That's when we had simultaneous clusters in multiple states," said virologist Peter White.
The new strain, called 2006b noro virus, is a mutation of the bug seen in Australia last year and has already passed through Europe.
Dr White said the arrival of a noro virus outbreak was unexpected, given that there was a global epidemic of the illness just last year.
"We normally see a noro virus epidemic every two years, so we weren't expecting an outbreak until next year," he said.
Noro virus causes symptoms such as nausea, vomiting and diarrhoea. Illness typically lasts for three days.
Although noro virus has already been confirmed as the cause of recent gastro clusters in Queensland, Adelaide and NSW, it was too early last night to tell whether it had caused the outbreak at Monash Clayton.
The Victorian Department of Human Services did confirm late yesterday, however, that the 2006b strain was responsible for a recent "elevation in notifications" of noro virus and other viral illness.
"We've seen elevated levels of gastro around the place," DHS spokesman Bram Alexander said. "This is in settings such as aged care, nursing homes and child-care centres."
It is believed noro virus was responsible for the gastro outbreak at the San Carlo Home for the Aged in Melbourne earlier this month.
Almost 50 staff and residents of the South Morang home were struck down with gastro, and the death of a 94-year-old man is still being investigated.
Other hospitals around Melbourne said they had experienced a recent increase in gastro-like illness, though none has identified the noro virus as being responsible.