Influenza – A Model of an Emerging Virus Disease

Intervirology ◽  
1993 ◽  
Vol 35 (1-4) ◽  
pp. 16-25 ◽  
Author(s):  
Robert G. Webster ◽  
Steve M. Wright ◽  
Maria R. Castrucci ◽  
William J. Bean ◽  
Yoshihiro Kawaoka
Keyword(s):  
Influenza A ◽  
Virus Disease ◽  
Emerging Virus

scholarly journals Molecular detection of viral pathogens from suspected viral hemorrhagic fever patients in Ghana

2020 ◽  
pp. 31-35
Author(s):  
Joseph HK Bonney ◽  
Theodore W Asigbee ◽  
Erasmus Kotey ◽  
Keren Attiku ◽  
Franklin Asiedu-Bekoe ◽  
...  
Keyword(s):  
Influenza A ◽  
Virus Disease ◽  
Health Facilities ◽  
African Countries ◽  
Case Definitions ◽  
Viral Pathogens ◽  
Standard Case ◽  
Clinical Specimens ◽  
Influenza A H1n1 ◽  
Case Based

Background: Viral hemorrhagic fevers (VHFs) are infectious illnesses that can cause serious morbidity and mortality to infected persons. During the 2014 Ebola virus disease outbreak in some West African countries, Ghana revamped its surveillance system across the country to prepare, effectively respond and pre-empt any public health concerns Objective: We report on suspected VHF clinical specimens submitted to the Noguchi Memorial Institute for Medical Research (NMIMR) from health facilities across the country for diagnosis within the period under review. This was partly to provide rapid response and to alert the health system to prevent outbreaks and its spread. Methods: From January 2017 to December 2018 clinical specimens of blood from 149 cases of suspected VHFs were collected at health facilities across the country and sent to NMIMR. Patient specimens were tested for viral pathogens including Lassa fever, Yellow fever, Dengue fever, Chikungunya, Zika, Ebola and Marburg by real-time reverse transcription-polymerase chain reaction. A case was however tested for influenza as the patient exhibited respiratory distress symptoms as well. Demographic and clinical information collected on a structured case-based forms were analyzed for each patient. Results: Out of the 149 clinical specimens tested, three (3) were found to be positive, with two (2) being Dengue and one (1) seasonal Influenza A H1N1. Analysis of the case-based forms revealed shortcomings with regards to standard case definitions used to enroll suspected cases. Conclusion: Our results buttress the need for a routine surveillance activity for VHFs to minimize spread and possibly forestall outbreaks. Moreover, febrile illnesses can be caused by a host of pathogens hence there is a need for enhanced diagnosis to help in patient management.

scholarly journals Exacerbation of Influenza A Virus Disease Severity by Respiratory Syncytial Virus Co-Infection in a Mouse Model

Viruses ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1630 ◽  
Author(s):  
Junu A. George ◽  
Shaikha H. AlShamsi ◽  
Maryam H. Alhammadi ◽  
Ahmed R. Alsuwaidi
Keyword(s):  
T Cells ◽  
Respiratory Syncytial Virus ◽  
Influenza A Virus ◽  
Influenza A ◽  
Immune Cell ◽  
Virus Disease ◽  
Viral Loads ◽  
Syncytial Virus

Influenza A virus (IAV) and respiratory syncytial virus (RSV) are leading causes of childhood infections. RSV and influenza are competitive in vitro. In this study, the in vivo effects of RSV and IAV co-infection were investigated. Mice were intranasally inoculated with RSV, with IAV, or with both viruses (RSV+IAV and IAV+RSV) administered sequentially, 24 h apart. On days 3 and 7 post-infection, lung tissues were processed for viral loads and immune cell populations. Lung functions were also evaluated. Mortality was observed only in the IAV+RSV group (50% of mice did not survive beyond 7 days). On day 3, the viral loads in single-infected and co-infected mice were not significantly different. However, on day 7, the IAV titer was much higher in the IAV+RSV group, and the RSV viral load was reduced. CD4 T cells were reduced in all groups on day 7 except in single-infected mice. CD8 T cells were higher in all experimental groups except the RSV-alone group. Increased airway resistance and reduced thoracic compliance were demonstrated in both co-infected groups. This model indicates that, among all the infection types we studied, infection with IAV followed by RSV is associated with the highest IAV viral loads and the most morbidity and mortality.

