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1.
Avian Pathol ; 50(4): 295-310, 2021 Aug.
Article in English | MEDLINE | ID: mdl-34126817

ABSTRACT

Infectious bronchitis virus (IBV) was first isolated in Australia in 1962. Ongoing surveillance and characterization of Australian IBVs have shown that they have evolved separately from strains found throughout the rest of the world, resulting in the evolution of a range of unique strains and changes in the dominant wild-type strains, affecting tissue tropism, pathogenicity, antigenicity, and gene arrangement. Between 1961 and 1976 highly nephropathogenic genotype GI-5 and GI-6 strains, causing mortalities of 40% to 100%, predominated, while strains causing mainly respiratory disease, with lower mortality rates, have predominated since then. Since 1988, viruses belonging to two distinct and novel genotypes, GIII and GV, have been detected. The genome organization of the GIII strains has not been seen in any other gammacoronavirus. Mutations that emerged soon after the introduction of vaccination, incursion of strains with a novel lineage from unknown sources, recombination between IBVs from different genetic lineages, and gene translocations and deletions have contributed to an increasingly complex IBV population. These processes and the consequences of this variation for the biology of these viruses provide an insight into the evolution of endemic coronaviruses during their control by vaccination and may provide a better understanding of the potential for evolution of other coronaviruses, including SARS-CoV-2. Furthermore, the continuing capacity of attenuated IBV vaccines developed over 40 years ago to provide protection against viruses in the same genetic lineage provides some assurance that coronavirus vaccines developed to control other coronaviruses may continue to be effective for an extended period.


Subject(s)
Biological Evolution , Chickens , Coronaviridae Infections/veterinary , Infectious bronchitis virus/physiology , Poultry Diseases/virology , Animals , Antigenic Variation , Australia/epidemiology , Coronaviridae Infections/epidemiology , Coronaviridae Infections/prevention & control , Coronaviridae Infections/virology , Evolution, Molecular , Genetic Variation , Infectious bronchitis virus/classification , Infectious bronchitis virus/genetics , Infectious bronchitis virus/immunology , Phenotype , Phylogeny , Poultry Diseases/epidemiology , Poultry Diseases/prevention & control , Viral Vaccines
2.
Nat Rev Immunol ; 20(11): 709-713, 2020 11.
Article in English | MEDLINE | ID: mdl-33024281

ABSTRACT

Immunity is a multifaceted phenomenon. For T cell-mediated memory responses to SARS-CoV-2, it is relevant to consider their impact both on COVID-19 disease severity and on viral spread in a population. Here, we reflect on the immunological and epidemiological aspects and implications of pre-existing cross-reactive immune memory to SARS-CoV-2, which largely originates from previous exposure to circulating common cold coronaviruses. We propose four immunological scenarios for the impact of cross-reactive CD4+ memory T cells on COVID-19 severity and viral transmission. For each scenario, we discuss its implications for the dynamics of herd immunity and on projections of the global impact of SARS-CoV-2 on the human population, and assess its plausibility. In sum, we argue that key potential impacts of cross-reactive T cell memory are already incorporated into epidemiological models based on data of transmission dynamics, particularly with regard to their implications for herd immunity. The implications of immunological processes on other aspects of SARS-CoV-2 epidemiology are worthy of future study.


Subject(s)
Antibodies, Viral/biosynthesis , Betacoronavirus/immunology , Coronaviridae Infections/prevention & control , Coronavirus Infections/prevention & control , Pandemics/prevention & control , Pneumonia, Viral/prevention & control , Viral Vaccines/immunology , Adaptive Immunity/drug effects , Betacoronavirus/drug effects , Betacoronavirus/pathogenicity , CD4-Positive T-Lymphocytes/drug effects , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/virology , COVID-19 , COVID-19 Vaccines , Coronaviridae/drug effects , Coronaviridae/immunology , Coronaviridae Infections/epidemiology , Coronaviridae Infections/immunology , Coronaviridae Infections/virology , Coronavirus Infections/epidemiology , Coronavirus Infections/immunology , Coronavirus Infections/virology , Cross Reactions , Humans , Immunity, Herd/drug effects , Immunologic Memory , Pneumonia, Viral/epidemiology , Pneumonia, Viral/immunology , Pneumonia, Viral/virology , Rhinovirus/drug effects , Rhinovirus/immunology , SARS-CoV-2 , Viral Vaccines/administration & dosage , Viral Vaccines/biosynthesis
3.
Clin Immunol ; 220: 108588, 2020 11.
Article in English | MEDLINE | ID: mdl-32905851

