Your browser doesn't support javascript.
Show: 20 | 50 | 100
Results 1 - 20 de 7.455
Filter
Add filters

Document Type
Year range
1.
Evid Based Dent ; 21(3): 79, 2020 09.
Article in English | MEDLINE | ID: covidwho-1526068

ABSTRACT

Data sources Medline via PubMed, Scopus, Science Direct, Scielo and Google Scholar were searched without language restriction until 28 May 2020.Study selection Publications on the topic of biosafety measures before, during and after dental practice from observational studies, systematic reviews and literature reviews were included, while letters to the editor, individual opinions and books were excluded.Data extraction and synthesis The authors used a narrative review to describe the findings and grouped them into two categories: those considerations before dental care and those during dental consultation.Results The review was based on 43 publications. Of those, 23 were recent reviews, guidelines, protocols and recommendations from national and international organisations; three were COVID-related original studies and the remainder were pre-COVID publications on handpieces, surface contamination, ventilation, aerosols and airborne spread, ultrasonics, hand washing and dental pain management.Conclusions Patients should conform to COVID-19 screening protocols in order to receive dental care and follow all the procedures in place to prevent transmission while in the dental office.


Subject(s)
Betacoronavirus , Coronavirus Infections , Dental Care , Infection Control , Pandemics , Pneumonia, Viral , COVID-19 , Coronavirus Infections/prevention & control , Coronavirus Infections/transmission , Humans , Infection Control/methods , Pneumonia, Viral/prevention & control , Pneumonia, Viral/transmission , SARS-CoV-2
3.
Proc Natl Acad Sci U S A ; 118(43)2021 10 26.
Article in English | MEDLINE | ID: covidwho-1481965

ABSTRACT

Self-amplifying RNA replicons are promising platforms for vaccine generation. Their defects in one or more essential functions for viral replication, particle assembly, or dissemination make them highly safe as vaccines. We previously showed that the deletion of the envelope (E) gene from the Middle East respiratory syndrome coronavirus (MERS-CoV) produces a replication-competent propagation-defective RNA replicon (MERS-CoV-ΔE). Evaluation of this replicon in mice expressing human dipeptidyl peptidase 4, the virus receptor, showed that the single deletion of the E gene generated an attenuated mutant. The combined deletion of the E gene with accessory open reading frames (ORFs) 3, 4a, 4b, and 5 resulted in a highly attenuated propagation-defective RNA replicon (MERS-CoV-Δ[3,4a,4b,5,E]). This RNA replicon induced sterilizing immunity in mice after challenge with a lethal dose of a virulent MERS-CoV, as no histopathological damage or infectious virus was detected in the lungs of challenged mice. The four mutants lacking the E gene were genetically stable, did not recombine with the E gene provided in trans during their passage in cell culture, and showed a propagation-defective phenotype in vivo. In addition, immunization with MERS-CoV-Δ[3,4a,4b,5,E] induced significant levels of neutralizing antibodies, indicating that MERS-CoV RNA replicons are highly safe and promising vaccine candidates.


Subject(s)
Coronavirus Infections/prevention & control , Middle East Respiratory Syndrome Coronavirus/genetics , Middle East Respiratory Syndrome Coronavirus/immunology , RNA, Viral/administration & dosage , Replicon , Viral Vaccines/administration & dosage , Animals , Antibodies, Neutralizing/biosynthesis , Antibodies, Viral/biosynthesis , Coronavirus Infections/genetics , Coronavirus Infections/immunology , Coronavirus Infections/virology , Defective Viruses/genetics , Defective Viruses/immunology , Female , Gene Deletion , Genes, env , Humans , Mice , Mice, Inbred C57BL , Mice, Transgenic , Middle East Respiratory Syndrome Coronavirus/pathogenicity , RNA, Viral/genetics , RNA, Viral/immunology , Vaccines, Virus-Like Particle/administration & dosage , Vaccines, Virus-Like Particle/genetics , Vaccines, Virus-Like Particle/immunology , Viral Vaccines/genetics , Viral Vaccines/immunology , Virulence/genetics , Virulence/immunology
7.
Cell Rep ; 37(5): 109929, 2021 11 02.
Article in English | MEDLINE | ID: covidwho-1466097

