Whole-Genome Analysis of Influenza A(H3N2) and B/Victoria Viruses Detected in Myanmar during the COVID-19 Pandemic in 2021.

An influenza circulation was observed in Myanmar between October and November in 2021. Patients with symptoms of influenza-like illness were screened using rapid diagnostic test (RDT) kits, and 147/414 (35.5%) upper respiratory tract specimens presented positive results. All RDT-positive samples were screened by a commercial multiplex real-time polymerase chain reaction (RT-PCR) assay, and 30 samples positive for influenza A(H3N2) or B underwent further typing/subtyping for cycle threshold (Ct) value determination based on cycling probe RT-PCR. The majority of subtyped samples (n = 13) were influenza A(H3N2), while only three were B/Victoria. Clinical samples with low Ct values obtained by RT-PCR were used for whole-genome sequencing via next-generation sequencing technology. All collected viruses were distinct from the Southern Hemisphere vaccine strains of the corresponding season but matched with vaccines of the following season. Influenza A(H3N2) strains from Myanmar belonged to clade 2a.3 and shared the highest genetic proximity with Bahraini strains. B/Victoria viruses belonged to clade V1A.3a.2 and were genetically similar to Bangladeshi strains. This study highlights the importance of performing influenza virus surveillance with genetic characterization of the influenza virus in Myanmar, to contribute to global influenza surveillance during the COVID-19 pandemic.

Assessing the Pre-Vaccination Anti-SARS-CoV-2 IgG Seroprevalence among Residents and Staff in Nursing Home in Niigata, Japan, November 2020.

An outbreak of coronavirus disease 2019 (COVID-19) occurred in a nursing home in Niigata, Japan, November 2020, with an attack rate of 32.0% (63/197). The present study was aimed at assessing the pre-vaccination seroprevalence almost half a year after the COVID-19 outbreak in residents and staff in the facility, along with an assessment of the performance of the enzyme-linked immunosorbent assay (ELISA) and the chemiluminescent immunoassay (CLIA), regarding test seropositivity and seronegativity in detecting immunoglobulin G (IgG) anti-severe acute respiratory syndrome 2 (SARS-CoV-2) antibodies (anti-nucleocapsid (N) and spike (S) proteins). A total of 101 people (30 reverse transcription PCR (RT-PCR)-positive and 71 RT-PCR-negative at the time of the outbreak in November 2020) were tested for anti-IgG antibody titers in April 2021, and the seroprevalence was approximately 40.0-60.0% for residents and 10.0-20.0% for staff, which was almost consistent with the RT-PCR test results that were implemented during the outbreak. The seropositivity for anti-S antibodies showed 90.0% and was almost identical to the RT-PCR positives even after approximately six months of infections, suggesting that the anti-S antibody titer test is reliable for a close assessment of the infection history. Meanwhile, seropositivity for anti-N antibodies was relatively low, at 66.7%. There was one staff member and one resident that were RT-PCR-negative but seropositive for both anti-S and anti-N antibody, indicating overlooked infections despite periodical RT-PCR testing at the time of the outbreak. Our study indicated the impact of transmission of SARS-CoV-2 in a vulnerable elderly nursing home in the pre-vaccination period and the value of a serological study to supplement RT-PCR results retrospectively.

The Relative Roles of Ambient Temperature and Mobility Patterns in Shaping the Transmission Heterogeneity of SARS-CoV-2 in Japan.

We assess the effects of ambient temperature and mobility patterns on the transmissibility of COVID-19 during the epidemiological years of the pandemic in Japan. The prefecture-specific daily time-series of confirmed coronavirus disease 2019 (COVID-19) cases, meteorological variables, levels of retail and recreation mobility (e.g., activities, going to restaurants, cafes, and shopping centers), and the number of vaccinations were collected for six prefectures in Japan from 1 May 2020 to 31 March 2022. We combined standard time-series generalized additive models (GAMs) with a distributed lag non-linear model (DLNM) to determine the exposure-lag-response association between the time-varying effective reproductive number (Rt), ambient temperature, and retail and recreation mobility, while controlling for a wide range of potential confounders. Utilizing a statistical model, the first distribution of the mean ambient temperature (i.e., -4.9 °C) was associated with an 11.6% (95% confidence interval [CI]: 5.9-17.7%) increase in Rt compared to the optimum ambient temperature (i.e., 18.5 °C). A retail and recreation mobility of 10.0% (99th percentile) was associated with a 19.6% (95% CI: 12.6-27.1%) increase in Rt over the optimal level (i.e., -16.0%). Our findings provide a better understanding of how ambient temperature and mobility patterns shape severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission. These findings provide valuable epidemiological insights for public health policies in controlling disease transmission.

