[22] Unlike the case for Zika virus during the 2016 Summer Olympics in Rio de Janeiro, SARS-CoV-2 can be transmitted directly between humans, posing tougher challenges for the organizers to counteract the infectious disease and host a safe and secure event.

Other qualifying events that were due to take place in March to June 2020 began to be postponed until later in the year and mid-2021 as part of a wider suspension of international sporting competitions in response to the pandemic.

[37] It was subsequently revealed that twenty-three Chinese swimmers had tested positive for the drug trimetazidine, but were permitted to compete, after CHINADA claimed they had ingested tiny amounts unawares from a kitchen.

[50] Thomas Bach acknowledged in an interview on 20 May 2020, that the job of reorganizing the Tokyo Games was "a mammoth task" and also admitted that the event would have to be cancelled altogether if it could not take place in the summer of 2021.

[49][51] A member of the Japanese COVID-19 Advisory Committee on the basic action policy co-authored a British Medical Journal editorial, which stated, "holding Tokyo 2020 for domestic political and economic purposes—ignoring scientific and moral imperatives—is contradictory to Japan's commitment to global health and human security".

[55] It was reported in April 2021, just three months before the start of the Games, that there was still the option to cancel the Tokyo Olympics with the country having vaccinated less than 1% of its population, with tens of thousands of volunteers expected to take part and athletes not being required to quarantine after arriving in Japan.

[69] On 26 May 2021, the Asahi Shimbun newspaper, which was a local sponsor of the Games, published an editorial calling for Prime Minister Suga to "calmly and objectively assess the situation and decide on the cancellation of the event this summer.

[needs update] The disruption caused by postponing the Games was covered by the insurance policy, with those likely to make claims for their financial losses including local organizers, sponsors, hospitality firms, and travel providers.

[86] The Tokyo Organizing Committee was originally headed by former Japanese prime minister Yoshirō Mori,[87] but he resigned in February 2021 due to backlash from sexist comments about women in meetings.

[95] On 25 September, the IOC and Tokyo Organizing Committee agreed to a suite of measures to simplify the Games' logistics, including a cut to non-athlete staff, use of online meetings, and streamlined transport, among others.

There was criticism of the Zaha Hadid design—which was compared to a bicycle helmet and regarded as clashing with the surrounding Meiji Shrine—and widespread disapproval of the costs, even with attempts to revise and "optimize" the design.

[98] In June 2015, the government announced plans to reduce the new stadium's permanent capacity to 65,000 in its athletics configuration (although with the option to add up to 15,000 temporary seats for football) as a further cost-saving measure.

[109] In January 2020, counterterrorism drills began in different parts where the Games would take place, after intelligence data showed that terrorist groups could have carried out an attack seeking worldwide attention.

The torch was then expected to begin the second phase of its journey on 20 March, as it traveled for one week around the three most affected areas of the 2011 Tōhoku earthquake and tsunami—Miyagi, Iwate and Fukushima—where it would go on display under the heading "Flame of Recovery".

[129] On 23 July 2020 (one year ahead of the rescheduled opening ceremony), a promotional video was released featuring Japanese swimmer Rikako Ikee carrying the lantern inside Japan National Stadium, drawing comparisons between emergence from the pandemic and her own return to sport after being diagnosed with leukemia.

With around 300,000 local staff and volunteers entering and exiting these bubbles, and 20,000 vaccine doses allocated for this group, this led to concerns of COVID-19 spreading both during the Games and when teams returned to their countries.

[155] The opening ceremony was expected to be limited to fewer than 1,000 VIP guests, including IOC representatives and dignitaries,[156] while some events did allow members of other competing delegations to occupy spectator seats as well.

[138] Hashimoto cited uncertainties surrounding international travel restrictions, and goals to preserve the safety of all participants and spectators, and not place a burden on the health care system.

[150][151][154] A cultural program known as Nippon Festival was scheduled to coincide with the Olympics and Paralympics, running from April to September 2021 as a series of streaming events held by the Tokyo Organizing Committee and other partners.

[165] One of these events was a concert held on 18 July, which featured J-rock band Wanima, choreography by dancers Aio Yamada and Tuki Takamura, and the presentation of animated "creatures" based on illustrations "embodying the thoughts and emotions of people from across the world".

[166] The original plans for Nippon Festival included events such as Kabuki x Opera (a concert that would have featured stage actor Ichikawa Ebizō XI, opera singers Anna Pirozzi and Erwin Schrott, and the Tokyo Philharmonic Orchestra), an arts and culture festival focusing on disabilities,[167][168][169][170] and a special two-day exhibition sumo tournament at the Ryōgoku Kokugikan shortly after the Olympics—which would have differed significantly from the traditional bi-monthly Honbasho tournaments, and featured special commentary in English and Japanese to help explain to spectators the customs and traditions of professional sumo, which are deeply rooted in the Shinto religion.

On 21 July 2021, Guinea announced it would not be sending a delegation to the Tokyo Olympics, allegedly due to COVID-19 concerns, though media outlets suggested that financial considerations may have been the real motivating factor.

Satō chose not to employ any musical elements distinctive to Japan "because victory ceremonies are for athletes from around the world" and he wanted all medalists to "feel at ease" when taking their places on the podium, regardless of their nationality.

[240][241] In March 2020, a Japanese businessman admitted to giving gifts, including cameras and watches, to IOC officials in order to lobby for their support of Tokyo's bid to host the Olympic Games.

Petitions, containing more than 140,000 signatures in total, were delivered to the Japanese embassies in Switzerland and Germany, expressing concerns over claims of using tropical wood sourced from Shin Yang, a Malaysian company with a record of human rights abuses, illegal logging, and rainforest destruction.

[254][255] Use of the flag in international sporting events such as the Olympic Games is controversial because it was used for waging aggressive war against many countries in Pacific regions, including the attack on Pearl Harbor.

"[282] A number of controversies arose during the Games, most notably the attempted repatriation on 1 August of Belarusian sprinter Krystsina Tsimanouskaya, allegedly for her criticism of the national sports authorities and team management.

[283] Refusing to return to Belarus, over fears for her safety,[284] Tsimanouskaya sought assistance from the IOC and traveled to Warsaw, Poland, on 4 August after being granted a humanitarian visa by Tokyo's Polish Embassy.

[291] In May 2022, former international diver, Olympic judge and previous member of FINA's Technical Diving Committee from New Zealand Simon Latimer revealed he had sent a whistleblower complaint[292] to FINA's Executive Director Brent Nowicki in December 2021 detailing Zhou's alleged "unethical behavior" which also contained allegations that Zhou coached Chinese divers during major events during the 2020 Summer Olympics and she had manipulated judging panels in order to benefit Chinese athletes.

Subsequent to Latimer's complaint, video evidence emerged online showing Zhou coaching Chinese divers during competition sessions at the Olympics,[293] a behavior considered unethical given her supposedly neutral role as a FINA Vice President and Diving Bureau Liaison.