Hunter New England Health (HNEH) recorded 708 COVID-19 cases in the latest update.

HNEH public health physician Dr David Durrheim said the state's testing capacity is "under enormous pressure".

He urged people to stay away from testing clinics unless they have COVID-19 symptoms, live in a household with a confirmed case or have been in a venue where NSW Health has specifically advised there has been high transmission.

There were 17 cases in Narrabri, four in Armidale and the Liverpool Plans, two in Gunnedah and one in Gwydir, Glen Innes and Tenterfield in the latest COVID-19 update on Thursday.

Tamworth recorded 39 new cases of the virus.

The double-digit increase in infection came after Tamworth broke records on Wednesday, with 47 new cases recorded in the highest number since the start of the pandemic.

Over 90 per cent of Tamworth residents are double-vaccinated against the virus, according to the latest update from NSW Health.

The state recorded 12,226 new cases in the 24 hours to 8pm on Wednesday, up from 11,201 in the previous 24-hour period. One person died with the virus.

There are 8159 active cases of the virus in the district, 25 of them in hospitals and one in an intensive care unit.

Dr Durrheim advised people to take a rapid antigen test (RAT) "before going out", particularly if socialising in a group, or going somewhere it may prove difficult to social distance.

Anyone who returns a positive RAT must get a PCR COVID-19 test to confirm the result," he said.

"We urge anyone who is yet to receive their vaccination to do so and if eligible book in for a booster or walk in today to vaccination hubs across the district," Durrheim said.

NSW Health advised people travelling to Queensland not to get a full PCR test in order to do so, because their results would not arrive back until after January 1 when rules change.