scholarly journals An analysis of International Health Regulations Emergency Committees and Public Health Emergency of International Concern Designations

2020 ◽  
Vol 5 (6) ◽  
pp. e002502 ◽  
Author(s):  
Lucia Mullen ◽  
Christina Potter ◽  
Lawrence O Gostin ◽  
Anita Cicero ◽  
Jennifer B Nuzzo
Keyword(s):  
Public Health ◽  
Influenza A ◽  
Ebola Virus ◽  
Virus Disease ◽  
International Health ◽  
Public Health Emergency ◽  
Director General ◽  
International Health Regulations ◽  
International Response ◽  
Health Regulations

IntroductionNine events have been assessed for potential declaration of a Public Health Emergency of International Concern (PHEIC). A PHEIC is defined as an extraordinary event that constitutes a public health risk to other states through international spread and requires a coordinated international response. The WHO Director-General convenes Emergency Committees (ECs) to provide their advice on whether an event constitutes a PHEIC. The EC rationales have been criticised for being non-transparent and contradictory to the International Health Regulations (IHR). This first comprehensive analysis of EC rationale provides recommendations to increase clarity of EC decisions which will strengthen the IHR and WHO’s legitimacy in future outbreaks.Methods66 EC statements were reviewed from nine public health outbreaks of influenza A, Middle East respiratory syndrome coronavirus, polio, Ebola virus disease, Zika, yellow fever and coronavirus disease-2019. Statements were analysed to determine which of the three IHR criteria were noted as contributing towards the EC’s justification on whether to declare a PHEIC and what language was used to explain the decision.ResultsInterpretation of the criteria were often vague and applied inconsistently. ECs often failed to describe and justify which criteria had been satisfied.DiscussionGuidelines must be developed for the standardised interpretation of IHR core criteria. The ECs must clearly identify and justify which criteria have contributed to their rationale for or against PHEIC declaration.ConclusionStriving for more consistency and transparency in EC justifications would benefit future deliberations and provide more understanding and support for the process.

scholarly journals Multiple Incursions and Recurrent Epidemic Fade-Out of H3N2 Canine Influenza A Virus in the United States

2018 ◽  
Vol 92 (16) ◽  
Author(s):  
Ian E. H. Voorhees ◽  
Benjamin D. Dalziel ◽  
Amy Glaser ◽  
Edward J. Dubovi ◽  
Pablo R. Murcia ◽  
...  
Keyword(s):  
United States ◽  
Influenza A ◽  
The United States ◽  
Whole Genome Sequence ◽  
Whole Genome ◽  
Canine Influenza Virus ◽  
Emerging Virus ◽  
Avian Origin ◽  
Canine Influenza ◽  
Comprehensive Surveillance

