Incidence and length of outbreak period of COVID-19 and population density in comparison with seasonal influenza in Japan.

Objectives: There is no consensus regarding the impact of population density on the transmission of respiratory viral infections such as COVID-19 and seasonal influenza. Our study aimed to determine the correlation between population density and the incidence and duration of COVID-19 transmission. Methods: Publicly available data for confirmed COVID-19 cases in Japan, from January 2020 through November 2021, were retrospectively collected. The average numbers of seasonal influenza cases reported in the national database from 2013-2014 through 2019-2020 were identified. Using data for COVID-19 and seasonal influenza population density and incidence rates (age-adjusted), the Pearson's correlation coefficient was determined. Results: A significant positive correlation between log population density and length of outbreak period was observed for COVID-19 (r = 0.734; p < 0.001) but not for seasonal influenza. Additionally, a significant linear correlation was observed between population density and age-adjusted incidence rate for COVID-19 (r = 0.692; p < 0.001) but not for seasonal influenza. Conclusions: In Japan, areas with high population density experienced a prolonged and more intense COVID-19 outbreak compared with areas with low population density. This was not observed with seasonal influenza, suggesting that public health measures against COVID-19 should be tailored according to population density.

Epidemiological Factors Associated with COVID-19 Clusters in Medical and Social Welfare Facilities.

The characteristics of coronavirus disease 2019 (COVID-19) clusters in medical and social welfare facilities and the factors associated with cluster size are still not yet fully understood. We reviewed COVID-19 cases in Japan identified from January 15 to April 30, 2020 and analyzed the factors associated with cluster size in medical and social welfare facilities. In this study, COVID-19 clusters were identified in 56 medical and 34 social welfare facilities. The number of cases in those facilities peaked after the peak of the general population. The duration of occurrence of new cases in clusters was positively correlated with the number of cases in both types of facilities (rho = 0.44, P < 0.001; and rho = 0.69, P < 0.001, respectively). However, the number of days between the first case in a prefecture and the onset of clusters was negatively correlated with the number of cases only in clusters in social welfare facilities (rho = - 0.4, P = 0.004). Our results suggest that COVID-19 cases in those facilities were prevalent in the latter phase of the disease's community transmission, although the underlying mechanisms for such a trend could differ between medical and social welfare facilities.

Integration of publicly available case-based data for real-time coronavirus disease 2019 risk assessment, Japan.

In response to the outbreak of coronavirus disease 2019 (COVID-19) in Japan, a national COVID-19 cluster taskforce (comprising governmental and nongovernmental experts) was established to support the country's Ministry of Health, Labour and Welfare in conducting daily risk assessment. The assessment was carried out using established infectious disease surveillance systems; however, in the initial stages of the pandemic these were not sufficient for real-time risk assessment owing to limited accessibility, delay in data entry and inadequate case information. Also, local governments were publishing anonymized data on confirmed COVID-19 cases on their official web sites as daily press releases. We developed a unique database for nationwide real-time risk assessment that included these case lists from local government web sites and integrated all case data into a standardized format. The database was updated daily and checked systematically to ensure comprehensiveness and quality. Between 15 January 2020 and 15 June 2021, 776 459 cases were logged in the database, allowing for analysis of real-time risk from the pandemic. This semi-automated database was used in daily risk assessments, and to evaluate and update control measures to prevent community transmission of COVID-19 in Japan. The data were reported almost every week to the Japanese Government Advisory Panel on COVID-19 for public health responses.

Perceptions and behaviours related to COVID-19 in patients with rheumatoid arthritis: a cross-sectional study.

