Simple mathematical model for predicting COVID-19 outbreaks in Japan based on epidemic waves with a cyclical trend.

BACKGROUND: Several models have been used to predict outbreaks during the COVID-19 pandemic, with limited success. We developed a simple mathematical model to accurately predict future epidemic waves. METHODS: We used data from the Ministry of Health, Labour and Welfare of Japan for newly confirmed COVID-19 cases. COVID-19 case data were summarized as weekly data, and epidemic waves were visualized and identified. The periodicity of COVID-19 in each prefecture of Japan was confirmed using time-series analysis and the autocorrelation coefficient, which was used to investigate the longer-term pattern of COVID-19 cases. Outcomes using the autocorrelation coefficient were visualized via a correlogram to capture the periodicity of the data. An algorithm for a simple prediction model of the seventh COVID-19 wave in Japan comprised three steps. Step 1: machine learning techniques were used to depict the regression lines for each epidemic wave, denoting the "rising trend line"; Step 2: an exponential function with good fit was identified from data of rising straight lines up to the sixth wave, and the timing of the rise of the seventh wave and speed of its spread were calculated; Step 3: a logistic function was created using the values calculated in Step 2 as coefficients to predict the seventh wave. The accuracy of the model in predicting the seventh wave was confirmed using data up to the sixth wave. RESULTS: Up to March 31, 2023, the correlation coefficient value was approximately 0.5, indicating significant periodicity. The spread of COVID-19 in Japan was repeated in a cycle of approximately 140 days. Although there was a slight lag in the starting and peak times in our predicted seventh wave compared with the actual epidemic, our developed prediction model had a fairly high degree of accuracy. CONCLUSION: Our newly developed prediction model based on the rising trend line could predict COVID-19 outbreaks up to a few months in advance with high accuracy. The findings of the present study warrant further investigation regarding application to emerging infectious diseases other than COVID-19 in which the epidemic wave has high periodicity.

Adaptations in the role of pharmacists under the conditions of the COVID-19 pandemic: a systematic review and meta-analysis.

BACKGROUND: Community pharmacists actively engage in managing the health of local residents, but the COVID-19 pandemic has necessitated rapid adaptations in practice activities. OBJECTIVES: We sought to identify the specific adaptations in practice and the expanded roles of community pharmacists in response to the COVID-19 pandemic. METHODS: We conducted a systematic review of published studies reporting the tasks of pharmacists in community pharmacies or who were involved in pharmacy practices addressing the pandemic. Two investigators independently searched PubMed (December 2019-January 2022) for eligible articles. We conducted a meta-analysis to measure the frequencies of practical activities by pharmacists in response to COVID-19. RESULTS: We identified 30 eligible studies. Meta-analysis of these studies found that the most commonly reported adaptation in pharmacist practice activities was modifying hygiene behaviors, including regular cleaning and disinfection (81.89%), followed by maintaining social distance from staff and clients (76.37%). Educating clients on COVID-19 was reported by 22 studies (72.54%). Telemedicine and home delivery services were provided to clients by 49.03 and 41.98% of pharmacists, respectively. CONCLUSIONS: The roles of community pharmacists in public health activities have adapted and expanded in response to COVID-19, notably by incorporating public health education activities.

Favipiravir for the treatment of patients with COVID-19: a systematic review and meta-analysis.