ABSTRACT

Though recent reports link SARS-CoV-2 infections with hyper-inflammatory states in children, most children experience no/mild symptoms, and hospitalization and mortality rates are low in the age group. As symptoms are usually mild and seroconversion occurs at low frequencies, it remains unclear whether children significantly contribute to community transmission. Several hypotheses try to explain age-related differences in disease presentation and severity. Possible reasons for milder presentations in children as compared to adults include frequent contact to seasonal coronaviruses, presence of cross-reactive antibodies, and/or co-clearance with other viruses. Increased expression of ACE2 in young people may facilitate virus infection, while limiting inflammation and reducing the risk of severe disease. Further potential factors include recent vaccinations and a more diverse memory T cell repertoire. This manuscript reviews age-related host factors that may protect children from COVID-19 and complications associated, and addresses the confusion around seropositivity and immunity.


Subject(s)
Antibodies, Viral/blood , Betacoronavirus/pathogenicity , Coronaviridae Infections/prevention & control , Coronaviridae/pathogenicity , Coronavirus Infections/prevention & control , Pandemics/prevention & control , Pneumonia, Viral/prevention & control , Adaptive Immunity/drug effects , Adolescent , Asymptomatic Diseases , Betacoronavirus/drug effects , Betacoronavirus/immunology , COVID-19 , Child , Coronaviridae/drug effects , Coronaviridae/immunology , Coronaviridae Infections/epidemiology , Coronaviridae Infections/immunology , Coronaviridae Infections/virology , Coronavirus Infections/epidemiology , Coronavirus Infections/immunology , Coronavirus Infections/virology , Cross Protection , Female , Humans , Immune Evasion/genetics , Immune Evasion/immunology , Immunity, Innate/drug effects , Male , Pneumonia, Viral/epidemiology , Pneumonia, Viral/immunology , Pneumonia, Viral/virology , SARS-CoV-2 , T-Lymphocyte Subsets/immunology , T-Lymphocyte Subsets/virology , United Kingdom/epidemiology , Vaccination , Young Adult
4.
Emerg Microbes Infect ; 9(1): 949-961, 2020 Dec.
Article in English | MEDLINE | ID: mdl-32378471

ABSTRACT

The emergences of coronaviruses have caused a serious global public health problem because their infection in humans caused the severe acute respiratory disease and deaths. The outbreaks of lethal coronaviruses have taken place for three times within recent two decades (SARS-CoV in 2002, MERS-CoV in 2012 and SARS-CoV-2 in 2019). Much more serious than SARS-CoV in 2002, the current SARS-CoV-2 infection has been spreading to more than 213 countries, areas or territories and causing more than two million cases up to date (17 April 2020). Unfortunately, no vaccine and specific anti-coronavirus drugs are available at present time. Current clinical treatment at hand is inadequate to suppress viral replication and inflammation, and reverse organ failure. Intensive research efforts have focused on increasing our understanding of viral biology of SARS-CoV-2, improving antiviral therapy and vaccination strategies. The animal models are important for both the fundamental research and drug discovery of coronavirus. This review aims to summarize the animal models currently available for SARS-CoV and MERS-CoV, and their potential use for the study of SARS-CoV-2. We will discuss the benefits and caveats of these animal models and present critical findings that might guide the fundamental studies and urgent treatment of SARS-CoV-2-caused diseases.


Subject(s)
Betacoronavirus/physiology , Coronaviridae Infections/pathology , Coronaviridae Infections/prevention & control , Coronavirus Infections/pathology , Coronavirus Infections/prevention & control , Disease Models, Animal , Pandemics/prevention & control , Pneumonia, Viral/pathology , Pneumonia, Viral/prevention & control , Research/trends , Animals , COVID-19 , Humans , Middle East Respiratory Syndrome Coronavirus/physiology , SARS Virus/physiology , SARS-CoV-2
6.
Multimedia | Multimedia Resources | ID: multimedia-3768

ABSTRACT

Infografía sobre formas de ayudar a las personas mayores y/o con enfermedades subyacentes durante el COVID-19.


