Association of COVID-19 preventive behavior and job-related stress with the sleep quality of healthcare workers one year into the COVID-19 outbreak: a Japanese cross-sectional survey.

BACKGROUND: This study aimed to evaluate the association of COVID-19 preventive behavior and job-related stress with sleep quality among healthcare workers (HCWs). We conducted a cross-sectional survey using a questionnaire at the National Center of Neurology and Psychiatry, Tokyo, Japan. METHODS: A total of 586 participants who completed the questionnaire were eligible for the study. The Pittsburgh Sleep Quality Index was used to evaluate sleep quality. We examined the level of engagement between poor sleep and COVID-19-related infection preventive behaviors, such as avoiding closed spaces, crowded places, and close contact (three Cs), a distance of at least one meter from others, wearing a face mask regularly, washing hands regularly, and working remotely, as well as job-related stress in the work environment, exposure to patients, potential risk of infection, fear of infecting others, need for social confinement, and financial instability. We conducted a hierarchical logistic regression analysis to examine the relationship between poor sleep and COVID-19 preventive behavior, job-related stress, and other covariates, including age, sex, and the Kessler Psychological Distress Scale (K6), which was used to measure non-specific psychological distress. RESULTS: Poor sleep was observed in 223 (38.1%) participants. Adherence to COVID-19 preventive measures was relatively high: 84.1% of participants answered "always" for wearing a face mask regularly and 83.4% for washing hands regularly. In the multivariate logistic regression analysis, stress in the work environment (odds ratio [OR] = 2.09, 95% confidence interval [CI], 1.37-3.20; p < 0.001), financial instability (OR = 1.73, 95% CI, 1.12-2.67; p < 0.05), and low adherence to working remotely (OR = 1.65, 95% CI, 1.06-2.57; p < 0.05) were independently and significantly associated with poor sleep after controlling for the covariates. CONCLUSIONS: One year into the COVID-19 pandemic, the poor sleep rates of HCWs remained high. These results emphasize the need to protect HCWs from work environment stress and financial concerns.

Association between health anxiety dimensions and preventive behaviors during the COVID-19 pandemic among Japanese healthcare workers.

Objective: Health anxiety (HA), defined as excessive worry about having a serious medical condition, may affect preventive behaviors during the coronavirus disease 2019 (COVID-19) pandemic. We examined the distinct role of two dimensions of HA-perceived likelihood (probability dimension) and awfulness of illness (awfulness dimension)-in self-protection, as reflected in preventive behaviors during the pandemic. Methods: Participants comprised 657 healthcare workers. Data were collected between February 24 and 26, 2021. The Short Health Anxiety Inventory determined the HA dimensions. Adherence to the government's recommendations for COVID-19 preventive behaviors was self-rated. An independent association between each HA dimension and participants' adherence to the recommendations was examined using multivariable regression. Results: Within the analyzed sample of 560 subjects, severe HA was observed in 9.1 %. The more the participants felt awful, the less frequently they engaged in the recommended preventive behaviors (adjusted odds ratio = 0.993, 95 % confidence interval: 0.989, 0.998, p = 0.003) regardless of their profession, working position, psychological distress, sleep disturbance, and current physical diseases. However, the probability dimension was not associated with their preventive behaviors. Conclusion: The awfulness dimension of HA could be a more sensitive marker of preventive behaviors than the probability dimension. Paying particular attention to the awfulness dimension may help optimize self-protection strategies during the COVID-19 pandemic. A two-dimensional understanding of HA may be useful for the maintenance of the healthcare system and public health as well as healthcare workers' own health.

The association between experience of COVID-19-related discrimination and psychological distress among healthcare workers for six national medical research centers in Japan.