BACKGROUND: Favipiravir possesses high utility for treating patients with COVID-19. However, research examining the efficacy and safety of favipiravir for patients with COVID-19 is limited. METHODS: We conducted a systematic review of published studies reporting the efficacy of favipiravir against COVID-19. Two investigators independently searched PubMed, the Cochrane Database of Systematic Reviews, MedRxiv, and ClinicalTrials.gov (inception to September 2020) to identify eligible studies. A meta-analysis was performed to measure viral clearance and clinical improvement as the primary outcomes. RESULTS: Among 11 eligible studies, 5 included a comparator group. Comparing to the comparator group, the favipiravir group exhibited significantly better viral clearance on day 7 after the initiation of treatment (odds ratio [OR] = 2.49, 95% confidence interval [CI] = 1.19-5.22), whereas no difference was noted on day 14 (OR = 2.19, 95% CI = 0.69-6.95). Although clinical improvement was significantly better in the favipiravir group on both days 7 and 14, the improvement was better on day 14 (OR = 3.03, 95% CI = 1.17-7.80) than on day 7 (OR = 1.60, 95% CI = 1.03-2.49). The estimated proportions of patients with viral clearance in the favipiravir arm on days 7 and 14 were 65.42 and 88.9%, respectively, versus 43.42 and 78.79%, respectively, in the comparator group. The estimated proportions of patients with clinical improvement on days 7 and 14 in the favipiravir group were 54.33 and 84.63%, respectively, compared with 34.40 and 65.77%, respectively, in the comparator group. CONCLUSIONS: Favipiravir induces viral clearance by 7 days and contributes to clinical improvement within 14 days. The results indicated that favipiravir has strong possibility for treating COVID-19, especially in patients with mild-to-moderate illness. Additional well-designed studies, including examinations of the dose and duration of treatment, are crucial for reaching definitive conclusions.

Spatiotemporal distribution of COVID-19 during the first 7 months of the epidemic in Vietnam.

BACKGROUND: Understanding the spatiotemporal distribution of emerging infectious diseases is crucial for implementation of control measures. In the first 7 months from the occurrence of COVID-19 pandemic, Vietnam has documented comparatively few cases of COVID-19. Understanding the spatiotemporal distribution of these cases may contribute to development of global countermeasures. METHODS: We assessed the spatiotemporal distribution of COVID-19 from 23 January to 31 July 2020 in Vietnam. Data were collected from reports of the World Health Organization, the Vietnam Ministry of Health, and related websites. Temporal distribution was assessed via the transmission classification (local or quarantined cases). Geographical distribution was assessed via the number of cases in each province along with their timelines. The most likely disease clusters with elevated incidence were assessed via calculation of the relative risk (RR). RESULTS: Among 544 observed cases of COVID-19, the median age was 35 years, 54.8% were men, and 50.9% were diagnosed during quarantine. During the observation period, there were four phases: Phase 1, COVID-19 cases occurred sporadically in January and February 2020; Phase 2, an epidemic wave occurred from the 1st week of March to the middle of April (Wave 1); Phase 3, only quarantining cases were involved; and Phase 4, a second epidemic wave began on July 25th, 2020 (Wave 2). A spatial cluster in Phase 1 was detected in Vinh Phuc Province (RR, 38.052). In Phase 2, primary spatial clusters were identified in the areas of Hanoi and Ha Nam Province (RR, 6.357). In Phase 4, a spatial cluster was detected in Da Nang, a popular coastal tourist destination (RR, 70.401). CONCLUSIONS: Spatial disease clustering of COVID-19 in Vietnam was associated with large cities, tourist destinations, people's mobility, and the occurrence of nosocomial infections. Past experiences with outbreaks of emerging infectious diseases led to quick implementation of governmental countermeasures against COVID-19 and a general acceptance of these measures by the population. The behaviors of the population and the government, as well as the country's age distribution, may have contributed to the low incidence and small number of severe COVID-19 cases.

Neuraminidase Inhibitors and Hospital Length of Stay: A Meta-analysis of Individual Participant Data to Determine Treatment Effectiveness Among Patients Hospitalized With Nonfatal 2009 Pandemic Influenza A(H1N1) Virus Infection.

