Amid COVID Delta outbreak, Australia faces 'scariest period'

"Since the pandemic has started, this is perhaps the scariest period that New South Wales is going through," state Premier Gladys Berejiklian told reporters.

As officials fight to contain an outbreak of the highly contagious Delta variant, NSW has imposed tough restrictions in Sydney, Australia's largest city and home to a fifth of the country's 25 million population.

Health officials say that the transmission could be happening even through minimal contact with infected persons.

Eleven new local cases were reported on Thursday, taking the total infections in the latest outbreak to more than 40.

Thursday's data includes six cases detected after the cut-off deadline, which will be included in Friday's count.

Australia has reported just under 30,400 cases and 910 deaths since the pandemic began.

Preliminary evidence from England and Scotland suggests that people infected with Delta are about twice as likely to end up in the hospital, compared with those infected with Alpha.

The Delta variant has been linked to a resurgence of COVID-19 in Nepal, southeast Asia and elsewhere, but its UK spread has given scientists a clear picture of the threat it poses. Delta seems to be around 60% more transmissible than the already highly infectious Alpha variant (also called B.1.1.7) identified in the United Kingdom in late 2020.

Delta is moderately resistant to vaccines, particularly in people who have received just a single dose. A Public Health England study published on 22 May found that a single dose of either AstraZeneca's or Pfizer's vaccine reduced a person’s risk of developing COVID-19 symptoms caused by the Delta variant by 33%, compared to 50% for the Alpha variant. A second dose of the AstraZeneca vaccine boosted protection against Delta to 60% (compared to 66% against Alpha), while two doses of Pfizer’s jab were 88% effective (compared to 93% against Alpha).