ABSTRACT

Current coronavirus (CoV) vaccines primarily target immunodominant epitopes in the S1 subunit, which are poorly conserved and susceptible to escape mutations, thus threatening vaccine efficacy. Here, we use structure-guided protein engineering to remove the S1 subunit from the Middle East respiratory syndrome (MERS)-CoV spike (S) glycoprotein and develop stabilized stem (SS) antigens. Vaccination with MERS SS elicits cross-reactive ß-CoV antibody responses and protects mice against lethal MERS-CoV challenge. High-throughput screening of antibody-secreting cells from MERS SS-immunized mice led to the discovery of a panel of cross-reactive monoclonal antibodies. Among them, antibody IgG22 binds with high affinity to both MERS-CoV and severe acute respiratory syndrome (SARS)-CoV-2 S proteins, and a combination of electron microscopy and crystal structures localizes the epitope to a conserved coiled-coil region in the S2 subunit. Passive transfer of IgG22 protects mice against both MERS-CoV and SARS-CoV-2 challenge. Collectively, these results provide a proof of principle for cross-reactive CoV antibodies and inform the development of pan-CoV vaccines and therapeutic antibodies.


Subject(s)
Antibodies, Viral/immunology , Middle East Respiratory Syndrome Coronavirus/immunology , Spike Glycoprotein, Coronavirus/immunology , Animals , Cell Line , Coronavirus Infections/immunology , Coronavirus Infections/prevention & control , Cross Reactions , Drug Design , Epitope Mapping , Female , Immunoglobulin G/immunology , Male , Mice , Mice, Inbred BALB C , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/chemistry , Viral Vaccines/immunology
10.
Hong Kong Med J ; 26(3): 176-183, 2020 06.
Article in English | MEDLINE | ID: covidwho-1468777

ABSTRACT

INTRODUCTION: This study evaluated the preparedness of family doctors during the early phase of the coronavirus disease 2019 (COVID-19) outbreak in Hong Kong. METHODS: All members of the Hong Kong College of Family Physicians were invited to participate in a cross-sectional online survey using a 20-item questionnaire to collect information on practice preparedness for the COVID-19 outbreak through an email followed by a reminder SMS message between 31 January 2020 and 3 February 2020. RESULTS: Of 1589 family doctors invited, 491 (31%) participated in the survey, including 242 (49%) from private sector. In all, 98% surveyed doctors continued to provide clinical services during the survey period, but reduced clinic service demands were observed in 45% private practices and 24% public clinics. Almost all wore masks during consultation and washed hands between or before patient contact. Significantly more private than public doctors (80% vs 26%, P<0.001) experienced difficulties in stocking personal protective equipment (PPE); more public doctors used guidelines to manage suspected patients. The main concern of the respondents was PPE shortage. Respondents appealed for effective public health interventions including border control, quarantine measures, designated clinic setup, and public education. CONCLUSION: Family doctors from public and private sectors demonstrated preparedness to serve the community from the early phase of the COVID-19 outbreak with heightened infection control measures and use of guidelines. However, there is a need for support from local health authorities to secure PPE supply and institute public health interventions.


Subject(s)
Coronavirus Infections/epidemiology , Coronavirus Infections/prevention & control , Disease Outbreaks/prevention & control , Family Practice/organization & administration , Health Care Surveys/methods , Pandemics/prevention & control , Pneumonia, Viral/epidemiology , Pneumonia, Viral/prevention & control , Surveys and Questionnaires , COVID-19 , COVID-19 Testing , Clinical Laboratory Techniques/methods , Clinical Laboratory Techniques/statistics & numerical data , Communicable Disease Control/methods , Coronavirus Infections/diagnosis , Disease Outbreaks/statistics & numerical data , Female , Hong Kong/epidemiology , Humans , Male , Outcome Assessment, Health Care , Physicians, Family/statistics & numerical data
18.
Sci Rep ; 11(1): 19930, 2021 10 07.
Article in English | MEDLINE | ID: covidwho-1462026

