* Coronavirus is continuing to spread in Sydney's west as NSW records four new locally acquired COVID-19 cases in the 24 hours to 8pm on Tuesday, including an 18-year-old man whose positive result had previously been reported by authorities.

* Several regional NSW communities are on high alert after a teenager who visited Orange, Nyngan and Broken Hill tested positive, in connection with the BWS Berala cluster.

* That cluster is under urgent investigation after a woman who visited the Woolworths next door - but not BWS - picked up the virus. Woolworths customers between December 20 and 31 now all need to be tested.

* The northern beaches Avalon cluster has risen to 149 after a man in his 20s who is a household contact of an Avalon case tested positive.

* Testing numbers were up to 32,667 from 26,391 the previous day

* Authorities are concerned there may be unrecognised chains of transmission through western Sydney.

* NSW authorities have expanded the western Sydney suburbs whose residents and workers are locked out of attending the Australia-India cricket Test at the SCG from Thursday.

* Those who go to the SCG need to wear a mask at all times except when eating and drinking.

* In Victoria cricket fans and Boxing Day shoppers are being asked to get tested and self-isolate, following the state's first mystery coronavirus case in more than two months.

* Health authorities are scrambling to find the source, with a man in his 30s catching the virus after attending the sales at Chadstone Shopping Centre on December 26 and the Boxing Day Test at the MCG the following day.

* A further two overseas acquired infections were reported on Wednesday, bringing the state's active case total to 41.

* Victoria authorities are increasingly concerned about positive COVID-19 cases among international flight crews quarantining in Melbourne, with eight out of 1000 who arrived in the last fortnight testing positive - above the average for travellers arriving from overseas.

* Queenslanders who visited three regional NSW towns on the weekend have been asked to get tested for the coronavirus.

* Anyone from the sunshine state who was in Orange, Nyngan and Broken Hill between January 2 and 3 should get tested on Thursday "or earlier if possible", chief health officer Jeannette Young said.

* In WA, a nurse, a paramedic and a third person have gone into hotel isolation in Perth after safety protocols were breached when they came into contact with a COVID-19 patient who recently returned from the United Kingdom.

* The patient, a woman in her 80s, arrived from the United Kingdom on January 2 and was symptomatic on arrival and subsequently tested positive.

* Australia will be among the first countries to conditionally approve the Pfizer vaccine for COVID-19, following a decision to bring forward the rollout to early March.

* It is one of four vaccines the Australian government has purchased for a total projected supply of 134.8 million units.

* States are divided on mandatory hotel quarantine for international flight crews. Victoria introduced it last month, while Western Australia has required it since mid-2020.

AUSTRALIAN CORONAVIRUS NUMBERS

* There were 13 new virus cases recorded in Australia, including five in NSW (four local, one overseas acquired), three in Victoria (one local, two overseas acquired), two in Queensland (overseas acquired), and one in Western Australia (overseas acquired).

* The national death toll is 909: Victoria 820, NSW 56, Tasmania 13, WA 3, Queensland 1, SA 1 all in hotel quarantine.

GLOBAL CORONAVIRUS NUMBERS

* Cases: at least 86,385,273

* Deaths: at least 1,868,421

* Recovered: at least 48,439,113

* Source John Hopkins University and Medicine

HELPLINES/CONTACT INFORMATION

Australian Associated Press