Was the Reduction in Seasonal Influenza Transmission during 2020 Attributable to Non-Pharmaceutical Interventions to Contain Coronavirus Disease 2019 (COVID-19) in Japan?

We quantified the effects of adherence to various non-pharmaceutical interventions (NPIs) on the seasonal influenza epidemic dynamics in Japan during 2020. The total monthly number of seasonal influenza cases per sentinel site (seasonal influenza activity) reported to the National Epidemiological Surveillance of Infectious Diseases and alternative NPI indicators (retail sales of hand hygiene products and number of airline passenger arrivals) from 2014-2020 were collected. The average number of monthly seasonal influenza cases in 2020 had decreased by approximately 66.0% (p < 0.001) compared to those in the preceding six years. An increase in retail sales of hand hygiene products of ¥1 billion over a 3-month period led to a 15.5% (95% confidence interval [CI]: 10.9-20.0%; p < 0.001) reduction in seasonal influenza activity. An increase in the average of one million domestic and international airline passenger arrivals had a significant association with seasonal influenza activity by 11.6% at lag 0-2 months (95% CI: 6.70-16.5%; p < 0.001) and 30.9% at lag 0-2 months (95% CI: 20.9-40.9%; p < 0.001). NPI adherence was associated with decreased seasonal influenza activity during the COVID-19 pandemic in Japan, which has crucial implications for planning public health interventions to minimize the health consequences of adverse seasonal influenza epidemics.

Persistence of Mental Health Deterioration Among People Living Alone During the COVID-19 Pandemic: A Periodically-repeated Longitudinal Study.

BACKGROUND: This longitudinal study aimed to investigate how psychological distress levels changed from early to middle phases of the new coronavirus (COVID-19) pandemic depending on the living arrangements of individuals. METHODS: An internet-based, longitudinal survey of 2,400 Japanese people was conducted every 5-6 weeks between February 2020 and January 2021. The presence of severe psychological distress (SPD) was measured using the Kessler's psychological distress scale. Living arrangements were classified into two groups (ie, living alone or living with others). Mixed-effects logistic regression analysis was performed to assess whether changes in SPD status were different depending on living arrangements. RESULTS: Of 2,400 respondents, 446 (18.5%) lived alone. Although the proportion of SPD in both individuals living alone and those living with others increased to the same extent in the early phase of the pandemic, the distress levels decreased after the early phase of the pandemic in the group living with others, compared with the group living alone, for which SPD remained high. The odds ratio (OR) of developing SPD in interaction term with survey phases tended to be higher among those who lived alone than those who lived with others in Phase 6 (OR 1.89; 95% confidence interval [CI], 0.99-3.64) and Phase 7 (OR 1.88; 95% CI, 0.97-3.63). CONCLUSION: During the COVID-19 pandemic, those living alone are persistently at a higher risk of SPD compared to those living with others. Effective countermeasures targeting those living alone, such as enhancing online communication or providing psychological therapies, are essential.

Individual-level social capital and COVID-19 vaccine hesitancy in Japan: a cross-sectional study.