OBJECTIVES: To study the perceptions and behavioural changes related to the coronavirus disease 2019 (COVID-19) in patients with rheumatoid arthritis (RA) and determine their associations with patient characteristics, such as health literacy. METHODS: This cross-sectional study was conducted from September to November of 2020 and included 400 outpatients with RA aged 18 and above. We measured self-reported perceptions as outcomes, such as awareness, knowledge and behaviours related to COVID-19. Health literacy and other characteristics as exposures were investigated using self-report questionnaires and electronic health records. To analyse the association between patient factors and the outcomes, multivariable linear and logistic regression models were performed. RESULTS: In total, 365 patients completed the survey. More than half (51%) of patients reported that they were 'very worried' about possible infection with COVID-19, whereas over 80% believed the possibility of getting COVID-19 was low. In the multivariable analyses, patients with low health literacy had limited knowledge about COVID-19 and did not change daily routines and perform preventive measures. CONCLUSIONS: In this pandemic, healthcare providers may need to be aware of more vulnerable individuals and share COVID-19 related information promptly and effectively with their patients. Key Points • This cross-sectional study aimed to investigate the perceptions and behavioural changes related to COVID-19 in patients with RA. • All patients were aware of COVID-19 and most of them worried about getting infected. • Health literacy, age, sex, disease activity and rheumatic drugs were associated with perceptions and behaviours related to COVID-19.

The Flight Evacuation Mission for COVID-19 from Wuhan, China to Tokyo, Japan from January 28 to February 17, 2020.

Multiple countries have reported evacuation missions to repatriate their citizens in the early phase of the emergence of COVID-19 from China. However, a paucity of data exists on how to optimally execute an evacuation while balancing the risk of transmission during the flight and avoiding spread to the evacuees' home countries. We describe the collective findings of the flight evacuation mission from Wuhan, China to Tokyo, Japan from January 28 to February 17, 2020. The evacuation team established the evacuation processing flow, including a focused health questionnaire, temperature monitoring, ticketing and check-in, and boarding procedure planning. The evacuees were seated according to pre-planned zones. Additionally, to facilitate the triage of evacuees for medical needs, we conducted in-flight quarantine to determine the disposition of the evacuees. All evacuees, regardless of their health condition, were required to perform rigorous hand hygiene frequently and to wear surgical masks throughout the flight. We implemented strict infection prevention and control throughout the mission, including in-flight quarantine. The pre-planned protocol and vigilant observation during the flight were crucial elements of this mission. Our experience is of value in developing a more refined plan for the next outbreak.

Why participation in an international clinical trial platform matters during a pandemic? Launching REMAP-CAP in Japan.

REMAP-CAP, a randomized, embedded, multifactorial adaptive platform trial for community-acquired pneumonia, is an international clinical trial that is rapidly expanding its scope and scale in response to the COVID-19 pandemic. Japan is now joining REMAP-CAP with endorsement from Japanese academic societies. Commitment to REMAP-CAP can significantly contribute to population health through timely identification of optimal COVID-19 therapeutics. Additionally, it will promote the establishment of a national and global network of clinical trials to tackle future pandemics of emerging and re-emerging infectious diseases, in collaboration with multiple stakeholders, including front-line healthcare workers, governmental agencies, regulatory authorities, and academic societies.

Clusters of Coronavirus Disease in Communities, Japan, January-April 2020.

We analyzed 3,184 cases of coronavirus disease in Japan and identified 61 case-clusters in healthcare and other care facilities, restaurants and bars, workplaces, and music events. We also identified 22 probable primary case-patients for the clusters; most were 20-39 years of age and presymptomatic or asymptomatic at virus transmission.

Does COVID-19 infection impact on the trend of seasonal influenza infection? 11 countries and regions, from 2014 to 2020.

OBJECTIVES: Infection due to the 2019 novel coronavirus disease (COVID-19) is dramatically widespread around the world. The COVID-19 pandemic could increase public concern to prevent infectious disease. The present study aimed to assess the relationship between the COVID-19 epidemic and the potential decrease in seasonal influenza cases. METHODS: This study was performed to show trends in seasonal influenza cases from the 2014-2015 season to the 2019-2020 season in 11 countries and regions, and evaluate whether the trends in the 2019-2020 season were different before and after the COVID-19 pandemic compared to previous seasons using a quasi-experimental difference-in-difference design. RESULTS: In East Asia, the number of seasonal influenza cases in the 2019-20 season was lower after the COVID-19 transmission compared to previous years. However, this was not the case in American countries or in European countries. CONCLUSION: The COVID-19 epidemic might have altered health behaviors, resulting in an unexpected reduction of seasonal influenza cases.