"Because they don't know they're infectious, there is the possibility of visitors putting staff and vulnerable patients at risk by removing their masks and getting too close to other people."
Hospital visitors are being asked to wear a properly fitted mask, wash and sanitise their hands regularly, and also keep their distance from other people as much as possible.
"The safety of patients and staff is our highest priority," Anstis said.
"Please be kind to our staff – they're doing their best to keep everyone safe."
Anstis said respiratory diseases like Covid-19, the flu and RSV can place a lot of pressure on hospitals – partly because large numbers of patients need care, and partly because staff catch the diseases and cannot work.
At various times this winter, some Tauranga and Whakatāne hospital departments had 10 per cent or more of their staff on sick leave while the hospitals are caring for large numbers of patients, she said.