ABSTRACT

Transmission of SARS-CoV-2 by aerosols has played a significant role in the rapid spread of COVID-19 across the globe. Indoor environments with inadequate ventilation pose a serious infection risk. Whilst vaccines suppress transmission, they are not 100% effective and the risk from variants and new viruses always remains. Consequently, many efforts have focused on ways to disinfect air. One such method involves use of minimally hazardous 222 nm far-UVC light. Whilst a small number of controlled experimental studies have been conducted, determining the efficacy of this approach is difficult because chamber or room geometry, and the air flow within them, influences both far-UVC illumination and aerosol dwell times. Fortunately, computational multiphysics modelling allows the inadequacy of dose-averaged assessment of viral inactivation to be overcome in these complex situations. This article presents the first validation of the WYVERN radiation-CFD code for far-UVC air-disinfection against survival fraction measurements, and the first measurement-informed modelling approach to estimating far-UVC susceptibility of viruses in air. As well as demonstrating the reliability of the code, at circa 70% higher, our findings indicate that aerosolized human coronaviruses are significantly more susceptible to far-UVC than previously thought.


Subject(s)
Coronavirus 229E, Human/radiation effects , Coronavirus Infections/prevention & control , Coronavirus OC43, Human/radiation effects , Disinfection/methods , Ultraviolet Rays , Virus Inactivation/radiation effects , Aerosols/isolation & purification , Air Microbiology , COVID-19/prevention & control , Computer Simulation , Coronavirus 229E, Human/isolation & purification , Coronavirus 229E, Human/physiology , Coronavirus OC43, Human/isolation & purification , Coronavirus OC43, Human/physiology , Disinfection/instrumentation , Equipment Design , Humans , Models, Biological
19.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 32(1): 7-9, 2020 Feb 27.
Article in Chinese | MEDLINE | ID: covidwho-1456574

ABSTRACT

Since the end of 2019, the coronavirus disease 2019 (COVID-19) has been extensively epidemic in China, which not only seriously threatens the safety and health of Chinese people, but also challenges the management of other infectious diseases. Currently, there are still approximately three thousand malaria cases imported into China every year. If the diagnosis and treatment of malaria cases as well as the investigation and response of the epidemic foci are not carried out timely, it may endanger patients'lives and cause the possible of secondary transmission, which threatens the achievements of malaria elimination in China. Due to the extensive spread and high transmission ability of the COVID-19, there is a possibility of virus infections among malaria cases during the medical care-seeking behaviors and among healthcare professionals during clinical diagnosis and treatment, sample collection and testing and epidemiological surveys. This paper analyzes the challenges of the COVID-19 for Chinese malaria elimination programme, and proposes the countermeasures in response to the COVID-19 outbreak, so as to provide the reference for healthcare professionals.


Subject(s)
Coronavirus Infections/epidemiology , Disease Outbreaks , Malaria , Pneumonia, Viral/epidemiology , Betacoronavirus , COVID-19 , China , Coronavirus Infections/prevention & control , Humans , Malaria/epidemiology , Malaria/prevention & control , Malaria/transmission , National Health Programs , Pneumonia, Viral/prevention & control , SARS-CoV-2
20.
Bull World Health Organ ; 98(9): 588-589, 2020 Sep 01.
Article in English | MEDLINE | ID: covidwho-1456247

ABSTRACT

Melanie Saville talks to Gary Humphreys about the specific challenges faced in developing and distributing SARS-CoV-2 vaccines and the need to fund end-to-end approaches to support those aims.


Subject(s)
Coronavirus Infections/prevention & control , Drug Development , Pandemics/prevention & control , Pneumonia, Viral/prevention & control , Viral Vaccines , Betacoronavirus , COVID-19 , COVID-19 Vaccines , Clinical Trials as Topic , Humans , SARS-CoV-2
SELECTION OF CITATIONS
SEARCH DETAIL
...