SYDNEY: Health officials in New South Wales (NSW), Australia, announced on Friday that the Omicron sub-lineage BA.4 had been detected in the state. According to reports, the first case of BA.4 in NSW was a traveller who returned from South Africa.

Meanwhile, Covid-19 infections are on the rise in NSW, with 11,903 new cases and seven deaths reported on Friday. In hospitals, there are 1,645 cases, with 68 in intensive care units.

James Wood, a mathematician at the University of New South Wales' School of Public Health and Community Medicine, told the Sydney Morning Herald that thousands of Australians are likely to have been reinfected with the virus after various strains surfaced.  "Within the next several months, we'll see new sub-variants triggering higher transmission in Australia." Masks will no longer be required in Western Australia (WA) as of Friday, except in high-risk environments such as hospitals, residential aged care, airports, and public transportation.

All venues in the state will be free of the two-square-meter regulation and capacity limits, and asymptomatic close contacts will no longer be required to isolate for seven days.  Immunization restrictions for interstate travellers are also eliminated, however the requirement for overseas entrants to receive two doses of vaccination remains.

"According to the latest health advise, WA achieved its peak four weeks ago, with case numbers stable and lower than predicted, and hospitalisation and ICU admission rates constant and lower than anticipated," the WA government said in a statement.

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