BACKGROUND: Discrimination is an important determinant of negative mental health outcomes. This study determined the association between the experience of COVID-19-related discrimination and psychological distress among healthcare workers (HCWs) in Japan. METHODS: This cross-sectional study conducted a health survey among 5703 HCWs of six national medical and research centers in Japan from October 2020 to March 2021. COVID-19-related discrimination was defined either when participants or their family members were badmouthed or when they felt discriminated against in some way. We used the Kessler Psychological Distress Scale (K6) to assess the presence of severe psychological distress (≥ 13 points). We used logistic regression models to examine the association between discrimination and psychological distress. We also identified factors associated with discrimination. RESULTS: Of the participants, 484 (8.4%) reported COVID-19-related discrimination and 486 (8.5%) had severe psychological distress. HCWs who were female vs. male (adjusted odds ratio [AOR] = 1.41, 95% confidence interval [CI] = 1.28-1.55), had high vs. low viral exposure (AOR = 2.31, 95% CI = 1.81-2.93), and worked for 11 or more hours/day vs. 8 or less hours/day (AOR = 1.42, 95% CI = 1.35-1.49) were more likely to have experienced COVID-19-related discrimination. The AOR (95% CI) of severe psychological distress was 1.83 (1.29-2.59) among those who experienced discrimination. In the stratified analysis by sociodemographic and job-related factors, all the interactions did not reach statistical significance (p for interaction > 0.20). CONCLUSION: Experience of COVID-19-related discrimination was associated with severe psychological distress among HCWs. During the pandemic, effective measures should be taken to prevent the development of negative mental health outcomes in HCWs who experience discrimination.

Exploring the threshold for the start of respiratory syncytial virus infection epidemic season using sentinel surveillance data in Japan.

Introduction: An unusual seasonality of respiratory syncytial virus (RSV) infection in Japan is observed in recent years after 2017, becoming challenging to prepare for: a seasonal shift from autumn-winter to summer-autumn in 2017-2019, no major epidemic in 2020, and an unusually high number of cases reported in 2021. Methods: To early detect the start-timing of epidemic season, we explored the reference threshold for the start-timing of the epidemic period based on the number of cases per sentinel (CPS, a widely used indicator in Japanese surveillance system), using a relative operating characteristic curve analysis (with the epidemic period defined by effective reproduction number). Results: The reference values of Tokyo, Kanagawa, Osaka, and Aichi Prefectures were 0.41, 0.39, 0.42, and 0.24, respectively. Discussion: The reference CPS value could be a valuable indicator for detecting the RSV epidemic and may contribute to the planned introduction of monoclonal antibody against RSV to prevent severe outcomes.

COVID-19-related discrimination, PTSD symptoms, and psychological distress in healthcare workers.

To date, little effort has been made to examine if frontline workers who deal with COVID-19 patients are more likely to experience discrimination than second-line workers. Also, little information has appeared on how COVID-19-related discrimination affects PTSD symptoms in healthcare workers. We aimed to examine the association between COVID-19-related discrimination and frontline worker status. We further aimed to examine how COVID-19-related discrimination was associated with PTSD symptoms and psychological distress. We studied 647 healthcare workers. For the association between COVID-19-related discrimination and frontline worker status, we conducted multivariable logistic regression adjusting for age, sex and living alone. For the association of COVID-19-related discrimination with PTSD symptoms and psychological distress, we performed multivariable regression using hierarchical adjustments for age, sex, living alone, alcohol consumption, exercise and frontline worker status. Bias-corrected and accelerated bootstrap confidence intervals (CIs) were used. A total of 136 individuals worked on the frontline and the largest group were nurses (n = 81, 59.6%). Frontline workers had increased odds of COVID-19-related discrimination compared with second-line workers (odds ratio = 2.60, 95% CI = 1.37-4.96). COVID-19-related discrimination was associated with PTSD symptoms and psychological distress even at the highest level of adjustment (ß = 0.67, 95% CI = 0.10-1.23; ß = 2.43, 95% CI = 0.91-3.95, respectively). Frontline workers are more likely to experience COVID-19-related discrimination than second-line workers. Such discrimination may result in PTSD symptoms and psychological distress. Interventions to prevent COVID-19-related discrimination against healthcare workers, for example anti-discrimination campaigns, are important.

Decrease in overdispersed secondary transmission of COVID-19 over time in Japan.

