Appearance Of Influenza Research Articles

112. Sick Employee Online Log System for Tracking Employee Illnesses During the 2017–2018 Influenza Season Provided Real-Time Surveillance and Early Detection of Influenza-Like Illnesses Among Employees

BackgroundVidant Health is an 8-hospital, 1,542-bed system (including the 908-bed teaching hospital for The Brody School of Medicine at East Carolina University) with over 12,000 employees, and uses a sick employee online log (SEOL) to track illnesses among employees. Influenza-like illness (ILI) surveillance is collected from sentinel sites across the state of North Carolina (NC) by the Department of Health. Our goals were to determine the utility of the SEOL to monitor ILI among employees and to compare trends with the NC ILI-system for Influenza surveillance.MethodsWhen an employee calls in sick, symptoms for ILI in both the SEOL system and NC ILI-system include fever plus cough and/or sore throat. SEOL is an internet-based system, so information is collected and analyzed in real time. The number of sick hospital employees with influenza-like illness (ILI) per week during the 2017–2018 Influenza season was compared both to those employees reporting “Flu” and to the NC ILI numbers from the sentinel sites using MS Excel.ResultsThe data analyzed was from October 2017 to April 2018. First, while lesser actual numbers of sick employees reported “Flu,” there was a correlation value of 0.93 between those reporting “Flu” and those reporting ILI symptoms (see Figure 1). Secondly, the SEOL results are available daily, while the NC ILI data are reported 7–12 days from entry; however, the peaks in ILI paralleled those of the peaks in SEOL data for employees reporting symptoms of ILI (see Figure 2) with a correlation value of 0.79 between the two. Finally, there were no breaks in confidentiality for those employees utilizing the SEOL.ConclusionThe SEOL provided a real-time tool to monitor employee illnesses due to ILI during influenza season, and without the lag time of the ILI-surveillance by the state. This system maintained confidentiality with a convenient method for data entry. These findings conclude that the SEOL system data correlated positively with the state ILI data and provided an early detection system for the appearance of influenza among our employees. Disclosures All authors: No reported disclosures.

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

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.

Managing infections in pregnancy.

The management of infection in pregnancy aims mainly at improving the diagnosis and prognosis of congenital infections. Over 400 publications have dealt with this issue over the last 2 years, taking advantage of progress made not only in the epidemiological knowledge of infections but also neonatal treatment and prenatal diagnosis and interventions. The focus remains largely on viral and parasitic infections, namely cytomegalovirus (CMV) and toxoplasmosis, with the appearance of influenza as part of recent and severe outbreaks. The prevalence of CMV infection is stable. The prediction of foetal infection from primary maternal infection is becoming more accurate and therapeutic approaches are promising, including the development of a vaccine in the near future. The prevalence of toxoplasmosis is decreasing markedly in Europe weakening the effect of preventive measures and questioning the rationale for screening. In addition, the efficacy of prenatal treatment is still under scrutiny, although no appropriate randomized controlled trial (RCT) has been undertaken. Accurate dating of maternal primary infection is key to prenatal management including foetal and perinatal surveillance and therapy. Heightened prenatal surveillance following influenza infection in early pregnancy is warranted by an apparent increased risk of nonchromosomal congenital malformations in large epidemiological studies, likely as an effect of maternal hyperthermia.

Impact of influenza A(H1N1)pdm09 virus on circulation dynamics of seasonal influenza strains in Kenya.