BACKGROUND: The effect of neuraminidase inhibitor (NAI) treatment on length of stay (LoS) in patients hospitalized with influenza is unclear. METHODS: We conducted a one-stage individual participant data (IPD) meta-analysis exploring the association between NAI treatment and LoS in patients hospitalized with 2009 influenza A(H1N1) virus (A[H1N1]pdm09) infection. Using mixed-effects negative binomial regression and adjusting for the propensity to receive NAI, antibiotic, and corticosteroid treatment, we calculated incidence rate ratios (IRRs) and 95% confidence intervals (CIs). Patients with a LoS of <1 day and those who died while hospitalized were excluded. RESULTS: We analyzed data on 18 309 patients from 70 clinical centers. After adjustment, NAI treatment initiated at hospitalization was associated with a 19% reduction in the LoS among patients with clinically suspected or laboratory-confirmed influenza A(H1N1)pdm09 infection (IRR, 0.81; 95% CI, .78-.85), compared with later or no initiation of NAI treatment. Similar statistically significant associations were seen in all clinical subgroups. NAI treatment (at any time), compared with no NAI treatment, and NAI treatment initiated <2 days after symptom onset, compared with later or no initiation of NAI treatment, showed mixed patterns of association with the LoS. CONCLUSIONS: When patients hospitalized with influenza are treated with NAIs, treatment initiated on admission, regardless of time since symptom onset, is associated with a reduced LoS, compared with later or no initiation of treatment.

Seasonality of newly notified pulmonary tuberculosis in Japan, 2007-2015.

BACKGROUND: The seasonality of pulmonary tuberculosis (TB) incidence may indicate season-specific risk factors that could be controlled if they were better understood. The aims of this study were to elucidate how the incidence of TB changes seasonally and to determine the factors influencing TB incidence, to reduce the TB burden in Japan. METHODS: We assessed the seasonality of newly notified TB cases in Japan using national surveillance data collected between 2007 and 2015. To investigate age and sex differences, seasonal variation was analyzed according to sex for all cases and then by stratified age groups (0-4, 5-14, 15-24, 25-44, 45-64, 65-74, and ≥ 75 years). We used Roger's test to analyze the cyclic monthly trends in seasonal variation of TB incidence. RESULTS: A total of 199,856 newly notified TB cases (male, 62.2%) were reported over the past 9-year period. Among them, 60.6% involved patients aged ≥65 years. Overall, the peak months of TB incidence occurred from April to October, excluding September. In the analysis stratified by age group, a significant seasonal variation in TB cases was observed for age groups ≥15 years, whereas no seasonal variation was observed for age groups ≤14 years. For female patients aged ≥25 years, the peak TB epidemic period was seen from June to December, excluding November. Male patients in the same age groups exhibited declining TB incidence from September to March. CONCLUSIONS: TB incidence exhibits seasonality in Japan for people aged > 15 years and peaks in summer to fall. Monthly trends differ according to age and sex. For age groups ≥25 years, cases in women showed longer peaks from June to December whereas cases in men declined from September to December. These results suggest that the seasonality of TB incidence in Japan might be influenced by health checkups in young adults, reactivation of latent TB infection with aging, and lifestyle habits in older adults. These findings can contribute to establishing the potential determinants of TB seasonality in Japan.

Difficulties in tuberculosis infection control in a general hospital of Vietnam: a knowledge, attitude, and practice survey and screening for latent tuberculosis infection among health professionals.

BACKGROUND: In Vietnam, a country with a high tuberculosis (TB) burden, health professionals in both TB-specialized and non-TB-specialized general hospitals have a high risk of acquiring TB. The aims of the present study were to clarify the difficulties in TB infection control at non-TB specialized hospitals and whether any associated risks of latent TB infection exist among health professionals in Vietnam. METHODS: We conducted a cross-sectional study in a national tertiary and general hospital of Hanoi, Vietnam. Participants were health professionals, including physicians, nurses, and other health professionals. We assessed difficulties in TB infection control by conducting a knowledge, attitude, and practice (KAP) survey. We also collected data on the results of tuberculin skin tests (TSTs) conducted during health check-ups for hospital staff to determine whether health professionals had latent TB infection or TB disease. KAP scores were compared among health professional groups (physicians vs. nurses vs. other health professionals). Factors influencing knowledge scores were evaluated using multiple regression analysis. RESULTS: A total 440 health professionals at the study site participated in the KAP survey, and we collected the results of TSTs from a total of 299 health professionals. We observed a high prevalence of latent TB infection (74.2%), especially among participants in the emergency department. Although participants had high KAP scores, some topics were less understood, such as symptoms and risks of TB, proper use of protective equipment such as N95 respirators, and preventing transmission by patients with confirmed or suspected TB. Factors influencing knowledge scores associated with TB were age, a belief that TB is the most important infectious disease, being a medical professional, having previously attended workshops or seminars, and knowing that Vietnam has a high burden of TB. CONCLUSION: In a non-TB specialized hospital of Vietnam, we observed a risk of TB infection among health professionals and difficulties in properly controlling TB infection. Early awareness regarding patients with suspected TB, to apply proper measures and prevent transmission, and education regarding obtaining updated knowledge through scientific information are crucial to enhancing TB infection control in general hospitals of Vietnam.

