The SARS-CoV-2 Omicron (B.1.1.529) variant exhibits altered pathogenicity, transmissibility, and fitness in the golden Syrian hamster model

The newly emerging SARS-CoV-2 Omicron (B.1.1.529) variant first identified in South Africa in November 2021 is characterized by an unusual number of amino acid mutations in its spike that renders existing vaccines and therapeutic monoclonal antibodies dramatically less effective. The in vivo pathogenicity, transmissibility, and fitness of this new Variant of Concerns are unknown. We investigated these virological attributes of the Omicron variant in comparison with those of the currently dominant Delta (B.1.617.2) variant in the golden Syrian hamster COVID-19 model. Omicron-infected hamsters developed significantly less body weight losses, clinical scores, respiratory tract viral burdens, cytokine/chemokine dysregulation, and tissue damages than Delta-infected hamsters. The Omicron and Delta variant were both highly transmissible (100% vs 100%) via contact transmission. Importantly, the Omicron variant consistently demonstrated about 10-20% higher transmissibility than the already-highly transmissible Delta variant in repeated non-contact transmission studies (overall: 30/36 vs 24/36, 83.3% vs 66.7%). The Delta variant displayed higher fitness advantage than the Omicron variant without selection pressure in both in vitro and in vivo competition models. However, this scenario drastically changed once immune selection pressure with neutralizing antibodies active against the Delta variant but poorly active against the Omicron variant were introduced, with the Omicron variant significantly outcompeting the Delta variant. Taken together, our findings demonstrated that while the Omicron variant is less pathogenic than the Delta variant, it is highly transmissible and can outcompete the Delta variant under immune selection pressure. Next-generation vaccines and antivirals effective against this new VOC are urgently needed.

Incidence of common infectious diseases in Japan during the COVID-19 pandemic

Recent reports indicate that respiratory infectious diseases were suppressed during the novel coronavirus disease-2019 (COVID-19) pandemic. COVID-19 led to behavioral changes aimed to control droplet transmission or contact transmission. In this study, we examined the incidence of common infectious diseases in Japan during the COVID-19 pandemic. COVID-19 data were extracted from the national data based on the National Epidemiological Surveillance of Infectious Diseases (NESID). Common infectious diseases were selected from notifiable infectious diseases under the NESID. The epidemic activity of the diseases during 2015–2020 was evaluated based on the Infectious Disease Weekly Reports published by the National Institute of Infectious Diseases. Each disease was then categorized according to the route of transmission. Many Japanese people had adopted hygienic activities, such as wearing masks and hand washing, even before the COVID-19 pandemic. We examined the correlation between the time-series of disease counts of common infectious diseases and COVID-19 over time using cross-correlation analysis. The weekly number of cases of measles, rotavirus, and several infections transmitted by droplet spread, was negatively correlated with the weekly number of cases of COVID-19 for up to 20 weeks in the past. According to the difference-in-differences analysis, the activity of influenza and rubella was significantly lower starting from the second week in 2020 than that in 2015–2019. Only legionellosis was more frequent throughout the year than in 2015–2019. Lower activity was also observed in some contact transmitted, airborne-transmitted, and fecal-oral transmitted diseases. However, carbapenem-resistant Enterobacteriaceae, exanthema subitum, showed the same trend as that over the previous 5 years. In conclusion, our study shows that public health interventions for the COVID-19 pandemic may have effectively prevented the transmission of most droplet-transmitted diseases and those transmitted through other routes.

Gemini-Mediated Self-Disinfecting Surfaces to Address Contact Transmission of Infectious Diseases

According to both the Center for Disease Control (CDC) and the World Health Organization (WHO), contact-transmission (contact between host tissues and a contaminated surface) is the primary transmission route of infectious diseases worldwide. Usually this is mitigated by adherence to a schedule of repeated regular sanitization, yet this approach is inherently limited by sanitization frequency; conventional disinfectants/methods are only germicidal during the period of application, and surfaces are easily re-contaminated in the interim between cleanings. One solution to this problem is to use agents/coatings that impart self-disinfecting properties onto the existing surfaces such that they display sustained virucidal/antimicrobial properties against pathogens that settle upon them. Quaternary-ammonium organosilicon compounds are ideal candidates to achieve this; cationic surfactants are safe and well-established surface disinfectants while organosilanes are used broadly to form durable coatings with altered surface properties on many different materials. Despite their potential to circumvent disadvantages of traditional disinfection methods, extant commercially available quaternary-ammonium silanes do not display comparable efficacy to standard surface disinfectants, nor have their respective coatings been demonstrated to meet the Environmental Protection Agency’s guidelines for residual/extended efficacy. Inspired by powerful surface activity of double-headed “gemini” surfactants, here we present gemini-diquaternary (GQ) silanes with robust residual germicidal efficacy on various surfaces by incorporating a second cationic “head” to the structure of an conventional mono-quaternary-ammonium silane. Aqueous solutions of GQs were tested in suspension- and surface-antimicrobial assays against an array of pathogens, including Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). GQ performance was benchmarked against the common disinfectants, ethanol, hydrogen peroxide and hypochlorite, as well as against a common antimicrobial mono-quaternary (MQ) silane. Solutions of GQ silanes were efficacious when used for immediate disinfection, showing comparable activity to common disinfectants (>106 fold reduction in 15 seconds). Additionally GQ solutions were demonstrated to impart durable self-disinfecting properties to a variety of porous and nonporous surfaces, efficacious after repeated cycles of abrasion and repeated contaminations, and with superior coating ability and activity (>108 higher activity) than that of the popular MQ silane. GQ solutions as surface treatments show great promise to overcome the limitations of traditional disinfectants in preventing the spread of infectious diseases.

