The Tokyo 2020 and Beijing 2022 Olympic Games held during the COVID-19 pandemic: planning, outcomes, and lessons learnt.

The COVID-19 pandemic profoundly affected all mass gatherings for sporting and religious events, causing cancellation, postponement, or downsizing. On March 24, 2020, the Japanese Government, the Tokyo Organising Committee of the Olympic and Paralympic Games, and the International Olympic Committee decided to postpone the Tokyo 2020 Olympic and Paralympic Games until the summer of 2021. With the emergence of SARS-CoV-2, the potential creation of a superspreading event that would overwhelm the Tokyo health system was perceived as a risk. Even with a delayed start date, an extensive scale of resources, planning, risk assessment, communication, and SARS-CoV-2 testing were required for the Games to be held during the COVID-19 pandemic. The effectiveness of various mitigation and control measures, including the availability of vaccines and the expansion of effective testing options, allowed event organisers and the Japanese Government to successfully host the rescheduled 2020 Tokyo Olympic Games from July 23 to Aug 8, 2021 with robust safety plans in place. In February and March, 2022, Beijing hosted the 2022 Winter Olympic Games as scheduled, built on the lessons learnt from the Tokyo Games, and developed specific COVID-19 countermeasure plans in the context of China's national framework for the plan called Zero COVID. Results from the testing programmes at both the Tokyo and Beijing Games show that the measures put in place were effective at preventing the spread of COVID-19 within the Games, and ensured that neither event became a COVID-19-spreading event. The extensive experience from the Tokyo and Beijing Olympic Games highlights that it is possible to organise mass gatherings during a pandemic, provided that appropriate risk assessment, risk mitigation, and risk communication arrangements are in place, leaving legacies for future mass gatherings, public health, epidemic preparedness, and wider pandemic response.

Fatal SARS-CoV-2 Infection among Children, Japan, January-September 20221.

To determine the characteristics of pediatric patients 0-19 years of age who died after onset of SARS-CoV-2 infection in Japan during January 1-September 30, 2022, we reviewed multiple sources. We identified 62 cases, collected detailed information from medical records and death certificates, and conducted interviews, resulting in 53 patients with detailed information for our study. Among 46 patients with internal causes of death (i.e., not external causes such as trauma), 15% were <1 year of age, 59% had no underlying disease, and 88% eligible for vaccination were unvaccinated. Nonrespiratory symptoms were more common than respiratory symptoms. Out-of-hospital cardiac arrest affected 46% of patients, and time from symptom onset to death was <7 days for 77%. Main suspected causes of death were central nervous system abnormalities (35%) and cardiac abnormalities (20%). We recommend careful follow-up of pediatric patients after SARS-CoV-2 infection during the first week after symptom onset, regardless of underlying diseases.

The importance of meropenem resistance, rather than imipenem resistance, in defining carbapenem-resistant Enterobacterales for public health surveillance: an analysis of national population-based surveillance.

BACKGROUND: In Japan, carbapenem-resistant Enterobacterales (CRE) infections were incorporated into the National Epidemiological Surveillance of Infectious Diseases (NESID) in 2014, necessitating mandatory reporting of all CRE infections cases. Subsequently, pathogen surveillance was initiated in 2017, which involved the collection and analysis of CRE isolates from reported cases to assess carbapenemase gene possession. In this surveillance, CRE is defined as (i) minimum inhibitory concentration (MIC) of meropenem ≥2 mg/L (MEPM criteria) or (ii) MIC of imipenem ≥2 mg/L and MIC of cefmetazole ≥64 mg/L (IPM criteria). This study examined whether the current definition of CRE surveillance captures cases with a clinical and public health burden. METHODS: CRE isolates from reported cases were collected from the public health laboratories of local governments, which are responsible for pathogen surveillance. Antimicrobial susceptibility tests were conducted on these isolates to assess compliance with the NESID CRE definition. The NESID data between April 2017 and March 2018 were obtained and analyzed using antimicrobial susceptibility test results. RESULTS: In total, 1681 CRE cases were identified during the study period, and pathogen surveillance data were available for 740 (44.0%) cases. Klebsiella aerogenes and Enterobacter cloacae complex were the dominant species, followed by Klebsiella pneumoniae and Escherichia coli. The rate of carbapenemase gene positivity was 26.5% (196/740), and 93.4% (183/196) of these isolates were of the IMP type. Meanwhile, 315 isolates were subjected to antimicrobial susceptibility testing. Among them, 169 (53.7%) fulfilled only the IPM criteria (IPM criteria-only group) which were susceptible to meropenem, while 146 (46.3%) fulfilled the MEPM criteria (MEPM criteria group). The IPM criteria-only group and MEPM criteria group significantly differed in terms of carbapenemase gene positivity (0% vs. 67.8%), multidrug resistance rates (1.2% vs. 65.8%), and mortality rates (1.8% vs 6.9%). CONCLUSION: The identification of CRE cases based solely on imipenem resistance has had a limited impact on clinical management. Emphasizing resistance to meropenem is crucial in defining CRE, which pose both clinical and public health burden. This emphasis will enable the efficient allocation of limited health and public health resources and preservation of newly developed antimicrobials.