To reduce vaccine hesitancy, it is important to identify factors that can intervene at the individual or community level. Social capital is a possible factor because it is associated with various vaccine hesitancy, such as for measles and influenza. However, limited studies have explored the association between social capital and vaccination for COVID-19, which is an unprecedented pandemic and infodemic. Therefore, this study aimed to clarify the association between social capital and COVID-19 vaccination during the pandemic. This cross-sectional study used quota sampling for an online-based survey. Participants were asked whether they had previously been vaccinated for COVID-19 and their intention to receive a COVID-19 vaccine booster. Social capital was evaluated using three measures (individual-level civic participation, social cohesion, and reciprocity). Multiple logistic regression analysis was performed to clarify the association between social capital and previous COVID-19 vaccination status as well as intention to receive a COVID-19 booster. Participants were 2,313 individuals, of whom 87.2% had received a COVID-19 vaccine; 72.3% intended to obtain a COVID-19 booster. Individuals with any social capital are more likely to receive a COVID-19 vaccination than those with none (OR: 1.73, 95%CI: 1.18-2.54; OR: 1.58, 95%CI: 1.22-2.05; OR: 3.05, 95%CI: 2.15-4.33). These indicators were also associated with the intention to receive a COVID-19 booster. Thus, our results suggest that among the general public, those with individual-level social capital are more likely to receive a COVID-19 vaccination than those with none. Social capital may be a factor that can reduce vaccine hesitancy during a pandemic.

Household Secondary Transmission of the Severe Acute Respiratory Syndrome Coronavirus 2 Alpha Variant From a Community Cluster in a Nursery in Japan.

BACKGROUND: Spread of variants of concerns (VOCs) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has led to an increase in children with coronavirus disease 2019 (COVID-19). In February 2021, clusters of the Alpha variant of SARS-CoV-2 started to be reported in Niigata, Japan, including a large nursery cluster. We investigated the transmission routes and household secondary attack rates (SARs) in this cluster. METHODS: Epidemiologic data related to a nursery cluster in Niigata, Japan, particularly child-origin and adult-origin SARs, were analyzed. VOCs were confirmed by whole-genome sequencing of virus from patients. RESULTS: In total, 42 persons (22 children and 20 adults) in the cluster were infected with the Alpha variant. In the nursery, 13 of 81 children (16.0%) and 4 of 24 teachers (16.7%) were infected. SARS-CoV-2 later spread to 25 persons (10 children and 15 adults) outside the nursery. Child-origin and adult-origin household SARs were 27.7% (13/47) and 47.0% (8/17) ( P = 0.11), respectively, which were higher than rates attributable to non-VOCs in previous studies. CONCLUSIONS: As compared with non-VOCs, the Alpha variant of SARS-CoV-2 exhibited high transmissibility among children and adults and may pose a high risk for household secondary transmission from SARS-CoV-2-infected children. Increased transmissibility of current or future VOCs could lead to greater transmission from children to adults or other children.

An exploration of the political, social, economic and cultural factors affecting how different global regions initially reacted to the COVID-19 pandemic.

Responses to the early (February-July 2020) COVID-19 pandemic varied widely, globally. Reasons for this are multiple but likely relate to the healthcare and financial resources then available, and the degree of trust in, and economic support provided by, national governments. Cultural factors also affected how different populations reacted to the various pandemic restrictions, like masking, social distancing and self-isolation or self-quarantine. The degree of compliance with these measures depended on how much individuals valued their needs and liberties over those of their society. Thus, several themes may be relevant when comparing pandemic responses across different regions. East and Southeast Asian populations tended to be more collectivist and self-sacrificing, responding quickly to early signs of the pandemic and readily complied with most restrictions to control its spread. Australasian, Eastern European, Scandinavian, some Middle Eastern, African and South American countries also responded promptly by imposing restrictions of varying severity, due to concerns for their wider society, including for some, the fragility of their healthcare systems. Western European and North American countries, with well-resourced healthcare systems, initially reacted more slowly, partly in an effort to maintain their economies but also to delay imposing pandemic restrictions that limited the personal freedoms of their citizens.

Epidemiology and Genetic Analysis of SARS-CoV-2 in Myanmar during the Community Outbreaks in 2020.

