TOKYO (BLOOMBERG) - Japan is emerging as one of the riskiest places for the spread of the coronavirus, prompting criticism that Prime Minister Shinzo Abe's government has misfired on its policies to block the outbreak.

The number of infections in Japan, outside the Diamond Priness, has more than doubled in the past week to 84 - same number of cases as Singapore on Thursday (Feb 20). The two countries have the most number of cases outside mainland China.

The government is being faulted for being too slow to bar visitors from China and too lax in its quarantine of the Diamond Princess cruise ship, where infections surged during two weeks docked in Yokohama.

While the hundreds of cases aboard the ship have grabbed the world's attention, they are not counted among Japan's total.

What appears to be more troublesome is that Japan is starting to see a surge in cases in multiple areas across the country - sometimes with little to link the outbreaks.

Adding to the worries is that passengers began leaving the quarantined vessel on Wednesday (Feb 19) amid concerns some might later test positive and take the virus to more parts of Japan.

The situation is growing more alarming, as Japan's elderly population and work ethic present high-risk scenarios for the outbreak's spread.

"The Japanese government's decision to wait for the China-friendly WHO to make its much-delayed declaration of a global health emergency led to the first cases of domestic person-to-person transmission and tarnished the country's international reputation," Mr Richard Koo, chief economist at Nomura Research Institute, wrote in a report.

"The coronavirus will probably cause a substantial amount of economic damage in Japan," Mr Koo wrote.

The Abe administration, he says, "managed to completely drop the ball on this issue".

A Bloomberg survey released on Wednesday showed that economists see Japan falling into recession as the coronavirus pummels an economy already weakened by a sales tax hike.

While a handful of the cases in the country are evacuees from Hubei province, the vast majority are Japan residents, many with no history of travelling to China.

Among those have been several taxi drivers, suspected of having extensive interactions with the public before their diagnoses.

A party on board a pleasure boat for a group of taxi drivers is believed to be at the heart of one cluster of cases in Tokyo, spreading to at least 11 people.

Among those infected was the mother-in-law of one of the drivers, who became Japan's only confirmed domestic death from the virus to date.

Health experts warn that the countries with the greatest public risks for the virus are poor states with few resources to fight the disease, such as China's neighbour North Korea.

Developed states with advanced healthcare systems like Japan are best suited to treat patients and conduct tests to find those infected.

'COMPLETELY INADEQUATE'

As the threat of the coronavirus became apparent in January, Japan's stance of rejecting travel bans for Chinese tourists stood in stark contrast to nations such as Australia, which barred entry. Chinese tourism to Japan hit a January record high, with Tokyo's travel curbs only taking effect on Feb 1.

And while businesses in Hong Kong and Singapore implemented work-from-home experiments on a scale never before seen, Mr Abe merely acknowledged telework as "one effective strategy".

While a growing number of companies are banning events and allowing employees to work from home to contain the spread, there has been little push to implement a wide-scale lockdown.

Tokyo rush-hour trains remained as packed as ever, leading Mr Abe to call on Japan's famously hard-working residents to stay home from work or students from school if they suspect they have a cold.

With the cases mounting internally, Japan received a rare rebuke from the US Centres for Disease Control and Prevention over the way it managed the quarantine on the cruise ship, saying "it may not have been sufficient to prevent transmission".

The US and others placed a 14-day quarantine on repatriated nationals, but about 500 people cleared by Japan left the ship on Wednesday to go about their normal lives, and were told to call the authorities if they feel ill.

In a video posted to YouTube that went viral in Japan, Professor Kentaro Iwata, a specialist of infectious diseases at Kobe University Hospital who said he boarded the Diamond Princess, slammed the attempt to quarantine the boat.

"The cruise ship was completely inadequate in terms of infection control," Dr Iwata said, adding there was no distinction between zones for those infected and those uninfected.

He said he was later removed from the ship after criticising the response and called on international bodies to ask Japan to change its actions.

The government has defended its policies and may have been stretched to find a facility on land to place the 3,700 people aboard the cruise ship in quarantine.

INFECTION PATH

An admission by the nation's Health Minister Katsunobu Kato on Sunday that Japan had lost track of the route of some of the cases of infection shocked many, and has led to increasing criticism of the government's control efforts.

"It's not correct to say they lost the path of infection," Mr Kazuhiro Haraguchi, a politician with the opposition Democratic Party for the People and former minister, said on Twitter.

"By taking steps like only checking people from Hubei, they didn't try to understand the full infection, or the dangers."

A mass outbreak native to Japan is something the nation can ill afford, with two of its top economic standouts - a booming tourism sector and the 2020 Olympics - potentially under threat from the outbreak in China.

In the absence of travel bans, visitors to Japan fell only 1.1 per cent in January, a drop that was mainly due to an ongoing spat with South Korea, with tourists from China lodging a surprising 23 per cent increase compared with the year earlier.

Meanwhile, the World Health Organisation and the International Olympic Committee have refused to countenance any cancellation of the Olympics, set to begin in July.

Others have said there is little that can be done to prevent the eventual spread of the disease.

"This virus spread very, very fast. Not only China, not only Japan, but also many other countries cannot catch up with the speed of this virus," professor of virology Hitoshi Oshitani of Tohoku University told reporters in Tokyo.

Prof Oshitani also sits on the government panel tackling the virus.

"Even if they implemented a travel ban to all of China, it is too late."