Factors influencing hospital admission among patients with autopsy-confirmed dementia.

BACKGROUND: The symptoms of geriatric syndromes and the behavioural and psychological symptoms of dementia (BPSD), in addition to clinical conditions, are associated with hospital admission among dementia patients. However, the principal factors that necessitate hospital admission among dementia patients have not been fully elucidated. METHODS: We retrospectively reviewed the data in the medical and autopsy reports of patients who had been treated at a hospital in Toyohashi, Japan. Each patient had been hospitalized sometime between 2012 and 2016 and underwent a brain autopsy. Dementia and the subtypes of dementia were diagnosed neuropathologically. Information about patients' general backgrounds, clinical conditions at the time of admission, and the geriatric syndrome symptoms and BPSD before admission was collected; comparisons were then made between patients with and without dementia and among those with the different major subtypes of dementia. Then, the factors relating to hospital admission of dementia patients were comprehensively evaluated by using principle component analysis. RESULTS: Of the 128 eligible patients, 100 (78.1%) had dementia. In the comparison of patients with and without dementia, patients without dementia were younger at both admission (P = 0.034) and death (P = 0.003). Among the patients with dementia with Lewy bodies, delusions had a significantly high prevalence (P = 0.014). Principal component analysis identified nine components (disinhibition, irritability/lability, agitation/aggression, anxiety, delusions, sleep/night-time behaviour disorders, hallucinations, aberrant motor behaviour, and speech impairment) as the principal factors related to hospital admission among dementia patients. Thus, BPSD were identified as principal factors. CONCLUSIONS: Compared to other factors, BPSD are more likely to cause dementia patients to be admitted to hospital. The present results indicate that measures should be taken to ameliorate the difficulties associated with caring for patients with BPSD at home.

[Effects of drug treatment on the surviral-time in patients with dementia].

AIM: The effect of polypharmacy on the surviral-time in patients with dementia has never been fully elucidated. METHODS: A retrospective study was conducted in a hospital in Aichi, Japan, by reviewing the medical charts and autopsy reports. Patients were hospitalized and neuropathologically diagnosed with dementia. The data on medication was collected from the prescribed drugs taking right before the admission. Patients were divided into two groups according to the number of prescribed drugs: ≥ 5 drugs (polypharmacy) vs. ≤ 4 drugs (non-polypharmacy). "Drugs to be prescribed with special caution" were defined in accordance with the guidelines for medical treatment and its safety in the elderly (2015). RESULTS: Seventy-six patients were eligible, and 39.5% of patients had polypharmacy. The Kaplan-Meier method showed that the polypharmacy group tended to have a shorter survival-time than the non-polypharmacy group (p=0.067). A Cox proportional hazard model showed that the polypharmacy group tended to have a higher risk for a reduced survival-time than the non-polypharmacy group, and this tendency was more prominent after adjusting for sex and age at admission (adjusted hazard ratio, 1.631; 95% confidence interval, 0.991-2.683; p=0.054). "Drugs to be prescribed with special caution", including hypnotic-sedative drugs, antianxiety drugs, antipsychotics, and benzodiazepines, were not found to be risk factors for a reduced survival-time. CONCLUSIONS: The present study showed that polypharmacy in terminal patients with dementia tended to carry a risk for reducing their remaining lifespan. The results warrant further additional study.

Sensitivity and specificity of QuantiFERON-TB Gold Plus compared with QuantiFERON-TB Gold In-Tube and T-SPOT.TB on active tuberculosis in Japan.