We aimed to analyze the situation of the first two epidemic waves in Myanmar using the publicly available daily situation of COVID-19 and whole-genome sequencing data of SARS-CoV-2. From March 23 to December 31, 2020, there were 33,917 confirmed cases and 741 deaths in Myanmar (case fatality rate of 2.18%). The first wave in Myanmar from March to July was linked to overseas travel, and then a second wave started from Rakhine State, a western border state, leading to the second wave spreading countrywide in Myanmar from August to December 2020. The estimated effective reproductive number (Rt) nationwide reached 6-8 at the beginning of each wave and gradually decreased as the epidemic spread to the community. The whole-genome analysis of 10 Myanmar SARS-CoV-2 strains together with 31 previously registered strains showed that the first wave was caused by GISAID clade O or PANGOLIN lineage B.6 and the second wave was changed to clade GH or lineage B.1.36.16 with a close genetic relationship with other South Asian strains. Constant monitoring of epidemiological situations combined with SARS-CoV-2 genome analysis is important for adjusting public health measures to mitigate the community transmissions of COVID-19.

Genomic Epidemiology Reveals Multiple Introductions of Severe Acute Respiratory Syndrome Coronavirus 2 in Niigata City, Japan, Between February and May 2020.

The coronavirus disease 2019 (COVID-19) has caused a serious disease burden and poses a tremendous public health challenge worldwide. Here, we report a comprehensive epidemiological and genomic analysis of SARS-CoV-2 from 63 patients in Niigata City, a medium-sized Japanese city, during the early phase of the pandemic, between February and May 2020. Among the 63 patients, 32 (51%) were female, with a mean (±standard deviation) age of 47.9 ± 22.3 years. Fever (65%, 41/63), malaise (51%, 32/63), and cough (35%, 22/63) were the most common clinical symptoms. The median C t value after the onset of symptoms lowered within 9 days at 20.9 cycles (interquartile range, 17-26 cycles), but after 10 days, the median C t value exceeded 30 cycles (p < 0.001). Of the 63 cases, 27 were distributed in the first epidemic wave and 33 in the second, and between the two waves, three cases from abroad were identified. The first wave was epidemiologically characterized by a single cluster related to indoor sports activity spread in closed settings, which included mixing indoors with families, relatives, and colleagues. The second wave showed more epidemiologically diversified events, with most index cases not related to each other. Almost all secondary cases were infected by droplets or aerosols from closed indoor settings, but at least two cases in the first wave were suspected to be contact infections. Results of the genomic analysis identified two possible clusters in Niigata City, the first of which was attributed to clade S (19B by Nexstrain clade) with a monophyletic group derived from the Wuhan prototype strain but that of the second wave was polyphyletic suggesting multiple introductions, and the clade was changed to GR (20B), which mainly spread in Europe in early 2020. These findings depict characteristics of SARS-CoV-2 transmission in the early stages in local community settings during February to May 2020 in Japan, and this integrated approach of epidemiological and genomic analysis may provide valuable information for public health policy decision-making for successful containment of chains of infection.

Coronavirus Disease 2019 Cluster Originating in a Primary School Teachers' Room in Japan.

BACKGROUND: School closures are a subject of debate during the present coronavirus disease 2019 (COVID-19) pandemic. Because children are not the main driver of COVID-19 transmission in the community, school education must be prioritized in conjunction with appropriate infection prevention and control measures, as determined by local COVID-19 incidence. METHODS: We investigated the causes and transmission routes of a primary school cluster of COVID-19 that occurred during November and December 2020 in Niigata, Japan. RESULTS: In the cluster, the virus spread among teachers, then from teachers to students, and then to their family members. This primary school cluster comprised 26 infected patients and included teachers (13/33, 39%), students (9/211, 4%), and family members (4/65, 6%). The secondary attack rate from the 3 index teachers to the remaining 30 teachers was 33%; however, the rate to students was only 4%. Factors contributing to cluster formation include the fact that 2 of the index teachers continued working while symptomatic and that the environment and infection prevention measures in the teachers' room were inadequate. CONCLUSIONS: To open schools safely and without interruption, adequate measures to prevent COVID-19 infection in schools should be emphasized not only for children but also for teachers and their environment.

Trends in COVID-19 vaccination intent from pre- to post-COVID-19 vaccine distribution and their associations with the 5C psychological antecedents of vaccination by sex and age in Japan.