Subject(s)
Betacoronavirus , Coronaviridae Infections/prevention & control , Coronavirus Infections/prevention & control , Aged
7.
Multimedia | Multimedia Resources | ID: multimedia-3769

ABSTRACT

Infografía sobre formas de ayudar a las personas mayores y/o con enfermedades subyacentes que viven con usted.


Subject(s)
Betacoronavirus , Coronaviridae Infections/prevention & control , Coronavirus Infections/prevention & control
9.
Multimedia | Multimedia Resources | ID: multimedia-3521

ABSTRACT

There are simple things we each must do to protect ourselves from #COVID19, including hands washing with soup & water or alcohol-based rub. WHO is launching the #SafeHands Challenge to promote the power of clean hands to fight #coronavirus. Join the challenge & share your hands washing video!


Subject(s)
Hand Disinfection/standards , Pneumonia, Viral/transmission , Betacoronavirus , Hand Disinfection/methods , Coronaviridae Infections/prevention & control
10.
Multimedia | Multimedia Resources | ID: multimedia-3524

ABSTRACT

Wearing a medical mask can help limit the spread of some respiratory diseases. However, using a mask alone is not guaranteed to stop infections. Their use should be combined with other preventive measures. Watch this short video to find out more.


Subject(s)
Betacoronavirus , Pneumonia, Viral/transmission , Pneumonia, Viral/prevention & control , Coronaviridae Infections/prevention & control , Coronaviridae Infections/transmission , Masks/standards
11.
Multimedia | Multimedia Resources | ID: multimedia-3525

ABSTRACT

As with other respiratory illnesses, infections with 2019-nCoV can cause mild symptoms including runny nose, sore throat, cough and fever. It can be more severe for some persons ,and more rarely, it can be fatal. Watch this short video to find out more.


Subject(s)
Betacoronavirus , Pneumonia, Viral/transmission , Coronaviridae Infections/prevention & control , Self Care , Health Promotion
12.
Multimedia | Multimedia Resources | ID: multimedia-3526

ABSTRACT

There are several measures you can adopt to protect yourself against the new coronavirus. Watch this short video and find out what the recommendations from WHO experts are.


Subject(s)
Betacoronavirus , Pneumonia, Viral/transmission , Pneumonia, Viral/prevention & control , Coronaviridae Infections/prevention & control , Self Care , Health Communication
13.
Multimedia | Multimedia Resources | ID: multimedia-3527

ABSTRACT

Learn how health workers are sharing information and caring for patients with the new coronavirus (2019-nCoV) with Dr Janet Diaz, Head of clinical care, Health Emergencies Programme, WHO.


Subject(s)
Betacoronavirus , Pneumonia, Viral/transmission , Pneumonia, Viral/prevention & control , Patient-Centered Care , Coronaviridae Infections/prevention & control , Coronaviridae Infections/transmission
14.
Multimedia | Multimedia Resources | ID: multimedia-3528

ABSTRACT

Recorded version of the live Q&A #askWHO with Dr Rosamund Lewis and WHO's social media manager Aleks Kuzmanovic on the subject of COVID-19 in the workplace. This show was originally broadcast on 27 February 2020, live from WHO Headquarters, Geneva, Switzerland.


Subject(s)
Betacoronavirus , Pneumonia, Viral/transmission , Coronaviridae Infections/prevention & control , Health Communication , Health Promotion , Coronaviridae Infections/transmission , Self Care
15.
Multimedia | Multimedia Resources | ID: multimedia-3529

ABSTRACT

Recorded version of the live Q&A #askWHO with Dr Sylvie Briand, Director, Global Infectious Hazard Preparedness at WHO and Christopher Black, Multimedia Producer in WHO's Communication Department. The show looks at COVID-19 vs flu and was originally broadcast on the 4th of March 2020, live from WHO Headquarters, Geneva, Switzerland.