BACKGROUND: The QuantiFERON-TB Gold Plus (QFT-Plus) was introduced in 2015 as a new generation of interferon-gamma release assays (IGRAs) designed to detect Mycobacterium tuberculosis infection (TB). Examination of its diagnostic accuracy is crucial before it is launched in Japan. METHOD: We examined 99 patients with laboratory-confirmed active TB (patients) and 117 healthy volunteers with no risk of TB infection (controls) at a medical center in Tokyo, Japan. Blood samples were collected from both the patients and controls and tested using three types of IGRAs: the QFT-Plus, the QuantiFERON-TB Gold In-Tube (QFT-GIT), and the T-SPOT.TB (T-SPOT). The sensitivity and specificity of each IGRA were examined and compared. RESULTS: The sensitivity of the QFT-Plus was 98.9% (95% confidence interval [CI], 0.934-0.998) and similar to that of the QFT-GIT (97.9%; 95% CI, 0.929-0.998) and T-SPOT (96.9%; 95% CI, 0.914-0.994). The specificity of the QFT-Plus was the same as that of the QFT-GIT and T-SPOT (98.1%; 95% CI, 0.934-0.998). One patient with uncontrolled diabetes mellitus showed negative results on all three IGRAs. CONCLUSIONS: The QFT-Plus showed a high degree of agreement with the QFT-GIT and T-SPOT, with high sensitivity and specificity. Severe diabetes mellitus may influence the results of IGRAs. Larger studies are needed to validate the accuracy of the GFT-Plus and determine whether it can contribute as adjunctive method for the early diagnosis of active TB in Japan.

[The consciousness survey and the effect of educational intervention of Advance Care Planning (ACP) including post-mortem to elderly residents living in old New Town of big city].

AIM: Awareness reform aims to enable survival in an aging society, and ultimately, improve healthcare. An ideal way to achieve this is by implementing Advance directive (Ad) and Advance Care Planning (ACP), which do not usually include postmortem events. This study aims to create opportunities for Ad and ACP to include the postmortem period as a trigger for this awareness reform. METHODS: We conducted an Ad/ACP enlightenment lecture, and a questionnaire survey pre- and post-lecture for the elderly in old New Town, which is known for its aging society. The questionnaire comprised 38 multiple-choice questions covering 6 themes assuming an advanced state of dementia. RESULTS: There were 35 participants (7 men and 22 women) aged 40-89 years. Several people left during the lecture, making it difficult to capture the precise transformation effect with regard to changing of mind. However, the effect of enlightenment was identified as a result of the consciousness survey. A statistically significant change in consciousness occurred in response to social contribution after death. Furthermore, notably more people wanted emergency transportation compared to those wanting resuscitation and extension of life. CONCLUSIONS: The medical treatment desired might vary over time. Even the desire for life extension may differ significantly among individuals. This survey indicated a divergent view between the general public and medical staff, regarding a series of medical actions. We must persistently promote opportunities for enlightenment in cooperation with the general public (i.e., the communities and families we serve).

Markers of Disease Severity in Patients with Spanish Influenza in the Japanese Armed Forces, 1919-1920.

We examined preserved medical charts of 470 Spanish influenza patients (8 with fatal cases) hospitalized at former army hospitals in Japan during 1919-1920. The following factors were associated with longer periods of hospitalization: adventitious discontinuous lung sounds, maximum respiration rate, continuation of high fever after hospital admission, and diphasic fever.

Chronological, geographical, and seasonal trends of human cases of avian influenza A (H5N1) in Vietnam, 2003-2014: a spatial analysis.