Epidemiologic Trends and Distributions of Imported Infectious Diseases Among Travelers to Japan Before and During the COVID-19 Pandemic, 2016 to 2021: A Descriptive Study.

BACKGROUND: Little is known about the trends of imported infectious diseases among travelers to non-endemic countries during the novel coronavirus disease 2019 (COVID-19) pandemic. This article aimed to describe those among travelers to Japan. METHODS: This is a descriptive study based on national surveillance data. Imported infectious disease cases were defined as those with a reported overseas source of infection among 15 diseases pre-selected based on the probability and impact of importation. The number of notified cases from April 2016 to March 2021 were described by disease and time of diagnosis. The relative ratio and absolute difference in case counts-both by number and per arrival-were calculated by disease comparing those from the pandemic period (April 2020-March 2021) to the pre-pandemic period (April 2016-March 2020). RESULTS: A total of 3,524 imported infectious disease cases were diagnosed during the study period, including 3,439 cases before and 85 cases during the pandemic. The proportionate distribution of diseases changed but notification counts of all 15 diseases decreased during the pandemic. Accounting for arrivals, however, seven diseases showed a two-fold or greater increase, with a notable absolute increase per million arrivals for amebiasis (60.1; 95% confidence interval [CI], 41.5-78.7), malaria (21.7; 95% CI, 10.5-33.0), and typhoid fever (9.3; 95% CI, 1.9-16.8). CONCLUSION: The epidemiology of imported infectious diseases changed during the pandemic. While the number of imported infectious disease cases decreased, the number of cases per arrivals increased considerably both in relative and absolute terms for several diseases of public health and clinical importance.

National Surveillance of Pediatric Acute Hepatitis of Unknown Etiology, Japan, October 2021-December 2022.

Pediatric acute hepatitis of unknown etiology has been reported globally since April 2022. In Japan, 139 possible cases with onset dates after October 2021 were reported as of December 2022. Three patients required liver transplants, but none died. Rates of adenovirus positivity (11/125, 9%) were lower than those for other countries.

SARS-CoV-2 Infection in Wrestlers after International Tournaments, April 2021.

Epidemiologic and genomic investigation of SARS-CoV-2 infections in members of Japan's national wrestling team after participation in international tournaments in 2021 revealed multiple lineages of SARS-CoV-2 not reported in Japan. The attack rate among wrestlers was high. Results suggest possible transmission during matches. We recommend early case detection and response practices.

Invasive Haemophilus influenzae disease among adults in Japan during 2014-2018.

PURPOSE: We describe the epidemiology of invasive Haemophilus influenzae disease (IHD) among adults in Japan. METHODS: Data for 200 adult IHD patients in 2014-2018 were analyzed. The capsular type of H. influenzae was determined by bacterial agglutination and polymerase chain reaction (PCR), and non-typeable Haemophilus influenzae (NTHi) was identified by PCR. RESULTS: The annual incidence of IHD (cases per 100,000 population) was 0.12 for age 15-64 years and 0.88 for age ≥ 65 years in 2018. The median age was 77 years, and 73.5% were aged ≥ 65 years. About one-fourth of patients were associated with immunocompromising condition. The major presentations were pneumonia, followed by bacteremia, meningitis and other than pneumonia or meningitis (other diseases). The case fatality rate (CFR) was 21.2% for all cases, and was significantly higher in the ≥ 65-year group (26.1%) than in the 15-64-year group (7.5%) (p = 0.013). The percentage of cases with pneumonia was significantly higher in the ≥ 65-year group than in the 15-64-year group (p < 0.001). The percentage of cases with bacteremia was significantly higher in the 15-64-year group than in the ≥ 65-year group (p = 0.027). Of 200 isolates, 190 (95.0%) were NTHi strains, and the other strains were encapsulated strains. 71 (35.5%) were resistant to ampicillin, but all were susceptible to ceftriaxone. CONCLUSION: The clinical presentations of adult IHD patients varied widely; about three-fourths of patients were age ≥ 65 years and their CFR was high. Our findings support preventing strategies for IHD among older adults, including the development of NTHi vaccine.