The Hunter is facing a big influenza wave this winter, while two other viruses that target children have made an ominous return.
Bad cases of RSV [respiratory syncytial virus] in the Hunter New England health district quadrupled to 383 in February and 614 in March, when compared to the same months last year.
The NSW Respiratory Surveillance Report, released on Thursday, said "RSV activity remains at high levels".
This included emergency department presentations and hospital admissions for children aged 0-4 with bronchiolitis, which is mainly caused by RSV.
Dr David Durrheim, a Hunter public health physician, said RSV and whooping cough had "bounced back" with "big increases".
"They're behaving very much like they did prior to the pandemic. The possibility of influenza responding the same way is very real."
Influenza cases, now at low levels, are expected to soar in winter.
"We should probably prepare ourselves for a sizeable influenza wave," Dr Durrheim said.
"The flu vaccine is now available, broadly through general practices, aged-care facilities and pharmacies."
Flu cases in Hunter New England hit monthly highs last year of 2003 [July], 1770 [June], 1049 [August] and 793 [May].
The district's highest monthly flu cases since 2012 were 9101 in June 2022, far higher than the 5878 in August 2017.
The figures refer to people unwell enough to seek medical attention and take a PCR test.
ATAGI [Australian Technical Advisory Group on Immunisation] recommends the influenza vaccine for all people aged six months and over.
It said an annual vaccination was "the most important way to prevent influenza and its complications", which include ear and sinus infections, pneumonia and sepsis.
"While protection is generally expected to last throughout the year, the highest level of protection occurs in the first three to four months after vaccination," it stated.
An RSV vaccine for pregnant mums, approved by the TGA last month, is expected to be available next year.
This will enable mums to transmit antibodies to their babies, protecting them in the first few months of life. This vaccination method has occurred in NSW for whooping cough since 2015.
Meanwhile, data released on Thursday showed 146 PCR-confirmed COVID cases in Hunter New England in the week to April 13.
The district recorded 616 COVID cases in March, compared to 4074 in the same month last year.
"COVID is at low levels at the moment, which is fantastic," Dr Durrheim said.
The district had 39 people with COVID in hospital, with one in ICU, and 14 aged-care outbreaks.
"The patterns with COVID are that we always get a winter wave, and we're also getting a summer wave."
The latest data showed 10.6 per cent of Hunter residents aged 18 and over had a COVID vaccination in the last six months. This rose from 9.9 per cent in March.
Dr Durrheim urged people to consider a booster if they had not had a COVID infection or jab in the last six months.
"When they roll up their sleeves for their influenza booster, it's a good idea to get a COVID booster as well," he said.
"You can get the two at the same time, one in each arm."
New research from RMIT University and Monash University found COVID vaccines prevented the death of 17,760 people aged 50 and over in NSW from August 2021 to July 2022.
The death rate in unvaccinated people aged 50 and over was 7.7 times higher than those double vaccinated, and 11.2 times higher than those who received a booster.
