More patients at Raigmore Hospital in Inverness have gone down with the flu virus.
Two more patients in the ward that has been closed to new admissions have contracted the illness, bringing the total to 10.
Ward 7C – which treats people with the renal and gastrointestinal conditions – was closed on Tuesday after eight patients developed seasonal flu.
An NHS Highland spokeswoman said two more patients were affected, but no staff in the 34-bed ward have been affected by the outbreak.
There were 33 patients in the ward when it was closed to new admissions, but the spokeswoman said this number had reduced to 25 due to discharges.
Relatives and friends of the remaining patients are asked not to visit if at all possible and to telephone the nurse in charge before travelling to the hospital.
The 400-bed hospital, which was on red alert due to a shortage of beds on Monday, is still struggling to keep up with demand due to “winter pressures”.
Regular bed assessments result in a grading of red, amber or green, depending on the pressure on the available beds and the situation today was classified as “amber plus”.
The health board spokeswoman said 10 planned non-emergency operations and day case procedures were cancelled today, but none have so far been cancelled for tomorrow.
Highlands and Islands Scottish Labour MSP Rhoda Grant has called for everyone to play their part in helping NHS Highland cope with the flu outbreak.
She said: “Most importantly, people who are eligible for the flu vaccine should take up this opportunity to get it as soon as possible.
“This not only protects them, but it also slows down the spread of the virus amongst family, friends and work colleagues.”
Mrs Grant added that flu could be extremely dangerous for people with health conditions that lower immunity or lead to breathing problems.
She said: “The NHS is already under great strain due to under-funding, but if we follow the advice from NHS Highland we can all help get the health service through this testing time.”
Relatives and friends who want to contact Ward 7C should call the hospital switchboard on 01463 704000.