The flu season has likely reached its peak in New South Wales, but people have been warned the worst is yet to come from a new wave of COVID-19.
Influenza cases have dropped, with hospitalisations of people with flu-like illness last week falling to 84 compared to 113 the week before, NSW Health said in its latest respiratory surveillance report.
"The recent trend in reported influenza cases suggests that the influenza season has peaked," the department said.
"However, there could be subsequent peaks given the early start to the 2022 influenza season."
Despite a drop in flu cases, the BA.4 and BA.5 Omicron sub-variants continue to rip through NSW.
There were 1,946 people in hospital with COVID in the state last week — an increase of more than 280 patients compared to the week before.
The BA.4 and BA.5 Omicron sub-variants have quickly become the dominant strain of the virus, now comprising 83 per cent of cases.
Chief Health Officer Kerry Chant earlier this week said the BA.4 and BA.5 sub-variants were "circulating widely in New South Wales".
"They are more able to evade immunity gained from previous infection and vaccination reinfection is more likely and possible just weeks after a prior infection," she said.
NSW Health has warned the worst was likely yet to come with the state's new COVID surge.
"The timing of the peak is likely to be sometime in late July or early August," the department said.
"(It) will depend on a combination of factors, including the growth advantage, immunity levels in the population, and environmental and behavioural factors (eg social mixing, mask-wearing, ventilation, isolation when unwell)."
Another Omicron sub-variant, BA.2.75, has recently emerged with three cases reported in returned travellers in NSW.
NSW Health said it was "monitoring the international situation" regarding the newest variant.
To reduce the risk of severe disease from all COVID sub-variants, the Australian Technical Advisory Group on Immunisation (ATAGI) has recommended a fourth dose of a COVID vaccine for people over 50, while those aged 30 to 49 may choose to have one.
In announcing the expansion of the COVID vaccination program, Health Minister Mark Butler said there was "a strong case" for older Australians to receive the additional booster shot but an "open question" about whether younger, healthy people needed it.