Vaccine hesitancy regarding the coronavirus disease 2019 (COVID-19) vaccine is widespread during the COVID-19 pandemic. Many recent studies have reported that the confidence of the vaccination and perceived risk were associated with vaccination intent, yet few studies have focused on other psychological factors. This study aimed to clarify the trends in COVID-19 vaccination intent and to identify the association between the 5C psychological antecedents and COVID-19 vaccination intent by sex and age in Japan. This was a longitudinal study conducted through an Internet-based survey from January 2021 to April 2021 before and after vaccine distribution in Japan, including 2,655 participants recruited by quota sampling. Participants were asked to indicate how likely they were to get vaccinated against COVID-19. In the second survey, the participants responded to questions regarding the 5C psychological antecedents: confidence, complacency, constraints (structural and psychological barriers), calculation (engagement in extensive information searching), and collective responsibility (willingness to protect others). Multiple logistic regression analysis was performed to clarify the association between the 5C psychological antecedents and COVID-19 vaccination intent in the second wave survey. COVID-19 vaccination intent improved from 62.1% to 72.4% after vaccine distribution, but no significant difference was found in young men. Confidence and collective responsibility were positively associated with vaccination intent, and calculation was negatively associated among all generations. COVID-19 vaccination intent may be affected not only by confidence and constraints but also by calculation and collective responsibility, and further research is needed.

How Frequently Do Ordinary Citizens Practice Hand Hygiene at Appropriate Moments during the COVID-19 Pandemic in Japan?

We aimed to clarify the status of hand hygiene practices among ordinary citizens during the COVID-19 pandemic in Japan, as well as the frequency of daily hand hygiene as an indicator of education and evaluation. This cross-sectional study was based on an internet survey completed by 2,149 participants (age range: 20-79 years, men: 51.0%, response rate: 89.5%), selected from June 23 to 28, 2020. The participants responded regarding the frequency of implementing hand hygiene at 5 moments (after returning from a public place, after using the toilet, after touching something outside, before eating food, and after blowing the nose, coughing, or sneezing). Additionally, the participants responded to the number of daily hand hygiene events. The cutoff value of the total number of daily hand hygiene events to determine whether hand hygiene was performed at all 5 time points was determined using receiver operating characteristic analysis. The mean number of hand hygiene events was 10.2 times/day. The prevalence of implementing hand hygiene at each moment ranged from 30.2% to 76.4%; only 21.1% of respondents practiced hand hygiene at all times. Both Youden Index and specificity were high when the cut-off value was 11 times/day. Therefore, the criterion of hand hygiene (≥11 times/day) may be useful in education and evaluation.

Survey on usage and concerns of a COVID-19 contact tracing application in Japan.

OBJECTIVES: We aimed to identify the concerns, current implementation status and correct usage, and factors inhibiting implementation and correct use of a COVID-19 contact tracing application among the ordinary citizens in Japan. STUDY DESIGN: This was a cross-sectional study based on an internet survey completed by 2013 participants who were selected among registrants of an Internet research company between September 8 and 13, 2020. METHODS: Participants completed an online survey that included thoughts and concerns about the application, status of use, and questions about whether the application was being used correctly. We performed multiple logistic regression analysis to clarify the association between the use of the app and sociodemographic factors and user concerns. RESULTS: Of the 2013 respondents, 429 (21.3%) participants reported using this application, but only 60.8% of them used it correctly. The percentage of those having some concerns about the application ranged from 45.9% to 75.5%, with the highest percentage being 'doubts about effectiveness of apps for preventing spread of infection'. Multiple logistic regression analysis revealed, the main concerns inhibiting application use were insufficient knowledge of how to use it, privacy concerns, doubts about the effectiveness of the app, and concerns about battery consumption and communication costs. Additionally, the prevalence of the application was lower for lower-income individuals. CONCLUSIONS: The findings suggest that income may create inequalities in the efficacy and effectiveness of COVID-19 contact tracing applications. Awareness activity strategies to dispel such concerns and support low-income individuals may be needed.

Shifts in the epidemic season of human respiratory syncytial virus associated with inbound overseas travelers and meteorological conditions in Japan, 2014-2017: An ecological study.