We describe virus variations from patients with influenza-like illness before and after the appearance of influenza A(H1N1)pdm09 in Kenya during January 2008-July 2011. A total of 11,592 nasopharyngeal swabs were collected from consenting patients. Seasonal influenza B, A/H1N1, A/H3N2, A/H5N1, and influenza A(H1N1)pdm09 viruses were detected by real-time reverse transcription-polymerase chain reaction. Of patients enrolled, 2073 (17.9%) had influenza. A total of 1,524 (73.4%) of 2,073 samples were positive for influenza A virus and 549 (26.6%) were positive for influenza B virus. Influenza B virus predominated in 2008 and seasonal A(H1N1) virus predominated in the first half of 2009. Influenza A(H1N1)pdm09 virus predominated in the second half of 2009. Influenza A/H3N2 virus predominated in 2010, and co-circulation of influenza A(H1N1)pdm09 virus and influenza B virus predominated the first half of 2011. The reduction and displacement of seasonal A(H1N1) virus was the most obvious effect of the arrival of influenza A(H1N1)pdm09 virus. The decision of the World Health Organization to replace seasonal A(H1N1) virus with the pandemic virus strain for the southern hemisphere vaccine was appropriate for Kenya.

Pandemic influenza as 21st century urban public health crisis.

The percentage of the world's population living in urban areas will increase from 50% in 2008 to 70% (4.9 billion) in 2025. Crowded urban areas in developing and industrialized countries are uniquely vulnerable to public health crises and face daunting challenges in surveillance, response, and public communication. The revised International Health Regulations require all countries to have core surveillance and response capacity by 2012. Innovative approaches are needed because traditional local-level strategies may not be easily scalable upward to meet the needs of huge, densely populated cities, especially in developing countries. The responses of Mexico City and New York City to the initial appearance of influenza A pandemic (H1N1) 2009 virus during spring 2009 illustrate some of the new challenges and creative response strategies that will increasingly be needed in cities worldwide.

The Influenza-A mystery: insight from Bioinformatics resources and analysis.

Sir, Bioinformatics is a tool which can excavate any information, one wants to obtain. I found its implication in handling an emerging and highly pathogenic strain of Influenza virus, H5N1. The first influenza pandemic was happened in 1918 “Spanish flu” followed by Asian flu in 1957 caused by H2N2. Moreover, one million deaths were reported in Hong Kong due to H3N2 outbreak during 1968. The antigenic shift and drift of influenza A virus led to a new strain H1N1 in 1977 “Russian flu”. After two decades a new strain, H5N1 was evolved, called avian influenza virus. The outbreaks of this strain were continued till 2008 with the yearly epidemic in the world. In 2009, WHO has declared Influenza pandemic due to the outbreak of H1N1. The disease has infected over 35928 people in 80 countries, with 163 deaths. But it has been most severe in Mexico, which has reported the highest number of fatalities. The influenza virus is mysterious pathogen known for severe respiratory illness. It causes yearly epidemics in tropical and subtropical countries with epidemic and even pandemic flu, a major cause of morbidity and mortality. Recurrent appearance of influenza in different parts of the world is due to frequent mutations which may lead to either antigenic drift or shift. The structure of influenza A viral genome composed of eight segments of negative-sense single stranded RNA. Surface glycoprotein of influenza A virus, Hemagglutinin (HA) and Neuraminidase (NA) are the main components of viral genome to undergo reassortment and may cause to develop a new subtype or strain of Influenza virus. There are 16 different H antigens (H1 to H16) and nine different N antigens (N1 to N9). The latest H type (H16) was isolated from black-headed gulls found in Sweden and Netherlands during 1999 and was published in 2005. The history on influenza epidemic revealed circulation of these strains (H1N1, H2N2, H3N2, H5N1, H7N7, H1N2, H9N2, H7N2, H7N3, H5N2 and H10N7) among human, pig and bird population of different regions on the globe [1]. The strains appeared during outbreaks in different parts of the world and with the gap of different time periods could be analyzed for their phylogeny to understand their origin or source of spread. Phylogenetic trees are built by Neighbour-joining program with Kimura 2 parameter available at phylip3.65 package [2]. It is drawn by using TreeView1.6 program [3]. We can further analyze genome using GOR IV method [4]. Different domains/motifs were searched by “Composite” available at Expasy server [5]. Moreover, Amino acids sequences are also compared by MAP MUTATION program [6] to analyze the mutations among these isolates. Homology modeling of template structure related to proteins was searched using Blast algorithms against PDB. Amino acids sequence of PB1-F2 protein of A/HK/156/97 was obtain from Swiss-Prot [ID: {type:entrez-protein,attrs:{text:P0C0U0,term_id:83288374,term_text:P0C0U0}}P0C0U0]. Homology modeling of PB1-F2 from A/HK/156/97 (H5N1) based on crystal structure of PB1-F2 protein [PDB id: 2HN8] from H1N1 subtypes with ≫69% identity, was built by modeler [7]. Rigid body docking of PB1-F2 protein with VDAC1 and ANT3 was performed by HEX5.1 [8,9]. Each docking solution was minimized by energy minimization technique. Details of interaction derived from refined structures were analyzed using the LIGPLOT program [10]. It is trouble-free as well as time saving to understand the insight of microbial genome to answer several hidden mysteries and therefore, the origin of viral strains during an outbreak, by exploring these tools can easily be identified. The viral genome databases, available on different sources, NCBI [11] and IVDB [12] could be used to retrieve the sequences for analysis.

