Association of Individual Behaviors With Infection Prevention Measures and COVID-19 Development: A Japanese Cross-Sectional Study.

During the COVID-19 pandemic, people often modified their behaviors and performed individual infection control practices despite the uncertain effectiveness of these in preventing COVID-19. A cross-sectional study using a nationwide internet survey (Japan COVID-19 Society Internet Survey) was conducted from September 2022 through October 2022. The questionnaire consisted of individual-level social distancing behaviors and infection prevention measures, and COVID-19 vaccination status. A multivariate logistic regression was performed to determine factors associated with the diagnosis of COVID-19 in the last two months of the survey date. In total, 19,296 respondents were selected for the primary analysis. Of 19,296 respondents, those with COVID-19 diagnosed in the last two months were 1,909 (9.9%). Factors independently associated with a recent history of COVID-19 were meeting colleagues in person ≧ 1 per week (adjusted odds ratio [aOR] 1.72). The response of "never or rarely" to the question of taking out (i.e., dining in) foods was marginally associated with a recent history of COVID-19 (aOR 1.27). Most individual, infection prevention practices and behavioral modifications during the omicron variant phase of the pandemic did not substantially impact COVID-19 prevention in the community.

Usefulness of a pluralistic approach in sentinel surveillance: seasonal influenza activity based on case counts per sentinel site in the National Epidemiological Surveillance of Infectious Diseases Program and test counts, case counts, and test positivity from the National Hospital Organization.

In Japan, based on the National Epidemiological Surveillance of Infectious Diseases (NESID) Program, influenza cases from ~5,000 sentinel sites are monitored weekly as part of influenza surveillance (as number of influenza cases/sentinel site). One limitation is that the number of influenza tests conducted is not reported. Separately, the National Hospital Organization (NHO), with ~140 hospitals, routinely publishes three indicators: number of influenza tests, influenza-positive case counts, and test positivity. We used NESID and NHO data from April 2011 to June 2022 to assess the usefulness of multiple indicators to monitor influenza activity. Temporal trends of the NHO and NESID indicators were similar, and NHO indicator levels well-correlated with those of the NESID indicator. Influenza positivity in the NHO data, however, showed an earlier rise and peak time compared to the NESID indicator. Importantly, through the non-epidemic summer periods and the coronavirus disease 2019 pandemic, a sizable number of influenza tests continued to be done at NHO hospitals, with results showing considerably low case counts and test positivity. These data show that a relatively small number of sentinel sites is sufficient to monitor influenza activity nationally, and, that utilizing multiple indicators can increase our confidence in situational awareness and data interpretations.

Prevalence and trends in persistent symptoms following COVID-19 in Japan: A nationwide cross-sectional survey.

INTRODUCTION: Even during the endemic phase of the COVID-19 pandemic, the impact of persistent symptoms on patients and healthcare systems remains significant. Thus, a more comprehensive understanding of these symptoms is essential. METHODS: Using data from the Japan Society and New Tobacco Internet Survey conducted in February 2023, this cross-sectional study investigated the prevalence of, and changes in, persistent COVID-19 symptoms. RESULTS: In total, 21,108 individuals responded to the survey. Of these, 29.1 % (6143) had a history of COVID-19. Our analysis found that arm/leg/joint pain (adjusted odds ratio [aOR]: 1.17; 95 % confidence interval [95 % CI]: 1.03-1.33), back pain (aOR: 1.13; 95 % CI: 1.01-1.27), chest pain (aOR: 1.53; 95 % CI: 1.20-1.96), malaise (aOR: 1.14; 95 % CI: 1.02-1.28), loss of taste (aOR: 2.55; 95 % CI: 1.75-3.72), loss of smell (aOR: 2.33; 95 % CI: 1.67-3.26), memory impairment (aOR: 1.27; 95 % CI: 1.04-1.56), and cough (aOR: 1.72; 95 % CI: 1.38-2.13) were independently associated with a history of COVID-19 contracted more than two months but less than six months previously. Further, back pain (aOR: 1.24; 95 % CI: 1.04-1.47) and loss of taste (aOR: 2.28; 95 % CI: 1.24-4.21) showed independent association with COVID-19 contracted more than 12 months previously. CONCLUSIONS: Various symptoms were independently associated with a history of COVID-19. While most patients tend to recover within a year after contracting COVID-19, certain symptoms, such as back pain and loss of taste, persist longer than a year, underscoring public health concerns and emphasizing the need for health care services to support patients suffering from persistent symptoms.

Molecular Epidemiology of Respiratory Syncytial Virus during 2019-2022 and Surviving Genotypes after the COVID-19 Pandemic in Japan.

To evaluate the changes in respiratory syncytial virus (RSV) collected between 2019 and 2022, we analyzed RSV-A and RSV-B strains from various prefectures in Japan before and after the COVID-19 pandemic. RT-PCR-positive samples collected from children with rapid test positivity at outpatient clinics in 11 prefectures in Japan were sequenced for the ectodomain of the G gene to determine the genotype. Time-aware phylogeographic analyses were performed using the second hypervariable region (HVR) of the G gene from 2012 to 2022. Of 967 samples, 739 (76.4%) were found to be RSV-positive using RT-PCR. RSV peaked in September 2019 but was not detected in 2020, except in Okinawa. Nationwide epidemics occurred with peaks in July 2021 and 2022. The genotype remained the same, ON1 for RSV-A and BA9 for RSV-B during 2019-2022. Phylogeographic analysis of HVR revealed that at least seven clusters of RSV-A had circulated previously but decreased to two clusters after the pandemic, whereas RSV-B had a single monophyletic cluster over the 10 years. Both RSV-A and RSV-B were transferred from Okinawa into other prefectures after the pandemic. The RSV epidemic was suppressed due to pandemic restrictions; however, pre-pandemic genotypes spread nationwide after the pandemic.

Drug effectiveness for COVID-19 inpatients inferred from Japanese medical claim data using propensity score matching.

Background: Earlier studies and clinical trials of Coronavirus 2019 (COVID-19) showed that drugs such as antiviral drugs, antibody cocktails, and steroids and anti-inflammatory drugs can prevent severe outcomes and death. Methods: Observational data in Japan assess drug effectiveness against COVID-19. We applied the average treatment effect model, particularly propensity scoring, which can treat the choice of administered drug as if administration were randomly assigned to inpatients. Data of the Medical Information Analysis Databank, operated by National Hospital Organization in Japan, were used. The outcome was defined as mortality. Subjects were all inpatients, inpatients with oxygen administration, and inpatients using respiratory ventilation, classified by three age classes: all ages, 65 years old or older, and younger than 65 years old. Information about demographic characteristics, underlying disease, administered drug, the proportions of Alpha, Beta and Omicron variant strains, and vaccine coverage were used as explanatory variables for logistic regression. Results: Estimated results indicated that only one antibody cocktail (sotrovimab, casirivimab and imdevimab) was associated with raising the probability of survival consistently and significantly. By contrast, other drugs, an antiviral drug (remdesivir), a steroid (dexamethasone), and an anti-inflammatory drug (baricitinib and tocilizumab) were related to reduce the probability of survival. However, propensity score matching method might engender biased results because of a lack of data such as detailed information related to intervention and potential confounders. Therefore, the effectiveness of some drugs might not be evaluated properly in this study. Conclusions: Results indicate high likelihood that antibody cocktails were consistently associated with high probability of survival, although low likelihood was found for other drugs for older patients with mild to severe severity and all age patients with moderate severity. Further study is necessary in light of the lack of available data.