Virulence-Associated Gene Profiles of Escherichia coli Isolated from Chickens with Colibacillosis in Japan and Their Correlation with Pathogenicity in Chicken Embryos.

Colibacillosis, an infectious disease of chickens, is caused by avian pathogenic Escherichia coli (APEC); however, in addition to APEC, other pathogens are also frequently isolated from chickens affected with colibacillosis. Therefore, experimental infections in chickens are necessary to evaluate the pathogenicity of APEC isolates. Recent studies have shown that embryo lethality assays can be used as an alternative method to evaluate the pathogenicity of E. coli. In this study, to determine the important virulence genes associated with the pathogenicity of E. coli, 67 strains of E. coli that possessed different combinations of eight representative virulence genes (cva/cvi, vat, tsh, iucD, papC, irp2, iss, and astA) were isolated from broilers with colibacillosis in Japan, and the chicken embryo lethal assay was conducted. The genes vat, papC, and irp2 showed strong correlation with the level of virulence in E. coli. Our study provides useful information about the important virulence-associated genes in relation to the pathogenicity of E. coli in Japanese chickens.

Nota de investigación- Perfiles de genes asociados a la virulencia de Escherichia coli aislada de pollos con colibacilosis en Japón y su correlación con la patogenicidad en embriones de pollo. La colibacilosis, una enfermedad infecciosa de los pollos, es causada por Escherichia coli patógena aviar (APEC); sin embargo, además de E. coli patógena aviar, también se aíslan con frecuencia otros patógenos de los pollos afectados por colibacilosis. Por lo tanto, las infecciones experimentales en pollos son necesarias para evaluar la patogenicidad de los aislamientos de E. coli patógena aviar. Estudios recientes han demostrado que los ensayos de letalidad embrionaria se pueden utilizar como método alternativo para evaluar la patogenicidad de E. coli. En este estudio, para determinar los genes de virulencia importantes asociados con la patogenicidad de E. coli, 67 cepas de E. coli que poseían diferentes combinaciones de ocho genes de virulencia representativos (cva/cvi, vat, tsh, iucD, papC, irp2, iss, y astA) fueron aisladas de pollos de engorde con colibacilosis en Japón y se llevó a cabo el ensayo de letalidad de embriones de pollo. Los genes vat, papC e irp2 mostraron una fuerte correlación con el nivel de virulencia en E. coli. Este estudio proporciona información útil sobre los genes importantes asociados a la virulencia en relación con la patogenicidad de E. coli en pollos japoneses.

Enhanced event-based surveillance for imported diseases during the Tokyo 2020 Olympic and Paralympic Games.

In 2021, the National Institute of Infectious Diseases, Japan, undertook enhanced event-based surveillance (EBS) for infectious diseases occurring overseas that have potential for importation (excluding coronavirus disease 2019 [COVID-19]) for the Tokyo 2020 Olympic and Paralympic Summer Games (the Games). The pre-existing EBS system was enhanced using the World Health Organization Epidemic Intelligence from Open Sources system and the BlueDot Epidemic Intelligence platform. The enhanced EBS before and during the Games did not detect any major public health event that would warrant action for the Games. However, information from multiple sources helped us identify events, characterize risk and improve confidence in risk assessment. The collaboration also reduced the surveillance workload of the host country, while ensuring the quality of surveillance, even during the COVID-19 pandemic.

Serological survey of influenza A virus infection in Japanese wild boars (Sus scrofa leucomystax).

We conducted a serological survey to detect antibodies against influenza A virus (IAV) in Japanese wild boars in Kagoshima prefecture, Japan, between 2014 and 2017. Seroprevalence against a pandemic-like swine H1N1 (H1N1pdm) virus was identified in 27.1% of specimens, and 1.7% were positive for both swine H1N2 and H3N2 viruses, indicating that wild boars could play an important role in the dynamics of H1N1pdm viral dispersion in the wild. The high frequency of positive results for sera against the H1N1pdm virus suggests that cross-species IAV transmission between wild boars, livestock, and humans is a threat to veterinary and public health.