Coronavirus disease 2019 (COVID-19) has been described as having an overdispersed offspring distribution, i.e. high variation in the number of secondary transmissions of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) per single primary COVID-19 case. Accordingly, countermeasures focused on high-risk settings and contact tracing could efficiently reduce secondary transmissions. However, as variants of concern with elevated transmissibility continue to emerge, controlling COVID-19 with such focused approaches has become difficult. It is vital to quantify temporal variations in the offspring distribution dispersibility. Here, we investigated offspring distributions for periods when the ancestral variant was still dominant (summer, 2020; wave 2) and when Alpha variant (B.1.1.7) was prevailing (spring, 2021; wave 4). The dispersion parameter (k) was estimated by analysing contact tracing data and fitting a negative binomial distribution to empirically observed offspring distributions from Nagano, Japan. The offspring distribution was less dispersed in wave 4 (k = 0.32; 95% confidence interval (CI) 0.24-0.43) than in wave 2 (k = 0.21 (95% CI 0.13-0.36)). A high proportion of household transmission was observed in wave 4, although the proportion of secondary transmissions generating more than five secondary cases did not vary over time. With this decreased variation, the effectiveness of risk group-focused interventions may be diminished.

Increasing seroprevalence but waning herd immunity against measles after elimination: Longitudinal seroepidemiology of measles in Osaka Prefecture, Japan, 2003-2020.

Japan is one of the countries conducting longitudinal serosurveillance of vaccine-preventable diseases. We conducted surveillance of the local measles-specific antibody titer, calculated the effective reproduction number (Re), and compared data of four terms: term 1, 2003-2006 (before the introduction of the second shot of measles-containing vaccine); term 2, 2007-2010 (early term toward measles elimination); term 3, 2011-2014 (later term toward measles elimination); and term 4, 2015-2020 (after elimination of measles in Japan). Approximately 250 sera from volunteers aged 0 to ≥ 40 years were collected and examined for measles-specific IgG using the gelatin particle agglutination (PA) method annually from 2003 to 2020. Seroprevalence and the geometric mean of the PA antibody titer were examined by term. Re was calculated using the age-dependent proportion immune and contact matrix for each term. Of the 4,716 sera, 886 in term 1, 1,217 in term 2, 1,069 in term 3, and 1,544 in term 4 were collected. The seroprevalence gradually increased from term 1 (88.3% CI 86.0-90.3) to term 4 (95.7% CI 94.6-96.7), and the seroprevalence of term 1 was significantly lower than those of other terms (Fisher's exact test, p < 0.001), with PA titer ≥ 16 as positive. By contrast, PA antibody titers significantly decreased from term 1 (median 1,024) to term 4 (median 256) (Mann-Whitney U test, p < 0.001). With the protection level (PA titer ≥ 128 and ≥ 256) as positive, Re gradually increased from term 1 (1.8 and 2.3) to term 4 (2.5 and 4.8, respectively). Waning levels of measles antibodies potentially increase the measles susceptibility in Osaka, Japan. This trend might imply a limitation of vaccine-induced immunity in the absence of a natural booster for wild strains after measles elimination. This study provides a cue for maintaining continuous measles elimination status in the future.

Title: Factors associated with time lag between symptom onset and reporting in the first epidemic wave of COVID-19 in Osaka, Japan.

Objectives: Longer reporting lags after symptom onset reportedly exert a substantial impact on onward transmission, increasing outbreak probability. Our study investigated the risk factors associated with reporting lag. Methods: Using active epidemiological surveillance data for all symptomatic cases reported in Osaka Prefecture during the first wave of the coronavirus disease 2019 (COVID-19) epidemic (February 1-May 13, 2020), multivariable regression analyses were implemented to estimate the effects of exposure variables on reporting lag, by controlling for potential confounders. Results: Cases in their 30s showed a longer reporting lag than cases ≥ 80 years old. Cases who lived in areas with a high COVID-19 incidence demonstrated a longer reporting lag. Cases with a history of visiting a nightlife district also showed longer reporting lag than cases without such a history. Healthcare workers and cases with immunodeficiency both displayed shorter reporting lags than others. Conclusion: Identifying newly infected cases as soon as possible and increased testing capacity for all age groups, and for individuals with a history of visiting high infection-risk areas, represented important measures in shortening reporting lags in the first wave period. The evidence from this study may provide lessons for controlling future emerging diseases.

Phenomenological and mechanistic models for predicting early transmission data of COVID-19.