Subject(s)
Betacoronavirus , Pneumonia, Viral/transmission , Coronaviridae Infections/prevention & control , Health Communication , Health Promotion ,
16.
Multimedia | Multimedia Resources | ID: multimedia-3531

ABSTRACT

COVID-19 is an infectious disease caused by a new coronavirus introduced to humans for the first time. It is spread from person to person mainly through the droplets produced when an infected person speaks, coughs or sneezes. Watch this short animation to learn more about COVID-19 and how to protect yourself against it.


Subject(s)
Betacoronavirus , Pneumonia, Viral/transmission , Self Care , Pneumonia, Viral/prevention & control , Coronaviridae Infections/prevention & control , Health Communication
17.
São Paulo; AMHB;APH; mar. 2020. 62 p.
Monography in Portuguese | LILACS, HomeoIndex Homeopathy, MOSAICO - Integrative health | ID: biblio-1087238

ABSTRACT

Além da reconhecida aplicação nas doenças crônicas, a homeopatia individualizada também pode atuar de forma resolutiva ou complementar nos casos agudos, incluindo as doenças epidêmicas. No entanto, para atingir esse intento, apresenta uma metodologia semiológica e terapêutica específica que deve ser seguida e respeitada, com o risco de não apresentar a eficácia e a segurança desejada. No caso das doenças epidêmicas, que pela virulência dos seus agentes provoca um quadro sintomatológico comum na maioria dos indivíduos suscetíveis, o medicamento homeopático individualizado (medicamento homeopático do gênio epidêmico) deve apresentar semelhança com o conjunto de sinais e sintomas característicos dos pacientes acometidos nos diferentes estágios de cada surto epidêmico. Estudos evidenciam a eficácia e a segurança desta prática profilática e/ou terapêutica em diversas epidemias do passado. Assim sendo, após o levantamento dos possíveis medicamentos homeopáticos individualizados do gênio epidêmico de cada epidemia, sua aplicação profilática e/ou terapêutica em larga escala deve ser sustentada por ensaios clínicos prévios que demonstrem sua eficácia e segurança, em consonância com os aspectos éticos e bioéticos da pesquisa envolvendo seres humanos. Cumprindo essas premissas da boa prática clínica, elaboramos o atual protocolo com o objetivo de investigar, em ensaio clínico randomizado, duplo-cego e placebo-controlado, a eficácia e a segurança de possíveis medicamentos homeopáticos individualizados do gênio epidêmico da COVID-19, em tratamento adjuvante e complementar de pacientes acometidos pela doença. Caso a a eficácia e a segurança se confirme, e tão somente, o(s) medicamento(s) poderão ser utilizado de forma generalizada e coletiva no tratamento e na prevenção da atual epidemia. (AU)


In addition to the recognized application in chronic diseases, individualized homeopathy can also act in a resolutive or complementary way in acute cases, including epidemic diseases. However, to achieve this intent, it presents a specific semiological and therapeutic methodology that must be followed and respected, with the risk of not presenting the desired efficacy and safety. In the case of epidemic diseases, which due to the virulence of their agents causes a common symptomatological picture in most susceptible individuals, the individualized homeopathic medicine (homeopathic medicine of the epidemic genius) should present similarity with the set of characteristic symptoms and signs of the patients affected in the different stages of each epidemic outbreak. Studies show the efficacy and safety of this prophylactic and/or therapeutic practice in several epidemics of the past. Therefore, after the survey of possible homeopathic drugs individualized from the epidemic genius of each epidemic, its prophylactic and/or large-scale therapeutic application should be supported by previous clinical trials that demonstrate its efficacy and safety, in line with the ethical and bioethical aspects of research involving human beings. Fulfilling these premises of good clinical practice, we developed the current protocol with the objective of investigating, in a randomized, double-blind and placebo-controlled clinical trial, the efficacy and safety of possible individualized homeopathic drugs of epidemic genius of COVID-19, in adjuvant and complementary treatment of patients affected by the disease. If efficacy and safety are confirmed, and only in this condition, the medicine may be used in a generalized and collective manner in the treatment and prevention of the current epidemic. (AU)


