Chief health officer Dr Kerry Chant said flu cases were escalating quickly, with 7,000 reported during May, and 1,140 in the past week alone.
"We strongly urge everyone over six months of age to get a flu shot as soon as possible to protect themselves and their loved ones, as the virus is easily spread and potentially deadly"
"This is particularly important for those in high-risk groups, such as the elderly and children aged six months to five years. If you live in an aged or disability care facility, are aged over 65 or are immunocompromised, now is the time to book in," Dr Chant said.
NSW Health are urging those who are eligible to get a Covid winter booster as well as the flu vaccine at the same time.
Pharmacies will be able to administer flu vaccines to children five and up, reduced from 10 to allow families to get vaccinated together.
Previously the influenza vaccine was only subsidised for high-risk groups.
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