Flu cases are exploding and Australia is now in its fifth wave of COVID-19, as viruses hit schools, child care centres and workplaces around the Illawarra.
Health authorities are urging people to get vaccinated with both the flu shot and any COVID boosters as winter looms next week.
The latest Respiratory Surveillance showed a 66 per cent increase in the number of influenza cases in the last week, with more than 2131 cases across the state.
In the Illawarra, there were 88 cases of the flu reported, and 762 cases of COVID - which is down on last weeks total.
But NSW Chief Health Officer Dr Kerry Chant said the notifications of COVID cases recorded were well below the actual numbers.
"COVID spread remains high in the community," she said.
"We know that those notifications are really an underestimate of activity, so there's many more people infected than then reflected in that notification data."
Health Minister Ryan Park said staying up to date with recommended vaccinations was the best way people could protect themselves, their family and the community from serious illness.
"Influenza is a serious disease in young children, and both COVID-19 and influenza viruses can have serious consequences for older adults, people who have chronic health conditions and those who are immunocompromised," Mr Park said.
"Vaccination remains the best protection against severe illness and now is the time to make sure you are up to date with the shots recommended for you."
Dr Chant said the state was anticipating high levels of influenza activity over the coming weeks and months, and said vaccination level needed to rise.
"Our influenza coverage rates for children six months to less than five years, as at the 21st of May, were 13.5%," she said.
"That's an improvement on what they were at the same time last year, but we're really aiming to see them well into to 30% and over the next few years, I really would aim to work with the community and parents and carers to get those up around 60%."
"Influenza does hit this age group hard."
She said about 49 per cent of over 65s was at 49 per cent.
"We do need to get that vaccination higher," she said.
"There is plenty of stock of COVID-19 and influenza vaccines available at pharmacies and GPs, so please book in today.
"We know there are high levels of COVID-19 circulating in the community and with a rapid increase of influenza cases this week, it is also important people continue to take simple precautions to protect themselves and each other."
Those considered to be at higher risk of severe illness from influenza are eligible for a free influenza vaccine and include children aged six months to under five years, people aged 65 and over, Aboriginal people, pregnant women and those with serious health conditions such as diabetes, cancer, immune disorders, obesity, severe asthma, kidney, heart, lung or liver disease.
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