Transmission of SARS-CoV-2 in Domestic Cats Halfmann, Peter J; Hatta, Masato; Chiba, Shiho ...
New England journal of medicine/The New England journal of medicine,
08/2020, Letnik:
383, Številka:
6
Journal Article
At the end of 2019, a novel coronavirus (severe acute respiratory syndrome coronavirus 2; SARS-CoV-2) was detected in Wuhan, China, that spread rapidly around the world, with severe consequences for ...human health and the global economy. Here, we assessed the replicative ability and pathogenesis of SARS-CoV-2 isolates in Syrian hamsters. SARS-CoV-2 isolates replicated efficiently in the lungs of hamsters, causing severe pathological lung lesions following intranasal infection. In addition, microcomputed tomographic imaging revealed severe lung injury that shared characteristics with SARS-CoV-2−infected human lung, including severe, bilateral, peripherally distributed, multilobular ground glass opacity, and regions of lung consolidation. SARS-CoV-2−infected hamsters mounted neutralizing antibody responses and were protected against subsequent rechallenge with SARS-CoV-2. Moreover, passive transfer of convalescent serum to naïve hamsters efficiently suppressed the replication of the virus in the lungs even when the serum was administrated 2 d postinfection of the serum-treated hamsters. Collectively, these findings demonstrate that this Syrian hamster model will be useful for understanding SARS-CoV-2 pathogenesis and testing vaccines and antiviral drugs.
Although infection by SARS-CoV-2, the causative agent of coronavirus pneumonia disease (COVID-19), is spreading rapidly worldwide, no drug has been shown to be sufficiently effective for treating ...COVID-19. We previously found that nafamostat mesylate, an existing drug used for disseminated intravascular coagulation (DIC), effectively blocked Middle East respiratory syndrome coronavirus (MERS-CoV) S protein-mediated cell fusion by targeting transmembrane serine protease 2 (TMPRSS2), and inhibited MERS-CoV infection of human lung epithelium-derived Calu-3 cells. Here we established a quantitative fusion assay dependent on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) S protein, angiotensin I converting enzyme 2 (ACE2) and TMPRSS2, and found that nafamostat mesylate potently inhibited the fusion while camostat mesylate was about 10-fold less active. Furthermore, nafamostat mesylate blocked SARS-CoV-2 infection of Calu-3 cells with an effective concentration (EC)
around 10 nM, which is below its average blood concentration after intravenous administration through continuous infusion. On the other hand, a significantly higher dose (EC
around 30 mM) was required for VeroE6/TMPRSS2 cells, where the TMPRSS2-independent but cathepsin-dependent endosomal infection pathway likely predominates. Together, our study shows that nafamostat mesylate potently inhibits SARS-CoV-2 S protein-mediated fusion in a cell fusion assay system and also inhibits SARS-CoV-2 infection in vitro in a cell-type-dependent manner. These findings, together with accumulated clinical data regarding nafamostat's safety, make it a likely candidate drug to treat COVID-19.
While there are various attempts to administer COVID-19-convalescent plasmas to SARS-CoV-2-infected patients, neither appropriate approach nor clinical utility has been established. We examined the ...presence and temporal changes of the neutralizing activity of IgG fractions from 43 COVID-19-convalescent plasmas using cell-based assays with multiple endpoints. IgG fractions from 27 cases (62.8%) had significant neutralizing activity and moderately to potently inhibited SARS-CoV-2 infection in cell-based assays; however, no detectable neutralizing activity was found in 16 cases (37.2%). Approximately half of the patients (~ 41%), who had significant neutralizing activity, lost the neutralization activity within ~ 1 month. Despite the rapid decline of neutralizing activity in plasmas, good amounts of SARS-CoV-2-S1-binding antibodies were persistently seen. The longer exposure of COVID-19 patients to greater amounts of SARS-CoV-2 elicits potent immune response to SARS-CoV-2, producing greater neutralization activity and SARS-CoV-2-S1-binding antibody amounts. The dilution of highly-neutralizing plasmas with poorly-neutralizing plasmas relatively readily reduced neutralizing activity. The presence of good amounts of SARS-CoV-2-S1-binding antibodies does not serve as a surrogate ensuring the presence of good neutralizing activity. In selecting good COVID-19-convalescent plasmas, quantification of neutralizing activity in each plasma sample before collection and use is required.