ABSTRACT Avian-origin H3N2 canine influenza virus (CIV) transferred to dogs in Asia around 2005, becoming enzootic throughout China and South Korea before reaching the United States in early 2015. To understand the posttransfer evolution and epidemiology of this virus, particularly the cause of recent and ongoing increases in incidence in the United States, we performed an integrated analysis of whole-genome sequence data from 64 newly sequenced viruses and comprehensive surveillance data. This revealed that the circulation of H3N2 CIV within the United States is typified by recurrent epidemic burst–fade-out dynamics driven by multiple introductions of virus from Asia. Although all major viral lineages displayed similar rates of genomic sequence evolution, H3N2 CIV consistently exhibited proportionally more nonsynonymous substitutions per site than those in avian reservoir viruses, which is indicative of a large-scale change in selection pressures. Despite these genotypic differences, we found no evidence of adaptive evolution or increased viral transmission, with epidemiological models indicating a basic reproductive number, R0, of between 1 and 1.5 across nearly all U.S. outbreaks, consistent with maintained but heterogeneous circulation. We propose that CIV's mode of viral circulation may have resulted in evolutionary cul-de-sacs, in which there is little opportunity for the selection of the more transmissible H3N2 CIV phenotypes necessary to enable circulation through a general dog population characterized by widespread contact heterogeneity. CIV must therefore rely on metapopulations of high host density (such as animal shelters and kennels) within the greater dog population and reintroduction from other populations or face complete epidemic extinction. IMPORTANCE The relatively recent appearance of influenza A virus (IAV) epidemics in dogs expands our understanding of IAV host range and ecology, providing useful and relevant models for understanding critical factors involved in viral emergence. Here we integrate viral whole-genome sequence analysis and comprehensive surveillance data to examine the evolution of the emerging avian-origin H3N2 canine influenza virus (CIV), particularly the factors driving ongoing circulation and recent increases in incidence of the virus within the United States. Our results provide a detailed understanding of how H3N2 CIV achieves sustained circulation within the United States despite widespread host contact heterogeneity and recurrent epidemic fade-out. Moreover, our findings suggest that the types and intensities of selection pressures an emerging virus experiences are highly dependent on host population structure and ecology and may inhibit an emerging virus from acquiring sustained epidemic or pandemic circulation.

scholarly journals Are Ducks Contributing to the Endemicity of Highly Pathogenic H5N1 Influenza Virus in Asia?

2005 ◽  
Vol 79 (17) ◽  
pp. 11269-11279 ◽  
Author(s):  
K. M. Sturm-Ramirez ◽  
D. J. Hulse-Post ◽  
E. A. Govorkova ◽  
J. Humberd ◽  
P. Seiler ◽  
...  
Keyword(s):  
Influenza Virus ◽  
Influenza A ◽  
Virus Disease ◽  
Influenza Viruses ◽  
H5n1 Influenza Virus ◽  
Highly Pathogenic ◽  
Main Site ◽  
H5n1 Influenza ◽  
Pathogenic H5n1 ◽  
Virus Isolates

ABSTRACT Wild waterfowl are the natural reservoir of all influenza A viruses, and these viruses are usually nonpathogenic in these birds. However, since late 2002, H5N1 outbreaks in Asia have resulted in mortality among waterfowl in recreational parks, domestic flocks, and wild migratory birds. The evolutionary stasis between influenza virus and its natural host may have been disrupted, prompting us to ask whether waterfowl are resistant to H5N1 influenza virus disease and whether they can still act as a reservoir for these viruses. To better understand the biology of H5N1 viruses in ducks and attempt to answer this question, we inoculated juvenile mallards with 23 different H5N1 influenza viruses isolated in Asia between 2003 and 2004. All virus isolates replicated efficiently in inoculated ducks, and 22 were transmitted to susceptible contacts. Viruses replicated to higher levels in the trachea than in the cloaca of both inoculated and contact birds, suggesting that the digestive tract is not the main site of H5N1 influenza virus replication in ducks and that the fecal-oral route may no longer be the main transmission path. The virus isolates' pathogenicities varied from completely nonpathogenic to highly lethal and were positively correlated with tracheal virus titers. Nevertheless, the eight virus isolates that were nonpathogenic in ducks replicated and transmitted efficiently to naïve contacts, suggesting that highly pathogenic H5N1 viruses causing minimal signs of disease in ducks can propagate silently and efficiently among domestic and wild ducks in Asia and that they represent a serious threat to human and veterinary public health.

scholarly journals The multidisciplinary nature of COVID-19 research

2020 ◽  
Author(s):  
Ricardo Arencibia-Jorge ◽  
Lourdes García-García ◽  
Ernesto Galbán-Rodríguez ◽  
Humberto Carrillo-Calvet
Keyword(s):  
Influenza A Virus ◽  
Influenza A ◽  
Ebola Virus ◽  
Virus Disease ◽  
Scientific Output ◽  
Scientific Production ◽  
Political Impact ◽  
Multidisciplinary Nature ◽  
Human Infections ◽  
Bibliometric Measures