BACKGROUND: Human cases of highly pathogenic avian influenza A (H5N1) virus infection continue to occur in Southeast Asia. The objective of this study was to identify when and where human H5N1 cases have occurred in Vietnam and how the situation has changed from the beginning of the H5N1 outbreaks in 2003 through 2014, to assist with implementing methods of targeted disease management. METHODS: We assessed the disease clustering and seasonal variation of human H5N1 cases in Vietnam to evaluate the geographical and monthly timing trends. The clustering of H5N1 cases and associated mortality were examined over three time periods: the outbreak period (2003-2005), the post-outbreak (2006-2009), and the recent period (2010-2014) using the flexibly shaped space-time scan statistic. The most likely cases to co-cluster and the elevated risks for incidence and mortality were assessed via calculation of the relative risk (RR). The H5N1 case seasonal variation was analysed as the cyclic trend in incidence data using Roger's statistical test. RESULTS: Between 2003 and 2005, H5N1 cases (RR: 2.15, p = 0.001) and mortality (RR: 2.49, p = 0.021) were significantly clustered in northern Vietnam. After 2010, H5N1 cases tended to occur on the border with Cambodia in the south, while H5N1 mortality clustered significantly in the Mekong delta area (RR: 6.62, p = 0.002). A significant seasonal variation was observed (p < 0.001), with a higher incidence of morbidity in December through April. CONCLUSIONS: These findings indicate that clinical preparedness for H5N1 in Vietnam needs to be strengthened in southern Vietnam in December-April.

Influence of pneumonia complications on the prognosis of patients with autopsy-confirmed Alzheimer's disease, dementia with Lewy bodies, and vascular dementia.

BACKGROUND: Pneumonia is a major, complicated disease in patients with dementia. However, the influence of pneumonia on the prognosis of patients with varying types of dementia has not been fully evaluated. METHODS: We retrospectively analyzed the data from medical and autopsy reports. All study patients had been hospitalized and underwent brain autopsy in a hospital in Toyohashi, Japan, between 2005 and 2014. The patients with subtypes of dementia, specifically Alzheimer's disease (AD), dementia with Lewy bodies (DLB), or vascular dementia (VaD), were neuropathologically diagnosed and examined. Pneumonia incidence, cause of death, and the clinical time-course of dementia were compared among the dementia subtypes. The time to death from dementia onset (survival time) was compared by the Kaplan-Meier method among subtypes of dementia with or without pneumonia. Risk factors for survival time on all study patients were analyzed with the Cox proportional hazard model. RESULTS: Of the 157 eligible patients, 63 (40.1%) had AD, 42 (26.8%) had DLB, and 52 (33.1%) had VaD. Pneumonia complication was observed with high incidence in each subtype of dementia, especially in DLB (90.5%). The median total duration from dementia onset to death was 8 years in AD and DLB, and 5 years in VaD. The VaD subtype had more male patients than AD or DLB (P = 0.010), and age of death in this group was the youngest among the three groups (P = 0.018). A significant difference was observed in the survival time by the Kaplan-Meier method among the three groups (P < 0.001) and among the groups with pneumonia (P = 0.002). The factors associated with shorter survival time were male gender, pneumonia complications, diabetes mellitus, age of dementia onset ≥ 75 years, and VaD. CONCLUSIONS: Pneumonia complications shortened the survival time of patients with AD, DLB, and VaD.

Impact of Bystander Cardiopulmonary Resuscitation on Out-of-Hospital Cardiac Arrest Outcome in Vietnam.

Introduction: Patients experiencing an out-of-hospital cardiac arrest (OHCA) frequently do not receive bystander cardiopulmonary resuscitation (CPR), especially in low- and middle-income countries (LMIC). In this study we sought to determine the prevalence of OHCA patients in Vietnam who received bystander CPR and its effects on survival outcomes. Methods: We performed a multicenter, retrospective observational study of patients (≥18 years) presenting with OHCA at three major hospitals in an LMIC from February 2014-December 2018. We collected data on the hospital and patient characteristics, the cardiac arrest events, the emergency medical services (EMS) system, the therapy methods, and the outcomes and compared these data, before and after pairwise 1:1 propensity score matching, between patients who received bystander CPR and those who did not. Upon admission, we assessed factors associated with good neurological survival at hospital discharge in univariable and multivariable logistic models. Results: Of 521 patients, 388 (74.5%) were men, and the mean age was 56.7 years (SD 17.3). Although most cardiac arrests (68.7%, 358/521) occurred at home and 78.8% (410/520) were witnessed, a low proportion (22.1%, 115/521) of these patients received bystander CPR. Only half of the patients were brought by EMS (8.1%, 42/521) or private ambulance (42.8%, 223/521), 50.8% (133/262) of whom had resuscitation attempts. Before matching, there was a significant difference in good neurological survival between patients who received bystander CPR (12.2%, 14/115) and patients who did not (4.7%, 19/406; P < .001). After matching, good neurological survival was absent in all OHCA patients who did not receive CPR from a bystander. The multivariable analysis showed that bystander CPR (adjusted odds ratio: 3.624; 95% confidence interval 1.629-8.063) was an independent predictor of good neurological survival. Conclusion: In our study, only 22.1% of total OHCA patients received bystander CPR, which contributed significantly to a low rate of good neurological survival in Vietnam. To improve the chances of survival with good neurological functions of OHCA patients, more people should be trained to perform bystander CPR and teach others as well. A standard program for emergency first-aid training is necessary for this purpose.