Influence of COVID-19 on Quality of Life among Nurses Treating COVID-19 in Tamil Nadu

Background: COVID-19 is caused by the novel severe acute respiratory syndrome (SARS- COV- 2). The coronavirus is transmitted by different ways, including contact transmission, direct transmission and aerosol transmission. In health care professions the largest and diverse forces are the nurses. Nurses are important in managing the health emergency management crisis because of their vital link between the health care professionals and the patients. The COVID-19 pandemic has placed health care professionals (HCPs) in high stressful circumstances due to increase in patients. Normal life of nurses would be unprecedented disruption and high risk of exposure. The aim of the study is to investigate the quality of life among nurses treating patients during the COVID-19 pandemic. Materials and Methods: The study setting was an online questionnaire survey among nurses in Tamilnadu. This study was conducted in February 2021. There are 127 participants in this survey. The answers regarding how they feel treating COVID-19 Patients, kind of support, impact and quality of life were collected. The data were analysed statistically using SPSS software. The results and observations were recorded in a pie chart. The chi square test and correlation between genders was done and represented in the bar chart. p<0.05 was statistically significant. Results: More than 50% of the nurses responded that their quality of life was good. 43.31% Females have a good quality of life. 78% of the nurses replied that they have both physical and mental impact treating COVID-19 Patients. The association between the gender and quality of life of nurses was found with the help of chi square test p=0.383 (p >0.05) and hence it was statistically not significant. Conclusion: The present study found that the majority of nurses 54.33% have a good quality of life.The officials in the health care system should improve the nurses' working conditions, strategies and their quality of work life, so that nurses will perform their duties properly.

Contact transmission of SARS-CoV-2 on fomite surfaces: surface survival and risk reduction

There is an unprecedented concern regarding the viral strain SARS-CoV-2 and especially its respiratory disease more commonly known as COVID-19. SARS-CoV-2 virus has the ability to survive on different surfaces for extended periods, ranging from days up to months. The new infectious properties of SARS-CoV-2 vary depending on the properties of fomite surfaces. In this review, we summarize the risk factors involved in the indirect transmission pathways of SARS-CoV-2 strains on fomite surfaces. The main mode of indirect transmission is the contamination of porous and non-porous inanimate surfaces such as textile surfaces that include clothes and most importantly personal protective equipment like personal protective equipment kits, masks, etc. In the second part of the review, we highlight materials and processes that can actively reduce the SARS-CoV-2 surface contamination pattern and the associated transmission routes. The review also focuses on some general methodologies for designing advanced and effective antiviral surfaces by physical and chemical modifications, viral inhibitors, etc.

VAKSINASI MASAL COVID-19 DI PELABUHAN LEMBAR LOMBOK BARAT

ABSTRAKWHO (World Health Organization) secara resmi mendeklarasikan virus corona (Covid-19) sebagai pandemi. Virus Covid-19 menyebabkan gejala seperti demam dan batuk, dan kebanyakan bisa sembuh dalam beberapa minggu. Tapi bagi sebagian orang yang berisiko tinggi (kelompok lanjut usia dan orang dengan masalah kesehatan menahun, seperti penyakit jantung, tekanan darah tinggi, atau diabetes), virus corona dapat menyebabkan masalah kesehatan yang serius. Ada dua jalur utama penularan COVID-19, yakni penularan droplet pernapasan dan penularan kontak dekat. Dalam rangka penanggulangan pandemi COVID-19 tidak hanya dilaksanakan dari sisi penerapan protokol kesehatan, namun juga intervensi dengan vaksinasi sebagai bagian dari upaya pencegahan dan Pengendalian COVID-19. Kegiatan vaksinasi masal ini bertujuan agar dapat terbentuk herd immunity (kekebalan kelompok) dan berkurangnya angka kematian akibat COVID-19 pada masyarakat.Jenis vaksin yang digunakan pada kegiatan vaksinasi masal ini adalah Moderna. Jumlah responden yang mengikuti kegiatan ini sebanyak 1.581 orang. Hasil pengabdian didapatkan bahwa jumlah yang melakukan vaksinasi sebanyak 1.581 orang yang terdiri remaja sebanyak 60 orang dewasa sebanyak 1497 orang dan lansia sebanyak 24 orang, diberikan vaksin sebanyak 1.536 orang, ditunda sebanyak 45 orang. Kata kunci: vaksinasi; covid-19; komunitas. ABSTRACTWHO (World Health Organization) has officially declared the coronavirus (Covid-19) as a pandemic. The Covid-19 virus causes symptoms such as fever and cough, and most recover within a few weeks. But for some people who are at high risk (the elderly and people with chronic health problems, such as heart disease, high blood pressure, or diabetes), the coronavirus can cause serious health problems. There are two main routes of transmission of COVID-19, namely respiratory droplet transmission and close contact transmission. In the context of dealing with the COVID-19 pandemic, it is not only implemented in terms of implementing health protocols but also interventions with vaccinations as part of efforts to prevent and control COVID-19. This mass vaccination activity aims to form herd immunity and reduce the mortality rate due to COVID-19 in the community. The type of vaccine used in this mass vaccination activity is Moderna. The number of respondents who participated in this activity was 1,581 people. The results of the service found that the number of people who registered for Pcare was 1,581 people, consisting of 60 teenagers, 1497 adults, and 24 elderly people, 1,536 people were given the vaccine, 45 people were delayed. Keywords: vaccination; covid-19; community.

