Two residential-care wings at Strathallan Lifecare have been locked down due to an outbreak of an "as-yet-unidentified" virus.
The rest home became aware of the virus two weeks ago.
Strathallan Lifecare is one of two South Canterbury rest homes affected by outbreaks of diarrhoea and vomiting, but Community and Public Health would not confirm which other home was affected.
Timaru's Community and Public Health health protection officer, Ed Bennett, said the details of rest homes involved in outbreaks were not usually publicised.
"Staff, residents and visitors to the affected rest homes will already be aware of the situation and the rest homes concerned are co-operating with our staff to investigate and control these outbreaks."
The general manager at Strathallan Lifecare, Debbie McMaster, said 15 people had been affected by the virus, including residents and staff. Specimens have been taken to identify the causative organism.
Anyone intending to visit Strathallan should stay away.
"We are advising people not to visit for their own protection and to reduce the risk of spread. This is best practice in all infectious situations.
"We want to reduce the spread of infection both in-house and in the community."
No-one can visit until the rest home is symptom-clear for at least 48 hours.
Bennett said the virus in question could be norovirus.
Rest homes are provided with guidelines covering a range of control precautions such as hand hygiene, washing and cleaning, patient movement, isolation and visitor control.
Norovirus outbreaks in institutions such as rest homes are comparatively common, Bennett said, and symptoms for each person last about 24 to 48 hours.
Older people are more vulnerable to the complications of infection with norovirus.
Norovirus is highly infectious and spreads very readily. It takes only one unwell person to affect many others.
- The Timaru Herald