[Factors related to life expectancy in prefectures: An ecological study using the National Database].

Objective　In recent years, studies have reported a prefectural-level disparity in life expectancy. Therefore, we analyzed the related factors using the National Database (NDB), which includes data pertaining to the specific health checkup conducted for 20 million individuals. By doing so, we aimed to obtain basic data for developing future health promotion measures.Methods　We used specific health checkup items from NDB Open Data for 2014, and life expectancy data from Prefecture Life Table for 2015. The specific health checkup items were adjusted by age using Japanese population data for 2015. A multiple linear regression analysis was conducted using specific health checkup items that were significantly related to average life expectancy as explanatory variables.Results　In men, excessive drinking, smoking, antihypertensive drug use, systolic blood pressure, and hyperglycemia were independently and inversely related to life expectancy. In women, smoking and antihypertensive drug use emerged as significant factors.Conclusions　Analysis using NDB Open Data showed that lifestyle factors such as smoking and drinking, and cardiovascular risk factors such as high blood pressure and hyperglycemia, were strongly related to life expectancy. These result suggest that it is necessary to focus on the above factors when prefectural authorities implement health promotion measures.

Evaluation of the antiviral potential of the soluble forms of glycoprotein D receptors on ocular herpes caused by HSV-1 and HSV-2 infections in a transgenic mouse model.

Ocular herpes, caused by herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) infections, remains an important corneal disease, which may result in loss of vision. Because the frequency of acyclovir resistance in HSV has increased, novel antiviral agents are needed for therapeutic approaches to ocular herpes. Several studies have demonstrated that fusion proteins containing entire ectodomain of HSV glycoprotein D receptors, including herpesvirus entry mediator A (HVEM), nectin-1 and nectin-2, and the Fc portion of human IgG (HVEMIg, nectin-1Ig, and nectin-2Ig, respectively), can exert antiviral effects in vitro and in vivo. Here, to evaluate the antiviral potential of HVEMIg, nectin-1Ig, and nectin-2Ig against ocular infections with HSV, transgenic mice expressing these fusion proteins were ocularly inoculated with HSV-1 and HSV-2. Transgenic mouse lines expressing HVEMIg and nectin-1Ig showed marked resistance to ocular herpes; on the other hand, mouse lines expressing nectin-2Ig did not. Furthermore, to investigate the therapeutic effects of nectin-1Ig, which can neutralize HSVs in vitro against ocular disease, transgenic mouse serum containing nectin-1Ig was dropped into the eyes of wild-type mice after HSV infection. Reduction of severe symptoms could be observed in mice treated with nectin-1Ig serum. These results warrant further study of soluble HVEM and nectin-1 products as preventive and therapeutic agents against ocular herpes caused by HSV-1 and HSV-2 infections, especially nectin-1Ig as a new eye drop.

Evaluation of multinomial logistic regression models for predicting causative pathogens of food poisoning cases.

In cases of food poisoning, it is important for food sanitation inspectors to determine the causative pathogen as early as possible and take necessary measures to minimize outbreaks. Interviews are usually conducted to obtain epidemiological information to aid in the rapid determination of the cause. However, the current method of determining the causative pathogen has the disadvantage of being reliant upon the experience and knowledge of food sanitation inspectors. Here, we analyzed 529 infectious food poisoning incidents reported in five municipalities in the Kinki region to develop a tool for evaluation using a multinomial logistic regression model, which can predict the causative pathogen based on the patients' epidemiological information. This tool predicts the most probable cause of the incident by generating a list of pathogens with the highest probability. As a result of leave-one-out cross validation, the agreement ratio with the actual pathogen was 86.4%, and this ratio increased to 97.5% when the agreement was judged by including the true pathogen within the top three pathogens with the highest probability. In cases where the difference of probability between the first and second candidate pathogen was ≥50%, the agreement ratio increased to 94.2%. Using this tool, it is possible to accurately estimate the causative pathogen at an early stage based on patient information, and this will further help narrow the target of investigations to identify causative agent, thereby leading to a prompt identification, which can prevent the spread of food poisoning.