Few studies have examined the effects of inbound overseas travelers and meteorological conditions on the shift in human respiratory syncytial virus (HRSV) season in Japan. This study aims to test whether the number of inbound overseas travelers and meteorological conditions are associated with the onset week of HRSV epidemic season. The estimation of onset week for 46 prefectures (except for Okinawa prefecture) in Japan for 4-year period (2014-2017) was obtained from previous papers based on the national surveillance data. We obtained data on the yearly number of inbound overseas travelers and meteorological (yearly mean temperature and relative humidity) conditions from Japan National Tourism Organization (JNTO) and Japan Meteorological Agency (JMA), respectively. Multi-level mixed-effects linear regression analysis showed that every 1 person (per 100,000 population) increase in number of overall inbound overseas travelers led to an earlier onset week of HRSV epidemic season in the year by 0.02 week (coefficient -0.02; P<0.01). Higher mean temperature and higher relative humidity were also found to contribute to an earlier onset week by 0.30 week (coefficient -0.30; P<0.05) and 0.18 week (coefficient -0.18; P<0.01), respectively. Additionally, models that included the number of travelers from individual countries (Taiwan, South Korea, and China) except Australia showed that both the number of travelers from each country and meteorological conditions contributed to an earlier onset week. Our analysis showed the earlier onset week of HRSV epidemic season in Japan is associated with increased number of inbound overseas travelers, higher mean temperature, and relative humidity. The impact of international travelers on seasonality of HRSV can be further extended to investigations on the changes of various respiratory infectious diseases especially after the coronavirus disease 2019 (COVID-19) pandemic.

Acceptance of a COVID-19 Vaccine in Japan during the COVID-19 Pandemic.

Vaccination could be a key protective measure against coronavirus disease 2019 (COVID-19), and it is important to understand the acceptability of the COVID-19 vaccine among the general public. However, there is no study on the acceptance of a COVID-19 vaccine in Japan. Therefore, this study aimed to describe the COVID-19 vaccine acceptance and hesitancy situation in Japan and assess the factors associated with such issues. This was a cross-sectional study based on an internet survey completed by 2956 people. Participants were asked to indicate how likely they were to get vaccinated for COVID-19. In addition, the participants responded to questions regarding sociodemographic factors, attitudes, and beliefs regarding COVID-19 infection and vaccination. The proportion of participants with a high likelihood of getting a COVID-19 vaccine was 62.1%. Multiple logistic regression analysis showed that vaccine acceptance was lower among several sociodemographic groups, such as women, adults aged 20-49 years, and those with a low-income level. Several psychological factors, especially the perceived effectiveness of the COVID-19 vaccine, and willingness to protect others by getting oneself vaccinated, were associated with vaccine acceptance. Our results indicate that the perceived effectiveness of the vaccine and willingness to protect others may play an important role in the acceptance of the COVID-19 vaccine.

Development of severe psychological distress among low-income individuals during the COVID-19 pandemic: longitudinal study.

BACKGROUND: It has been indicated that the health impact of COVID-19 is potentially greater in individuals from lower socioeconomic status than in the overall population. AIMS: To examine how the spread of COVID-19 has altered the general public's mental health, and whether such changes differ in relation to individual income. METHOD: An online longitudinal survey was conducted at three different time periods during the pandemic. We recruited 1993 people aged 20-70 years, living in the Tokyo metropolitan area in Japan. Participants' mental health was measured with the six-item version of the Kessler Psychological Distress Scale; the existence of severe psychological distress was ascertained through the cut-off data. Multiple logistic and mixed-model ordinal logistic regression analyses were performed, with income as the independent variable. RESULTS: Of the participants, 985 were male, with a mean age of 50.5 (±15.8) years. Severe psychological distress percentages for each tested period were 9.3%, 11.2% and 10.7% for phases 1, 2 and 3, respectively. Between phases 1 and 2 or phases 2 and 3, the group that earned <£15 000 had significantly higher propensity to develop severe psychological distress than the group that earned ≥£45 000 (odds ratio 2.09, 95% CI 0.95-4.56 between phases 1 and 2; odds ratio 3.00, 95% CI 1.01-9.58 between phases 2 and 3). CONCLUSIONS: Although there has been significant deterioration in mental health among citizens during the COVID-19 pandemic, this was more significant among those with lower income. Therefore, mental health measures that focus on low socioeconomic groups may be necessary.