Infection of wild-type mice by SARS-CoV-2 B.1.351 variant indicates a possible novel cross-species transmission route

COVID-19 is identified as a zoonotic disease caused by SARS-CoV-2, which also can cross-transmit to many animals but not mice. Genetic modifications of SARS-CoV-2 or mice enable the mice susceptible to viral infection. Although neither is the natural situation, they are currently utilized to establish mouse infection models. Here we report a direct contact transmission of SARS-CoV-2 variant B.1.351 in wild-type mice. The SARS-CoV-2 (B.1.351) replicated efficiently and induced significant pathological changes in lungs and tracheas, accompanied by elevated proinflammatory cytokines in the lungs and sera. Mechanistically, the receptor-binding domain (RBD) of SARS-CoV-2 (B.1.351) spike protein turned to a high binding affinity to mouse angiotensin-converting enzyme 2 (mACE2), allowing the mice highly susceptible to SARS-CoV-2 (B.1.351) infection. Our work suggests that SARS-CoV-2 (B.1.351) expands the host range and therefore increases its transmission route without adapted mutation. As the wild house mice live with human populations quite closely, this possible transmission route could be potentially risky. In addition, because SARS-CoV-2 (B.1.351) is one of the major epidemic strains and the mACE2 in laboratory-used mice is naturally expressed and regulated, the SARS-CoV-2 (B.1.351)/mice could be a much convenient animal model system to study COVID-19 pathogenesis and evaluate antiviral inhibitors and vaccines.

Factors Affecting COVID-19 Transmission and Modelling of Close Contact Tracing Strategies

Background: Close contact tracing is an essential measure that countries are applying to combat the epidemic of COVID-19. The purpose of contact tracing is to rapidly identify potentially infected individuals and prevent further spread of the disease. In this study, based on the factors affecting the COVID-19 transmission, a scoring protocol is provided for close contact tracing. Methods: First, the factors affecting the COVID-19 transmission in close contacts were identified by a rapid review of the literature. Data were gathered by searching the Embase, PubMed, Google Scholar, and Scopus databases. Then, by formulating and scoring the identified factors with two sessions of the expert panel, close contact transmission risk score determined, and a protocol for contacts tracing was designed. Results: Close contact transmission risk depends on the contact environment characteristics, the infectivity (virus shedding) of the sentinel case, and contact characteristics. Based on these factors, the close contact transmission risk score and contact tracing protocol were prepared. Conclusion: The close contact transmission risk scores will provide the ability to contact classifications and developing specific tracing strategies for them. Given that there are not any specific treatments for COVID-19 and lack of universal vaccination, applying nonpharmaceutical measures such as contact tracing along with physical distancing is very crucial. Therefore, we recommended this model to the evaluation of exposure risk and contact tracing.

Consequences of Migrating U.S. Contagious Facilities Into General Hospitals, 1900–1950

Until the 1880s, hospitals excluded contagious disease patients from admission because of the danger they posed to other patients; by the 1950s, contagious disease care had literally moved into the general hospital. This article correlates the changing isolation facility designs with changing disease incidence and prevention strategies. It argues that isolation moved into the hospital in stages that have consequence for isolation facility design today. Between the 1890s and 1940s, contagious disease care shifted from remote isolation hospitals (commonly known as pest houses) to separate contagious disease hospitals, to contagious disease “units” adjacent to or within a general hospital facility, and to isolation rooms included in nursing units. The architectural history of isolation facility designs shows that the integration of isolation facilities into general hospitals relied on the success of new aseptic nursing procedures that prevented contact transmission but which downgraded the need for spatial separation to prevent airborne transmission. In the second half of the 20th century, federal funding and standards made isolation rooms in the hospital the norm. This migration coincided with a historically unprecedented reduction in contagious disease incidence produced by successful vaccines and antibiotics. By the 1980s, the rise of new and antibiotic resistant diseases led to extensive redesigns of the in-house isolation rooms to make them more effective. This article suggests that it is time to rethink isolation not just at the detail level but in terms of its location in relation to the general hospital.