Coronavirus disease 2019 (COVID-19) is a novel infectious disease affecting the general population worldwide. A fever and cough are the common clinical presentations of COVID-19. In most of these ...patients, computed tomography (CT) shows bilateral peripheral ground-glass opacities. We herein report a case of hemoptysis and lung bulla in the convalescent phase of COVID-19. Based on the clinical observations, alveolar destruction was likely associated with hemoptysis and bulla formation. Therefore, we suggest the follow-up of COVID-19 patients whose clinical parameters indicate alveolar damage, even after their symptoms improve.
Tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis (Tdap) vaccine is generally used for booster vaccination of infants in Europe and the United States to avoid increased ...reactogenicity after diphtheria and tetanus toxoids and acellular pertussis (DTaP) vaccination. However, Japan has extended the use of additional DTaP vaccination without reducing the antigen dose for diphtheria and pertussis in adolescents and adults, despite limited reports on its safety in adults. This prospective, observational, questionnaire-based study investigated the occurrence of adverse events (AEs) following DTaP vaccination between June 2018 and June 2019 in participants aged 10 years or older. Of the 250 eligible participants, 235 (94%) responded regarding AEs. Among them, 133 (56.6%) reported AEs, of which 39 reported systemic AEs (16.6%) and 120 reported local AEs (51.1%) attributed to DTaP vaccination. The incidence of local AEs was markedly higher with DTaP vaccination than with non-DTaP vaccination (51.1% vs. 10.5%), and AEs appeared later (P < 0.01) and lasted longer (P < 0.01) with DTaP vaccination. However, more than 75% of these AEs resolved within 7 days. DTaP vaccination was not associated with any serious AEs. These results indicate that the DTaP vaccine can be widely used as a booster in adults as an alternative to the Tdap vaccine.
Antimicrobial resistance (AMR) is a major multinational public health concern. The Japanese government set goals in its AMR action plan to reduce use of oral cephalosporins, macrolides, and ...quinolones by half between 2013 and 2020. We aimed to evaluate antimicrobial use in children in Japan by observing prescription patterns as an interim assessment of the national AMR action plan.
Using the national health claims database, we retrospectively analyzed all oral antimicrobials dispensed from outpatient pharmacies in Japan to children under 15 years old from 2013 to 2016 by age, prefecture, type of antimicrobial, and year. Data were presented as days of therapy (DOTs) per 1000 pediatric inhabitants per day (DOTs/PID). The χ2 test for trends was performed to evaluate annual changes in DOTs/PID overall as well as within each stratum.
A total of 721,627,553 oral antimicrobial DOTs were identified during 2013–2016. No statistically significant changes were observed in total antimicrobial use in children (2013: 28.54 DOTs/PID; 2016: 28.70 DOTs/PID; Ptrend = 0.25) and amount of cephalosporins, macrolides, and quinolones prescribed. Prescription rates of all antimicrobials were highest among children 1–5 years old, peaking at 1 year old. Targeted antimicrobials for the AMR action plan showed similar distribution by age.
The amount of antimicrobials prescribed to children in Japan is not decreasing. Overall antimicrobial prescriptions, as well as prescriptions of cephalosporins, macrolides, and quinolones, were most prevalent in children ≤5 years old. Rigorous antimicrobial stewardship interventions targeting infants and younger children are necessary.
Antimicrobial resistance is a major public health concern. In 2016, the Japanese government launched a national action plan aimed at achieving a 33% and 50% reduction in the number of total and oral ...antimicrobial prescriptions (cephalosporins, macrolides, and quinolones) from the 2013 figures by 2020, respectively. The purpose of this study was to investigate the indications for recent antimicrobial prescriptions and to identify the primary targets for intervention to achieve the aims of the government's action plan.
Using the national health claims database, we retrospectively analyzed oral antibiotic prescriptions for Japanese children aged ≦ 15 years from 2013 to 2016. The trends were analyzed based on days of therapy (DOT) per infectious disease-related visit for each antibiotic. For patients whose chief diagnosis was an infectious disease, the number of antimicrobial prescriptions per diagnosis, their proportion, and the details of the type of antimicrobial were investigated.
In total, 297,197,328 infectious disease-related visits were identified during 2013–2016. Total antimicrobial prescriptions showed a 3.7% reduction from 1.519 DOT/visitor in 2013 to 1.463 DOT/visitor in 2016 (Ptrend < 0.001). Antimicrobials were prescribed for 31.7% and 36.9% of children with upper and lower respiratory tract infection, accounting for 54.6% and 26.2% of all antimicrobial prescriptions, respectively. Third generation cephalosporins and macrolides comprised the majority of these prescriptions.
Antimicrobials were commonly prescribed for children with respiratory infections. Therefore, promoting appropriate antimicrobial use in this population is required to achieve the 2020 goals set by the action plan.