People with the winter vomiting bug have been urged to remain off work for two days after their symptoms subside, because of the highly infectious nature of the virus.
The virus has affected hundreds of hospital patients and their relatives in counties such as Dublin, Sligo and Galway. Its symptoms include projectile vomiting, diarrhoea and abdominal pain.
While it is a short-lived illness, usually lasting not more than two days, the affected person remains infectious for a further two days.
Dr Paul McKeon, public health medicine specialist at the National Disease Surveillance Centre (NDSC), said people would spread the virus very easily if they returned to work or school or visited public places while still infectious.
Employers should not encourage staff to return to work too soon as the person would merely spread the virus among colleagues. Dr McKeon encouraged the public to read the NDSC advice on handling norovirus outbreaks such as the winter vomiting bug. The guidance is on the website www.ndsc.ie
The NDSC has advised people with the virus to telephone their GP if concerned, instead of calling to the surgery or to an accident and emergency department.
The situation worsened at both St James's and St Vincent's Hospitals yesterday. Some 71 patients are now affected by the virus in 11 wards at St Vincent's, while 52 staff are ill with it.
At St James's, 18 patients in five wards are affected, while 10 staff are suffering from the virus.
A spokesman for Beaumont Hospital said the bug appeared to be "well contained", with just one patient showing symptoms. One ward remains affected in Portiuncula Hospital in Galway. The authorities have urged the public to stay away from infected hospitals.
