Spanish children were allowed outside on Sunday for the first time in six weeks as countries eased lockdown measures and reopen economies gutted by the coronavirus pandemic that has infected nearly three million people worldwide.

Governments from France to Italy and the United States are gearing up for a partial easing of severe restrictions that have kept more than half of humanity indoors for weeks on end.

Coronavirus cases around the world rose to 2.9 million and deaths have doubled since April 10 — hitting nearly 203,000 people on Sunday — with well over half of them in Europe, according to an AFP tally.

The daily toll in Western countries appeared to be levelling off and even falling, but fears abound in many places of a second surge after restrictions on movement are lifted.

Governments are planning to slowly peel back lockdown measures in order to avoid a sudden rush back to normal life — and the risk of a resurgence amid warnings from the World Health Organisation (WHO) that recovered people might not be immune to re-infection.

Children let out in Spain

Spanish families embraced new rules allowing children outside for the first time since March 14, with kids hopping on bicycles and scooters on the streets of Madrid and Barcelona — some wearing small masks and gloves.

"They are super excited, very, very impatient. They were up at 6:30 am, saying 'We are going out, We are going out!'," Inmaculada Paredes told AFP, readying to take her seven and four-year-old kids outdoors.

Under the revised rules, children are allowed out once per day between 9:00 am and 9:00 pm, but cannot venture more than one kilometre from their homes.

The new rules were rolled out as the death toll in the hard-hit country dropped to 288 people on Sunday, the lowest since March 30.

With more than 23,000 fatalities, Spain has the third highest death toll in the world after Italy's 26,000 and more than 53,000 in the United States.

Other hard-hit countries across Europe are also starting to look toward a slow crawl back to normality.

Italy on Sunday said schools would reopen in September, while many businesses could resume work next week, and France was expected to unveil details of its de-confinement plan on Tuesday.

Belgium said schools and businesses will reopen from mid-May, while Germany started to reopen some shops earlier this week.

Ramadan at home

Meanwhile, Saudi Arabia on Sunday said it would partially lift its 24-hour curfew, allowing malls and retailers to open their doors during certain hours.

But the kingdom said it would maintain a round-the-clock lockdown in the Muslim holy city of Makkah.

Worshippers in the country joined hundreds of millions of Muslims around the world who marked the second day of Ramadan at home, avoiding traditional, large family meals to break their day-time fasts under social distancing rules.

Rejecting the advice of top disease experts, the US state of Georgia allowed thousands of businesses to resume operations, from hairdressers to bowling alleys.

"How long are we supposed to imprison ourselves?" questioned 30-year-old Mackenzie Scharf, one of many in Georgia embracing the return to something resembling normalcy.

"This is much safer than going grocery shopping," she told AFP on the beach at Tybee Island, where her five-year-old son flew a kite under a cloudless sky.

US President Donald Trump has repeatedly said he wants to resume business in the world's biggest economy, even as medical advisors have cautioned against easing lockdown too soon or too fast.

The US leader faced a fresh volley of criticism after suggesting that coronavirus could be treated by shining ultraviolet light inside patients' bodies, or with injections of household disinfectant.

He lashed out at the media on Twitter, accusing journalists of posing hostile questions, and suggested his daily coronavirus briefings were not worth his time.

Immunity warning

While new reported cases appear to have plateaued at about 80,000 a day, the world remains in wait as companies and governments race to develop treatments and, eventually, a vaccine for the virus.

Some governments are studying measures such as "immunity passports" as one way to get people back to work after weeks of shutdowns that have roiled the global economy.

"If I've already had corona then I'm not infectious," said Berlin resident Lothar Kopp, hoping to test positive for antibodies as it could allow him to visit his elderly mother.

But the WHO warned that people who survive infection cannot be certain they will not be hit again by the respiratory disease, which first emerged in China late last year.

"There is currently no evidence that people who have recovered from Covid-19 and have antibodies are protected from a second infection," the UN health body said in a statement.

The White House's top pandemic advisor Dr Anthony Fauci said this week that the US will certainly have a coronavirus problem in the fall, which could be complicated by the return of seasonal flu towards the end of the year.

Meanwhile in Beijing, a new set of regulations were introduced to combat the pandemic, banning "uncivilised" behaviour such as not covering the mouth and nose when coughing or sneezing.

Virus numbers in China have dwindled as it begins to cautiously lift control measures, although fears remain over a potential resurgence and imported infections from abroad.