Subject(s)
Humans , Epidemic Genius , Clinical Protocols , Coronavirus , Coronaviridae Infections/prevention & control , Coronaviridae Infections/therapy , Ethics, Research , SARS Virus , Epidemics , Homeopathy , Brazil/epidemiology
18.
Proc Natl Acad Sci U S A ; 113(11): 3048-53, 2016 Mar 15.
Article in English | MEDLINE | ID: mdl-26976607

ABSTRACT

Outbreaks from zoonotic sources represent a threat to both human disease as well as the global economy. Despite a wealth of metagenomics studies, methods to leverage these datasets to identify future threats are underdeveloped. In this study, we describe an approach that combines existing metagenomics data with reverse genetics to engineer reagents to evaluate emergence and pathogenic potential of circulating zoonotic viruses. Focusing on the severe acute respiratory syndrome (SARS)-like viruses, the results indicate that the WIV1-coronavirus (CoV) cluster has the ability to directly infect and may undergo limited transmission in human populations. However, in vivo attenuation suggests additional adaptation is required for epidemic disease. Importantly, available SARS monoclonal antibodies offered success in limiting viral infection absent from available vaccine approaches. Together, the data highlight the utility of a platform to identify and prioritize prepandemic strains harbored in animal reservoirs and document the threat posed by WIV1-CoV for emergence in human populations.


Subject(s)
Chiroptera/virology , Communicable Diseases, Emerging/virology , Coronaviridae Infections/virology , Coronaviridae/pathogenicity , Angiotensin-Converting Enzyme 2 , Animals , Antibodies, Monoclonal/immunology , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , Cells, Cultured , Chlorocebus aethiops , Coronaviridae/genetics , Coronaviridae/immunology , Coronaviridae/isolation & purification , Coronaviridae/physiology , Coronaviridae Infections/prevention & control , Coronaviridae Infections/transmission , Coronaviridae Infections/veterinary , Cross Reactions , Encephalitis, Viral/virology , Epithelial Cells/virology , Host Specificity , Humans , Lung/cytology , Mice , Mice, Inbred BALB C , Mice, Transgenic , Models, Molecular , Peptidyl-Dipeptidase A/genetics , Peptidyl-Dipeptidase A/physiology , Point Mutation , Protein Conformation , Receptors, Virus/genetics , Receptors, Virus/physiology , Recombinant Fusion Proteins/metabolism , SARS Virus/immunology , Species Specificity , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/physiology , Vero Cells , Virus Replication , Zoonoses
19.
Genet Mol Res ; 14(2): 6340-9, 2015 Jun 11.
Article in English | MEDLINE | ID: mdl-26125838

ABSTRACT

Infectious bronchitis virus (IBV) can multiply effectively in chick embryo kidney (CEK) cells after adapting to the chick embryo. To investigate the dynamic changes in IBV load in the supernatant of primary CEK cells, we developed an SYBR Green I-based real-time polymerase chain reaction assay to quantify nucleic copy numbers of the IBV-Sczy3 strain. The 20, 54, and 87th generations of CEK-adapted IBV-Sczy3 strains were used to infect CEK cells, and then nucleic copy numbers in the samples of supernatant collected at 12, 24, 36, 48, 60, and 72 h were detected. The results showed that the rapid growth period of the virus load of all the 3 generations was approximately 12-36 h post-infection; the peak of the virus load appeared at 36 h post-infection and then decreased gradually in the order of 20th > 54th > 87th for the 3 generations of CEK-adapted strains; the dynamic change curve of the IBV load in the supernatant of primary CEK cells showed a single peak. The results of this study provide a useful reference for CEK-adapted IBV field strains and the production of CEK-attenuated IBV vaccine.


Subject(s)
Coronaviridae Infections/immunology , Infectious bronchitis virus/immunology , Poultry Diseases/immunology , Vaccines, Attenuated/immunology , Viral Vaccines/immunology , Animals , Chick Embryo/immunology , Chick Embryo/virology , Coronaviridae Infections/prevention & control , Coronaviridae Infections/virology , Infectious bronchitis virus/pathogenicity , Kidney/immunology , Kidney/virology , Poultry Diseases/prevention & control , Poultry Diseases/virology , Primary Cell Culture , Vaccines, Attenuated/therapeutic use , Viral Load/immunology , Viral Vaccines/therapeutic use
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