Nearly 100 people have been infected in an outbreak at two hospitals of the Norovirus, a highly contagious virus which causes diarrhoea and vomiting.
Eight wards have been closed at Royal Hampshire County Hospital
Eight wards have been closed and 60 patients have developed symptoms of the illness at the Royal Hampshire County Hospital in Winchester.
At St Mary's Hospital on the Isle of Wight three wards are affected and 33 patients are suffering with the virus.
Visitors have been asked to stay away in an attempt to control the outbreak.
Chris Evennett, chief executive at the Royal Hampshire County Hospital, said: "We are asking visitors to stay away this week.
"The sooner we can begin to get rid of the virus, the sooner we can get back to normal.
"I know that visits from friends and relatives brighten up a hospital stay but at the moment managing this infection is the priority."