Aetiological agents of adult community-acquired pneumonia in Japan: systematic review and meta-analysis of published data.

OBJECTIVE: Epidemiological information is essential in providing appropriate empiric antimicrobial therapy for pneumonia. This study aimed to clarify the epidemiology of community-acquired pneumonia (CAP) by conducting a systematic review of published studies in Japan. DESIGN: Systematic review. DATA SOURCE: PubMed and Ichushi web database (January 1970 to October 2022). ELIGIBILITY CRITERIA: Clinical studies describing pathogenic micro-organisms in CAP written in English or Japanese, excluding studies on pneumonia other than adult CAP, investigations limited to specific pathogens and case reports. DATA EXTRACTION AND SYNTHESIS: Patient setting (inpatient vs outpatient), number of patients, concordance with the CAP guidelines, diagnostic criteria and methods for diagnosing pneumonia pathogens as well as the numbers of each isolate. A meta-analysis of various situations was performed to measure the frequency of each aetiological agent. RESULTS: Fifty-six studies were included and 17 095 cases of CAP were identified. Pathogens were undetectable in 44.1% (95% CI 39.7% to 48.5%). Streptococcus pneumoniae was the most common cause of CAP requiring hospitalisation or outpatient care (20.0% (95% CI 17.2% to 22.8%)), followed by Haemophilus influenzae (10.8% (95% CI 7.3% to 14.3%)) and Mycoplasma pneumoniae (7.5% (95% CI 4.6% to 10.4%)). However, when limited to CAP requiring hospitalisation, Staphylococcus aureus was the third most common at 4.9% (95% CI 3.9% to 5.8%). Pseudomonas aeruginosa was more frequent in hospitalised cases, while atypical pathogens were less common. Methicillin-resistant S. aureus accounted for 40.7% (95% CI 29.0% to 52.4%) of S. aureus cases. In studies that used PCR testing for pan-respiratory viral pathogens, human enterovirus/human rhinovirus (9.4% (95% CI 0% to 20.5%)) and several other respiratory pathogenic viruses were detected. The epidemiology varied depending on the methodology and situation. CONCLUSION: The epidemiology of CAP varies depending on the situation, such as in the hospital versus outpatient setting. Viruses are more frequently detected by exhaustive genetic searches, resulting in a significant variation in epidemiology.

Clinical characteristics and mortality risk among critically ill patients with COVID-19 owing to the B.1.617.2 (Delta) variant in Vietnam: A retrospective observational study.

BACKGROUND: SARS-CoV-2 Delta variant caused a large number of COVID-19 cases in many countries, including Vietnam. Understanding mortality risk factors is crucial for the clinical management of severe COVID-19. METHODS: We conducted a retrospective study at an intensive care center in Ho Chi Minh City that urgently built by Bach Mai Hospital during the COVID-19 outbreak in Vietnam, when the Delta variant predominated. Participants were laboratory-confirmed patients with SARS-CoV-2 infection, admitted in August 2021. Data on patients' demographic and clinical characteristics, radiographic and laboratory findings, treatment, and clinical time course were compared between survivors and non-survivors. Risk factors to mortality were assessed using logistic regression. RESULTS: Among 504 eligible COVID-19 patients, case fatality was 52.2%. Unvaccinated patients accounted for 61.2% of non-survivors and 43.6% of survivors (p < 0.001). The time from onset to hospital admission was 8 days in non-survivors and 7 days in survivors (p = 0.004). Among non-survivors, 90.2% developed acute respiratory distress syndrome (ARDS). Oxygen therapy was administered for all patients, but antiviral agent was given to 51.7% of non-survivors. 54.2% of non-survivors tested positive for the bacterial infection using blood culture. The risk factors for mortality were diabetes mellitus, respiration rate, oxygen saturation, vaccination status, time from onset to admission, and older age. CONCLUSIONS: Critical patients with COVID-19 owing to the Delta variant in Vietnam had delayed hospital admission, leading to ARDS and death. Early availability of vaccines and preventing bacterial infections are crucial for reducing mortality of COVID-19, especially in low- and middle-income countries.

