Australia's New South Wales (NSW) state reported its biggest daily rise in locally acquired cases of COVID-19 this year as officials struggle to stamp out a growing cluster of the highly infectious Delta variant.<br />'' <br />''The spike in cases after two weeks of a hard lockdown in Sydney, Australia's largest city raised the prospect of a further extension in restrictions, with officials blaming illegal family visits for a continuing rise in infections.<br />'' <br />''NSW reported 38 new local cases today, up from 27 a day earlier, with 11 of those having spent time in the community while infectious.<br />'' <br />''Given Australia's slow vaccine rollout, NSW state Premier Gladys Berejiklian implored residents to not visit homes of family and friends, citing the highly transmissible nature of the Delta strain.<br />'' <br />''A strict stay-at-home order has been in force in Sydney, home to a fifth of the country's 25 million population, since June 26.<br />'' <br />''The state's police force will deploy 100 additional officers in Sydney's south west, from tomorrow to ensure that residents are wearing masks and not breaking COVID-19 restrictions.<br />'' <br />''Prime Minister Scott Morrison said the federal government would ensure adequate economic support if the lockdown was extended, saying the state was on shifting sands and urged patience.<br />'' <br />''<span style="color: #222222;">Australia has fared much better than many other developed countries in keeping COVID-19 numbers low, with just under 30,900 cases and 910 deaths, however, the country's slow vaccination rollout has taken some of the shine off this success. Just over 9 per cent of people in NSW have been fully vaccinated, while about 29 per cent have had a first dose.</span><br />