ABSTRACTObjectiveWe analyzed the scientific output after COVID-19 and contrasted it with studies published in the aftermath of seven epidemics/pandemics: Severe Acute Respiratory Syndrome (SARS), Influenza A virus H5N1 and Influenza A virus H1N1 human infections, Middle East Respiratory Syndrome (MERS), Ebola virus disease, Zika virus disease, and Dengue.Design/Methodology/ApproachWe examined bibliometric measures for COVID-19 and the rest of studied epidemics/pandemics. Data were extracted from Web of Science, using its journal classification scheme as a proxy to quantify the multidisciplinary coverage of scientific output. We proposed a novel Thematic Dispersion Index (TDI) for the analysis of pandemic early stages.Results/DiscussionThe literature on the seven epidemics/pandemics before COVID-19 has shown explosive growth of the scientific production and continuous impact during the first three years following each emergence or re-emergence of the specific infectious disease. A subsequent decline was observed with the progressive control of each health emergency. We observed an unprecedented growth in COVID-19 scientific production. TDI measured for COVID-19 (29,4) in just six months, was higher than TDI of the rest (7,5 to 21) during the first three years after epidemic initiation.ConclusionsCOVID-19 literature showed the broadest subject coverage, which is clearly a consecuence of its social, economic, and political impact. The proposed indicator (TDI), allowed the study of multidisciplinarity, differentiating the thematic complexity of COVID-19 from the previous seven epidemics/pandemics.Originality/ValueThe multidisciplinary nature and thematic complexity of COVID-19 research were successfully analyzed through a scientometric perspective.

EPIDEMIC INFLUENZA: A VIRUS DISEASE

The Lancet ◽  
1935 ◽  
Vol 225 (5828) ◽  
pp. 1118-1124 ◽  
Author(s):  
P.P. Laidlaw
Keyword(s):  
Influenza A Virus ◽  
Influenza A ◽  
Virus Disease

scholarly journals Knowledge, (mis-)conceptions, risk perception, and behavior change during pandemics: A scoping review of 149 studies

2020 ◽  
Vol 29 (8) ◽  
pp. 777-799
Author(s):  
Umair Majid ◽  
Aghna Wasim ◽  
Simran Bakshi ◽  
Judy Truong
Keyword(s):  
Risk Perception ◽  
Severe Acute Respiratory Syndrome ◽  
Behavior Change ◽  
Scoping Review ◽  
Risk Perceptions ◽  
Influenza A ◽  
Ebola Virus ◽  
Virus Disease ◽  
Influenza A H1n1 ◽  
And Behavior

The severe acute respiratory syndrome–coronavirus-2 pandemic has spread rapidly and has a growing impact on individuals, communities, and healthcare systems worldwide. At the core of any pandemic response is the ability of authorities and other stakeholders to react appropriately by promoting hygiene and social distancing behaviors. Successfully reaching this goal requires both individual and collective efforts to drastically modify daily routines and activities. There is a need to clarify how knowledge and awareness of disease influence risk perception, and subsequent behavior in the context of pandemics and global outbreaks. We conducted a scoping review of 149 studies spanning different regions and populations to examine the relationships between knowledge, risk perceptions, and behavior change. We analyzed studies on five major pandemics or outbreaks in the twenty-first century: severe acute respiratory syndrome, influenza A/H1N1, Middle East respiratory syndrome, Ebola virus disease, and coronavirus disease 2019.

scholarly journals A Model Survey for Assessing 2009 Pandemic Influenza A (H1N1) Virus Disease Burden in the Workplace

2011 ◽  
Vol 52 (suppl_1) ◽  
pp. S173-S176
Author(s):  
Jacqueline Gindler ◽  
Lisa A. Grohskopf ◽  
Matthew Biggerstaff ◽  
Lyn Finelli
Keyword(s):  
Pandemic Influenza ◽  
Influenza A ◽  
Disease Burden ◽  
H1n1 Virus ◽  
Virus Disease ◽  
Influenza A H1n1
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