TOKYO - A hospital in Okinawa has become a mega Covid-19 cluster with 196 patients in a month, of whom 64 died.

A high school in Miyazaki is reeling with heartbreak after being forced to withdraw from a national summer baseball tournament when 13 members of the team tested positive for Covid-19.

The 200,000 residents of Tokyo's Taito ward will not get their household waste cleared at least until the end of this month after 17 trash collectors became infected.

The highly contagious Delta variant has reared its ugly head in Japan in different ways in recent weeks. Among its victims are stationmasters at Shibuya, one of the world's busiest train stations; employees at Shinjuku's Lumine mall and Osaka's Hankyu mall; and members of pop idol group AKB48.

Prime Minister Yoshihide Suga, showing a rare glimpse of vulnerability, admitted at a news conference on Tuesday (Aug 17) that the ferocity of the spread of Covid-19, driven by the Delta variant, has been "completely unexpected".

This was his third Covid-19 news conference in six weeks, each time to expand and extend areas under a state of emergency or the lighter "quasi-emergency" even as the public has questioned his leadership and the apparent optimism behind the short periods of extension.

On Tuesday, Mr Suga prolonged ongoing emergency measures from the intended expiry of Aug 31 to Sep 12, while expanding the regions under an emergency from six prefectures to 13. Another 16 prefectures will come under lighter "quasi-emergency" measures.

"This has been a very long battle. I know that people are anxious, that even if they are following the rules things are not going well and they are feeling helpless, seeing their summer vacations being destroyed," he said.

"But with your cooperation, we can overcome these difficulties with strong resolve."

Mr Suga reiterated the three pillars that have long formed the basis of his Covid-19 strategy - fortifying the medical structure, preventing infections from spreading, and promoting vaccinations.

Vaccinations are proceeding steadily with about half the population having had at least their first dose, Mr Suga said. This puts Japan on track to reach his target of 80 per cent fully inoculated by October.

And while existing measures have proven to be woefully inadequate to curb the virus spread, Mr Suga on Tuesday tacked on initiatives including salary raises for doctors, the roll-out of "oxygen stations" to ensure those at home can get medical help, and requests for department stores to implement capacity limits.

He also urged the public to reduce by half any trips out of their homes, including to the supermarket.

But it remains to be seen if this will fall on deaf ears among a public that is sick and tired of Covid-19 curbs and as many companies mandate that their employees go to workplaces.

Tokyo has been under an emergency since July 12, during which the number of cases has leapt 5.5 times.

Under a new hospitalisation policy, only the sickest will be admitted, leaving more than 20,000 patients to recuperate at home. At least two people in their 30s have died at home in the capital.

There were 4,377 cases in Tokyo on Tuesday, with the number of seriously ill patients on life support climbing to a new record high of 276 people.

While Tokyo is the epicentre of Japan's fifth wave, it is but the tip of the iceberg, with the country recording 19,955 cases on Tuesday as the number of patients in intensive care or on life support rose to another new peak of 1,646. Daily case records tumbled in 18 prefectures.

All this is bad news for Mr Suga with a general election looming that will make or break his political fortunes. Cabinet approval ratings are plunging to new depths.

"I don't have many options left now," he said in a statement paving the way to the dissolution of the Lower House by Oct 21, when lawmakers' terms will expire. "Among the options I still have, I must choose but either way the prevention of Covid-19 is my top priority."

From Friday, Covid-19 restrictions will be in place in 29 of Japan's 47 prefectures. The measures, in place till Sept 12, will cover 106 million people, or 84.5 per cent of the population.

State of emergency (13 prefectures; 70.7 million people)

Ongoing: Tokyo, Saitama, Chiba, Kanagawa, Osaka, Okinawa
Enacted from Friday: Ibaraki, Tochigi, Gunma, Shizuoka, Kyoto, Hyogo, Fukuoka

Japan's state of emergency is akin to a very soft lockdown, without curtailment on the movement of people or the size of gatherings beyond loose requests to avoid "non-essential outings".

Legal penalties are aimed at the food and beverage sector, with eateries told to observe an 8pm curfew on dining in, and an all-day ban on alcohol sales. Those that flout guidelines may be fined up to 300,000 yen (S$3,730).

As clusters have emerged in crowded department stores, Mr Suga said on Tuesday that the local authorities will work with shopping malls to limit customer entry, though no penalties were announced.

Quasi-emergency (16 prefectures; 35.3 million people)

Ongoing: Hokkaido, Fukushima, Ishikawa, Aichi, Shiga, Kumamoto
Enacted from Friday: Miyagi, Yamanashi, Toyama, Gifu, Mie, Okayama, Hiroshima, Kagawa, Ehime, Kagoshima

Unlike a state of emergency that covers the entire prefecture, local authorities can implement focused "quasi-emergency" measures in specific municipalities.

Eateries are likewise asked to close at 8pm, though the serving of alcohol may be allowed until 7pm at the discretion of governors. Eateries that violate guidelines are liable to fines of up to 200,000 yen.