Impact of human mobility and networking on spread of COVID-19 at the time of the 1st and 2nd epidemic waves in Japan: An effective distance approach.

BACKGROUND: The influence of human mobility to the domestic spread of COVID-19 in Japan using the approach of effective distance has not yet been assessed. METHODS: We calculated the effective distance between prefectures using the data on laboratory-confirmed cases of COVID-19 from January 16 to August 23, 2020, that were times in the 1st and the 2nd epidemic waves in Japan. We also used the aggregated data on passenger volume by transportation mode for the 47 prefectures, as well as those in the private railway, bus, ship, and aviation categories. The starting location (prefecture) was defined as Kanagawa and as Tokyo for the 1st and the 2nd waves, respectively. The accuracy of the spread models was evaluated using the correlation between time of arrival and effective distance, calculated according to the different starting locations. RESULTS: The number of cases in the analysis was 16,226 and 50,539 in the 1st and 2nd epidemic waves, respectively. The relationship between arrival time and geographical distance shows that the coefficient of determination was R2 = 0.0523 if geographical distance Dgeo and time of arrival Ta set to zero at Kanagawa and was R2 = 0.0109 if Dgeo and Ta set to zero at Tokyo. The relationship between arrival time and effective distance shows that the coefficient of determination was R2 = 0.3227 if effective distance Deff and Ta set to zero at Kanagawa and was R2 = 0.415 if Deff and time of arrival Ta set to zero at Tokyo. In other words, the effective distance taking into account the mobility network shows the spatiotemporal characteristics of the spread of infection better than geographical distance. The correlation of arrival time to effective distance showed the possibility of spreading from multiple areas in the 1st epidemic wave. On the other hand, the correlation of arrival time to effective distance showed the possibility of spreading from a specific area in the 2nd epidemic wave. CONCLUSIONS: The spread of COVID-19 in Japan was affected by the mobility network and the 2nd epidemic wave is more affected than those of the 1st epidemic. The effective distance approach has the impact to estimate the domestic spreading COVID-19.

Knowledge, Attitudes, and Practices Survey among Nursing Care Workers Involved in Caring for Older Adults during the Early Stage of the COVID-19 Pandemic in Japan.

BACKGROUND: As Japan undergoes population aging, nursing care workers play an important role in supporting older adults in the community, which has been particularly critical during COVID-19 pandemic. However, the knowledge, attitudes, and practices (KAP) among nursing care workers regarding COVID-19 have not been fully elucidated. METHODS: A self-administered questionnaire survey was conducted in June 2020 among 481 nursing care workers in the nursing care facilities in Aichi, Japan. We assessed COVID-19-related KAP scores of nursing care workers, and compared them by age, sex, and years of experience. RESULTS: A total of 481 nursing care workers responded to the survey. Out of a maximum of 10 points, the mean (standard deviations) knowledge, attitude, and practice scores were 6.86 (1.45), 7.11 (1.42), and 7.40 (1.89), respectively. Comparisons between the KAP scores revealed significantly higher knowledge scores among older workers (p < 0.001) and significantly higher knowledge scores (p = 0.002) and practice scores (p = 0.033) among workers with more than 20 years of working experience. CONCLUSIONS: The findings revealed that older age and a longer duration of experience were associated with higher COVID-19-related knowledge and practice scores. To better support older adults, it is essential to improve the education system for care workers and to provide environments for delivering necessary information rapidly.