Forecasting future epidemics helps inform policy decisions regarding interventions. During the early coronavirus disease 2019 epidemic period in January-February 2020, limited information was available, and it was too challenging to build detailed mechanistic models reflecting population behavior. This study compared the performance of phenomenological and mechanistic models for forecasting epidemics. For the former, we employed the Richards model and the approximate solution of the susceptible-infected-recovered (SIR) model. For the latter, we examined the exponential growth (with lockdown) model and SIR model with lockdown. The phenomenological models yielded higher root mean square error (RMSE) values than the mechanistic models. When using the numbers from reported data for February 1 and 5, the Richards model had the highest RMSE, whereas when using the February 9 data, the SIR approximation model was the highest. The exponential model with a lockdown effect had the lowest RMSE, except when using the February 9 data. Once interventions or other factors that influence transmission patterns are identified, they should be additionally taken into account to improve forecasting.

Analysis of the effect of feedback feeding on the farm-level occurrence of porcine epidemic diarrhea in Kagoshima and Miyazaki Prefectures, Japan.

When a large-scale epidemic of porcine epidemic diarrhea (PED) occurred in 2013 in Japan, feedback feeding (feeding feces and gut tissues of infected piglets) was attempted to impart immunity to sows and immunize nursing piglets via breastfeeding. This study evaluated the effect of feedback feeding on PED control at 172 farms in Kagoshima and Miyazaki Prefectures. Univariable and multivariable generalized linear models were used to analyze the associations between conduct of feedback feeding and damage from the outbreak (outbreak period and the number of piglet deaths) at the farm level. The within-farm outbreak period shortened over time after the regional outbreak began on Kyushu Island (P=0.009) and was longer on large-scale farms (mean 66.0 days, P=0.003) than small-scale farms (29.4 days) and on farms that used feedback feeding (145.2 days, P=0.059) than those that did not (66.0 days). The number of dead piglets decreased over time since the first regional case (P<0.001) and was higher at farrow-to-finish farms (3.8 piglets/sow, P<0.001) than reproduction farms (0.7 piglets/sow). The effect of feedback feeding on the number of dead piglets was not significant, but its interaction term with farm style had a significant effect (5.0 more piglet deaths at reproduction farms than fallow-to-finish farms, P=0.001). These results suggest that feedback feeding made the damage from PED worse, though it was well established at a later stage of the regional PED epidemic.

Alleviation of masticatory disturbance with an occlusal splint in a Duchenne muscular dystrophy patient.

AIM: To present an occlusal splint effective for alleviating masticatory disturbance in Duchenne muscular dystrophy (DMD). CASE REPORT: A 13-year-old male DMD patient with masticatory disturbance presented with an open bite, with occlusal contact only between the first and second molars bilaterally and reduced masticatory performance. We applied an occlusal splint that achieved occlusal contact for all teeth and monitored its effects on masticatory function over 6 years. The occlusal splint increased occlusal contact points from 11 to 60. Although occlusal force remained at 13.9-16 kg, masticatory performance increased, and the number of mastication strokes increased from 124 to 169. Masseter muscle activity decreased from 76.8% to 33.4% maximum voluntary contraction (MVC) and digastric muscle activity increased from 8.7% to 18.0% MVC. Time from start of peanut mastication to swallowing decreased, and the vertical mastication cycle diameter and its width on the habitual side increased. CONCLUSIONS: Masticatory disturbance in a DMD patient was alleviated using an occlusal splint. The number of mastication strokes and the digastric to masseter muscle activity ratio were increased. Furthermore, the mastication cycle was enlarged, which increased masticatory movement. As masseter muscle activity during mastication decreased, the occlusal splint likely reduced muscle fatigue during masticatory movement.

Seasonal shift in epidemics of respiratory syncytial virus infection in Japan.

In Japan, respiratory syncytial virus (RSV) infection generally has occurred during autumn and winter. However, a possible change in the seasonal trend of RSV infection has been observed recently. The current study was conducted to determine whether the epidemic season of RSV infection in Japan has indeed changed significantly. We used expectation-based Poisson scan statistics to detect periods with high weekly reported RSV cases (epidemic cluster), and the epidemic clusters were detected between September and December in the 2012-2016 seasons while those were detected between July and October in the 2017-2019 seasons. Non-linear and linear ordinary least squares regression models were built to evaluate whether there is a difference in year trend in the epidemic seasonality, and the epidemic season was shifted to earlier in the year in 2017-2019 compared to that in 2012-2016. Although the reason for the shift is unclear, this information may help in clinical practice and public health.

