Coronavirus deaths in the United States surged to their highest level in months on Wednesday as Muslim pilgrims began a pandemic-curtailed version of their sacred hajj.
The human toll of the disease in the US hit a magnitude not seen since mid-May with nearly 1,600 deaths recorded in 24 hours for the world's hardest-hit country, Johns Hopkins University reported Tuesday.
Meanwhile China, where the deadly pathogen was first detected late last year, reported its highest single-day case total in three months. Residents in the semi-autonomous city of Hong Kong were adjusting to their strictest social-distancing measures yet over fears a "large-scale" outbreak could overwhelm hospitals.
COVID-19 has claimed 660,000 lives and infected more than 16.7 million people across the globe, according to an AFP tally of official figures, although experts believe the true infection rate could be wildly higher.
A second startling study from India in under a week, based on blood tests from almost 7,000 people, revealed more than half those living in the slums of Mumbai have had the coronavirus.
- Clusters and lockdowns -
Case numbers have been rising across the US for weeks, leaving health authorities and leaders to watch nervously for a feared spike in fatalities.
President Donald Trump's push for re-election in November has been dogged by the virus crisis that has already killed nearly 150,000 Americans and wrought havoc on the world's biggest economy.
In a fresh blow to the president, Twitter removed a video that Trump retweeted in which doctors made allegedly false claims about the pandemic, saying it broke its "COVID-19 misinformation policy".
China, which Trump has often criticised for its initial handling of the pandemic, reported a three-month high of 101 new virus cases Wednesday as sporadic regional outbreaks illustrated the mammoth task of keeping contagion at bay.
Authorities have concentrated their attention on a cluster that emerged last week in the northeastern port city of Dalian, where officials said workers handled contaminated packaging of imported seafood.
More than three million people have been tested there and enclosed public venues including libraries, gyms and restaurants will be closed.
Hong Kong's leader Carrie Lam warned the financial hub was "on the verge of a large-scale community outbreak, which may lead to a collapse of our hospital system and cost lives, especially of the elderly".
From Wednesday all residents in the densely packed city of 7.5 million must wear masks when they leave their homes, while restaurants can only serve takeaway meals, in a blow for diners during the city's hot and humid summer.
"It's so hot outside now," a construction worker, who gave his surname as Chow, told AFP as he tucked into a pork chop in an alcove outside a department store.
"Ten minutes after I start work, my shirt is all sweaty," he said, adding that he missed the air-conditioning of restaurants.
And there were distressing scenes in Australia, where a care home resident who had died of the virus was seen being wheeled away in a body bag, while other residents waited for transport to hospital.
Prime Minister Scott Morrison warned of a "critical" situation at more than a dozen care homes in Melbourne, where disaster-relief teams have been deployed to overwhelmed nursing facilities.
- Hampered hajj -
Resurgent outbreaks have forced nations to step up measures against the virus, leaving tourism and event calendars in tatters.
The annual hajj pilgrimage to Saudi Arabia's Mecca drew 2.5 million Muslims last year, but in 2020 just 10,000 already living in the kingdom will be allowed in.
The chosen ones were subject to electronic tagging, temperature checks and quarantine as they began trickling into Mecca over the weekend.
In addition to being a spiritual rite for faithful Muslims, the pilgrimage normally provides a boost to the local economy that will be sorely missed this year.
In Europe, swelling caseloads are blasting a similar hole in local hopes for a financial windfall in summer holiday hotspots.
Spain, one of the countries hit hardest by the pandemic, insists it is a safe destination despite dealing with 361 active outbreaks and more than 4,000 new cases.
Several countries have nonetheless imposed quarantines on people returning from Spain, including its biggest tourist market, Britain.
Spain's strict lockdown destroyed more than a million jobs during the second quarter of the year, the National Statistics Institute reported -- mainly in tourism.