Changes in Psychological Distress During the COVID-19 Pandemic in Japan: A Longitudinal Study.

BACKGROUND: This longitudinal study aimed to examine the changes in psychological distress of the general public from the early to community-transmission phases of the COVID-19 pandemic and to investigate the factors related to these changes. METHODS: An internet-based survey of 2,400 Japanese people was conducted in two phases: early phase (baseline survey: February 25-27, 2020) and community-transmission phase (follow-up survey: April 1-6, 2020). The presence of severe psychological distress (SPD) was measured using the Kessler's Six-scale Psychological Distress Scale. The difference of SPD percentages between the two phases was examined. Mixed-effects ordinal logistic regression analysis was performed to assess the factors associated with the change of SPD status between the two phases. RESULTS: Surveys for both phases had 2,078 valid respondents (49.3% men; average age, 50.3 years). In the two surveys, individuals with SPD were 9.3% and 11.3%, respectively, demonstrating a significant increase between the two phases (P = 0.005). Significantly higher likelihood to develop SPD were observed among those in lower (ie, 18,600-37,200 United States dollars [USD], odds ratio [OR] 1.95; 95% confidence interval [CI], 1.10-3.46) and the lowest income category (ie, <18,600 USD, OR 2.12; 95% CI, 1.16-3.86). Furthermore, those with respiratory diseases were more likely to develop SPD (OR 2.56; 95% CI, 1.51-4.34). CONCLUSIONS: From the early to community-transmission phases of COVID-19, psychological distress increased among the Japanese. Recommendations include implementing mental health measures together with protective measures against COVID-19 infection, prioritizing low-income people and those with underlying diseases.

Incorrect Use of Face Masks during the Current COVID-19 Pandemic among the General Public in Japan.

Since the emergence of the COVID-19 pandemic, the use of face masks by healthy individuals for prevention has been attracting public attention. However, efficacy depends on proper usage. We set out to determine the prevalence of wearing masks to prevent COVID-19 and compliance with appropriate measures for the correct use of face masks among the general public in Japan where wearing medical masks is a "cultural" normality. This cross-sectional study was based on an internet-based survey completed by 2141 people (50.8% men, aged 20-79 years) who were selected among registrants of an Internet research company between 1 April and 6 April 2020. Participants were asked to indicate how often they wore masks for prevention and to what extent they practiced appropriate measures suggested by the World Health Organization. The prevalence of wearing masks was 80.9% and compliance rates with appropriate measures ranged from 38.3% to 83.5%. Only 23.1% complied with all recommendations. Compliance rates were overall low in men and persons with low household incomes. Our results, hence show that many citizens implement inaccurate measures when using face masks. Therefore, providing guidance on correct usage is essential when encouraging the use of face masks to prevent COVID-19.

Geographic Correlation between the Number of COVID-19 Cases and the Number of Overseas Travelers in Japan, Jan-Feb, 2020.

Since the coronavirus disease 2019 (COVID-19) emerged in Wuhan, China, in December 2019, it has rapidly spread worldwide, and the number of cases is also increasing in Japan. The number of COVID-19 cases in Japan in the early stages was not uniform, and cases were largely concentrated in several prefectures. There was a strong, positive correlation between the distribution of COVID-19 cases and the number of foreign travelers as well as Chinese travelers, at prefectural level, with coefficients of 0.68 (P < 0.0001) and 0.60 (P < 0.0001), respectively. Moreover, phylogenetic tree analysis revealed that all the registered SARS-CoV-2 detected from January 23 to February 29, 2020, belonged to Chinese lineage, while those detected in March 2020 belonged to American and European lineages. Only 14 (20.3%) were infected outside Japan; however, the majority of the cases (79.7%) were infected domestically. In conclusion, a higher number of COVID-19 cases were identified in prefectures with more Chinese travelers, supporting the importance of enforcing policies that restrict the entry of overseas travelers to control COVID-19 spread. These findings highlight the risk of secondary transmission in the community caused by apparent or silently imported cases.