Here's a look at the strict entry protocols for the current handful of travellers coming into Japan, and what could happen with athletes during the Olympic Games.
Tokyo Olympics 2020: Games will happen 'however coronavirus evolves', says organising committee chief
Japan's Prime Minister Yoshihide Suga is expected to announce a month-long extension of a virus state of emergency later Tuesday - meaning the measure will run until 7 March in Tokyo and several other parts of the country.
In a letter to Team USA athletes posted on the US Olympic website, US Olympic and Paralympic Committee chief Sarah Hirshland warned competitors to be adaptable and open to making sacrifices
The artistic swimming event will double as the sport's final qualifier for the virus-postponed Games. It was due to be held on 4-7 March in Tokyo but will now take place two months later.
Gates, whose foundation has donated $1.75 billion towards efforts to fight Covid-19, told Kyodo that the next few months would be crucial for the postponed 2020 Games.
Organisers and the International Olympic Committee are finally going public with their planning, hoping to push back against reports the Olympics will be cancelled
Organisers of the virus-postponed 2020 Games, denying cancellation is on the cards, have floated the possibility of holding competitions behind closed doors.
Jimmy Patronis sent a letter to Thomas Bach, the head of the IOC, "to encourage you to consider relocating the 2021 Olympics from Tokyo, Japan to the United States of America, and more specifically to Florida."
While vaccination programmes are kicking into gear around the globe, they are still focusing on those facing the highest risk, so the question of whether elite athletes should be a priority is, for now, awkward.
Tokyo Olympics get underway in exactly six months from today, on 23 July, but the future remains unclear owing to the pandemic situation.
Tokyo Olympics 2020: Don't shout, don't cheer the likely experience ahead for fans - if they're allowed in
This month's Emperor's Cup football final at Tokyo's National Stadium, the main Olympic venue, provided a glimpse of what could be in store for the Games.
Tokyo Olympics 2020: Japan says 'no truth' in Games cancellation report; PM Yoshihide Suga 'determined' to host
Tokyo 2020 organisers, when asked about the report, said they were focused on delivering a "safe and secure" Games.
His words come as recent polls in Japan show 80% of the public believe the Olympics should not happen with virus cases surging — or will not happen.
The comments by Canadian IOC member Richard Pound to BBC came as Japanese Prime Minister Yoshihide Suga declared a state of emergency on Thursday for Tokyo and surrounding prefectures.
The rapid spread of the virus in Japan is imperiling plans for the postponed Tokyo Olympics, which are to open on 23 July . The Paralympics begin on 24 August.
It's nearing deadline time for Tokyo Olympic organisers, the International Olympic Committee, and various Japanese government entities as they try to pull off the Games in the middle of a pandemic.
Tokyo Olympic organisers announced earlier this week that their new budget, swollen by the postponement and the cost of holding the Olympics during a pandemic, had increased by $2.8 billion, pushing the official cost to $15.4 billion.
A poll released by national broadcaster found just 27 percent of respondents support holding the Games next year, with 32 percent backing cancellation and 31 percent favouring a further postponement.
Fans and foreign athletes will be allowed at some of the test events, which will also be used to assess anti-coronavirus measures and contingency plans.
Japan has experienced an uptick of the infections this month with a nationwide daily total exceeding 2,000 as the government tries to balance preventive measures and business activity without further hurting the pandemic-hit economy.