Time Series Analysis of Climate and Air Pollution Factors Associated with Atmospheric Nitrogen Dioxide Concentration in Japan.

Nitrogen dioxide (NO2) is an air pollutant discharged from combustion of human activities. Nitrous acid (HONO), measured as NO2, is thought to impact respiratory function more than NO2. HONO and NO2 have an equilibrium relationship, and their reaction is affected by climate conditions. This study was conducted to discuss the extent of HONO contained in NO2, depending on the level of urbanization. Whether climate conditions that promote HONO production enhanced the level of NO2 measured was investigated using time series analysis. Climate and outdoor air pollution data measured in April 2009-March 2017 in urban (Tokyo, Osaka, and Aichi) and rural (Yamanashi) areas in Japan were used for the analysis. Air temperature had a trend of negative associations with NO2, which might indicate the decomposition of HONO in the equilibrium between HONO and NO2. The associations of relative humidity with NO2 did not have consistent trends by prefecture: humidity only in Yamanashi was positively associated with NO2. In high relative humidity conditions, the equilibrium goes towards HONO production, which was observed in Yamanashi, suggesting the proportion of HONO in NO2 might be low/high in urban/rural areas.

Containment, Contact Tracing and Asymptomatic Transmission of Novel Coronavirus Disease (COVID-19): A Modelling Study.

When a novel infectious disease emerges, enhanced contact tracing and isolation are implemented to prevent a major epidemic, and indeed, they have been successful for the control of severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS), which have been greatly reduced without causing a global pandemic. Considering that asymptomatic and pre-symptomatic infections are substantial for the novel coronavirus disease (COVID-19), the feasibility of preventing the major epidemic has been questioned. Using a two-type branching process model, the present study assesses the feasibility of containing COVID-19 by computing the probability of a major epidemic. We show that if there is a substantial number of asymptomatic transmissions, cutting chains of transmission by means of contact tracing and case isolation would be very challenging without additional interventions, and in particular, untraced cases contribute to lowering the feasibility of containment. Even if isolation of symptomatic cases is conducted swiftly after symptom onset, only secondary transmissions after the symptom onset can be prevented.

Quantitative Release Assessment of mcr-mediated Colistin-resistant Escherichia Coli from Japanese Pigs.

Colistin is a critically important antibiotic for humans. The Japanese government withdrew colistin growth promoter and shifted therapeutic colistin to a second-choice drug for pigs in 2017. A quantitative release assessment of mcr-mediated colistin-resistant Escherichia coli (E. coli) in Japanese finisher pigs was conducted under the World Organisation for Animal Health (OIE) risk assessment framework. Input data included colistin resistance and mcr-1-5 test results for E. coli isolates in the Japan Veterinary Resistance Monitoring System (JVARM), postal survey results regarding indication disease occurrence and colistin use by swine veterinarians in 2017 and 2018, and colistin resistance and mcr monitoring experiments at four pig farms in 2017-2018. An individual-based model was developed to assess the risk: the proportion of Japanese finisher pigs with mcr-1-5-mediated colistin-resistant E. coli dominant in the gut on an arbitrary day. Before implementing risk management measures, the risk was estimated to be 5.5% (95% CI: 4.2%-10.1%). At 12 months after stopping colistin growth promoter, the proportion of pigs with plasmid-mediated colistin-resistant E. coli declined by 52.5% on the experiment farms (95% CI: 8.7%-80.8%). The probability of therapeutic colistin use at the occurrence of bacterial diarrhea declined from 37.3% (95% CI: 30.3%-42.5%) in 2017 to 31.4% (95% CI: 26.1%-36.9%), and that of edema disease declined from 55.0% (95% CI: 46.0%-63.7%) to 44.4% (95% CI: 36.9%-52.0%). After risk management implementation, the risk was estimated to have declined to 2.3% (95% CI: 1.8%-4.3%; 58.2% reduction). Scenario analyses showed that pen-level colistin treatment effectively reduces the risk from 5.5% to 4.7% (14.5% reduction), an effect similar to stoppage of therapeutic colistin (16.4% reduction to 4.6%).

Reactive bite-related tongue lesions in cognitively impaired epilepsy patients: A report of two cases.

