COVID-19: What you need to know about the coronavirus pandemic this week

Confirmed cases of COVID-19 have passed 608.6 million globally, according to Johns Hopkins University. The number of confirmed deaths has now passed 6.51 million. More than 12.63 billion vaccination doses have been administered globally, according to Our World in Data.

New York state has ended its COVID-19 requirement that masks be worn on trains, buses and other modes of public transport – as well as in airports and ride-share vehicles.

Pfizer has donated 100,000 courses of its COVID-19 antiviral treatment Paxlovid to a new group aiming to improve access to the drug in low and middle-income countries.

The United States is set to boost its stockpile of at-home COVID-19 tests, having ordered more than 100 million from domestic manufacturers.

The Chinese city of Shanghai has extended free regular COVID-19 testing to 31 October.

North Korean leader Kim Jong Un has suggested that the country could begin COVID-19 vaccinations in November, state media reported.

Scientists from leading academic centres are joining forces to examine long COVID and look at whether fragments of COVID-19 persisting in the tissues of some individuals could be the root cause of the condition.

The effort, known as the Long Covid Research Initiative, aims to streamline research and quickly pivot to clinical trials of potential treatments. By sharing diverse skill sets and resources, the group hopes to uncover the scientific underpinnings of the disease and use that to design evidence-based trials.

The team includes scientists from Harvard University, Stanford University, the University of California, San Francisco, Yale University and the J. Craig Venter Institute.

The Chinese city of Chengdu extended a lockdown for a majority of its more than 21 million residents on Thursday to prevent further transmission of COVID-19. Millions more people in other parts of China have been told to avoid travel during upcoming holidays.

Chengdu, the capital of Sichuan province in southwestern China, was locked down on 1 September after the detection of COVID cases. This made it the largest Chinese metropolis to face COVID restrictions since Shanghai's lockdown in April and May.

The lockdown had been expected to be lifted last Wednesday, but officials said late in the day that the virus still poses a risk in some areas.

Elsewhere, cities have urged residents to refrain from non-essential trips in the run-up to the week-long National Day holiday at the beginning of October and a Communist Party Congress in mid-October.