AIM: Tongue bites frequently occur during seizures in epilepsy patients. We report two cases of cognitively impaired Lennox-Gastaut syndrome patients with reactive lesions on the tongues. CASE PRESENTATIONS: Case 1 was a 30-year-old man whose chief complaint was mouth pain. Local finding was a small bean-sized pedunculated mass on the tongue, histopathologically diagnosed as inflammatory fibrous hyperplasia. Case 2 was a 45-year-old man whose chief complaint was bleeding from the mouth. His clinical finding was blood loss anemia. Local finding was a 20-mm-diameter pedunculated mass on the tongue, histopathologically diagnosed as pyogenic granuloma. CONCLUSION: These mass lesions were believed to be reactive, caused by repetitive minor damage involving reparative fibrous tissue response. Therefore, the two cases may have involved reparative responses to mucosal injury incurred by accidental bites during epileptic seizures. Intellectual disability made medical treatment difficult and had allowed the massive lesions to form. It is necessary for cognitively impaired epilepsy patients to undergo regular dental examinations in order to get used to dental checks and to increase the number of intraoral observations in the context of close cooperation between dentists and epilepsy therapists.

Effect of chemical tick control practices on tick infestation and Theileria parva infection in an intensive dairy production region of Uganda.

Chemical tick control is a major means of preventing East Coast fever (ECF), especially in sub-Saharan Africa. However, in southwestern Uganda, improper tick control practices have led to severe acaricide resistance. The objectives of this study were to determine the risk factors associated with tick infestation in dairy cattle and Theileria parva infection, and to generate evidence for the prioritization of effective countermeasures for tick control. A cross-sectional study was conducted in 30 farms in Mbarara District, and information on tick control practices and tick infestation were collected. Tick samples were collected from 13 farms to test tick acaricide efficacy. A total of 420 blood samples from calves to adults of exotic- and cross-breed dairy cattle were collected, and T. parva diagnosis via polymerase chain reaction was performed. All the 13 tick populations tested were resistant to deltamethrin (synthetic pyrethroid). Resistance to single-formulation organophosphate-chlorfenvinphos was 39 % (5/13); co-formulations (chlorpyrifos + cypermethrin), 69 % (9/13); and amitraz (amidine), 85 % (11/13). The overall prevalence of T. parva infection at the individual-level was 45.2 % (190/420, 95 % confidence interval (CI): 40.4-50.1), and that at the farm-level was 83 % (25/30, 95 %CI: 65-94). A good quality cattle crush was a preventive factor for tick infestation (odds ratio (OR): 0.32, 95 %CI: 0.15-0.63, p =  0.001). Well-managed acaricide storage (OR: 0.36, 95 %CI: 0.17-0.76, p =  0.008), and a good quality measuring cylinder for acaricide were preventive factors (OR: 0.32, 95 %CI: 0.11-0.93, p = 0.036) for T. parva infection. The risk factors for T. parva infection were a longer period of acaricide use of the same brand (OR: 1.06, 95 %CI: 1.01-1.10, p = 0.012), and a higher frequency (twice a week) of acaricide use rather than once a week (OR: 11.70, 95 %CI: 1.95-70.13, p = 0.007). These risk factors should be given high intervention priority in order to effectively control ticks and prevent T. parva infections in dairy farms. Teaching proper practices to dairy farmers and to technical staff should be used to overcome the severe challenge of acaricide resistance in Mbarara District.

Prevalence of sub-clinical mastitis and its association with milking practices in an intensive dairy production region of Uganda.

A cross-sectional study was conducted to investigate the risk factors for sub-clinical mastitis (SCM) in Mbarara District, an intensive dairy production region of Uganda where hand-milking is dominant. In 30 farms, herd-level milking practices and SCM prevalence were studied. The SCM prevalences were 68.6% (417/608, 95% confidence interval (CI): 64.9-72.2%) and 39.2% (946/2,411, 37.3-41.2%) at the cow- and quarter-levels, respectively. A preventive factor for SCM was cow calmness at the end of milking (OR: 0.20, 95%CI: 0.05-0.79, P=0.021); a risk factor was rough teat-end (OR: 1.75, 95%CI: 1.14-2.68, P=0.011). Good cow hygiene was negatively associated with environmental mastitis (P=0.002). Appropriate hand-milking practices that avoid teat damage are expected to reduce SCM in Uganda.