Two clusters of human infection with influenza A/H5N1 virus in the Republic of Azerbaijan, February-March 2006.

Following the appearance of influenza A/H5 virus infection in several wild and domestic bird species in the Republic of Azerbaijan in February 2006, two clusters of potential human avian influenza due to A/H5N1 (HAI) cases were detected and reported by the Ministry of Health (MoH) to the World Health Organization (WHO) Regional Office for Europe during the first two weeks of March 2006. On 15 March 2006, WHO led an international team, including infection control, clinical management, epidemiology, laboratory, and communications experts, to support the MoH in investigation and response activities. As a result of active surveillance, 22 individuals, including six deaths, were evaluated for HAI and associated risk infections in six districts. The investigations revealed eight cases with influenza A/H5N1 virus infection confirmed by a WHO Collaborating Centre for Influenza and one probable case for which samples were not available. The cases were in two unrelated clusters in Salyan (seven laboratory confirmed cases, including four deaths) and Tarter districts (one confirmed case and one probable case, both fatal). Close contact with and de-feathering of infected wild swans was considered to be the most plausible source of exposure to influenza A/H5N1 virus in the Salyan cluster, although difficulties in eliciting information were encountered during the investigation, because of the illegality of some of the activities that might have led to the exposures (hunting and trading in wild birds and their products). These cases constitute the first outbreak worldwide where wild birds were the most likely source of influenza A/H5N1 virus infection in humans. The rapid mobilisation of resources to contain the spread of influenza A/H5 in the two districts was achieved through collaboration between the MoH, WHO and its international partners. Control activities were supported by the establishment of a field laboratory with real-time polymerase chain reaction (RT-PCR) capacity to detect influenza A/H5 virus. Daily door-to-door surveillance undertaken in the two affected districts made it unlikely that human cases of influenza A/H5N1 virus infection remained undetected.

A rare appearance of influenza A(H1N2) as a reassortant in a community such as Yamagata where A(H1N1) and A(H3N2) co-circulate.

To find a new influenza subtype A(H1N2), 383 isolates identified as H1 by hemagglutination inhibition test between the 1998-1999 and 2001-2002 seasons in Yamagata, Japan, were screened by reverse transcription polymerase chain reaction. As a result, 3 strains from the 1999-2000 season were identified as possibly being A(H1N2). Although several of their clones were found to be A(H1N2), A(H1N1) and A(H3N2), we could not confirm the origin of the A(H1N2) clones without the original specimens. These results suggest that a reassortment to produce A(H1N2) does not readily occur even when A(H1N1) and A(H3N2) co-circulate in a community such as Yamagata.

Conceptional considerations for a German influenza pandemic preparedness plan.

A pandemic appearance of influenza A virus must be expected at any time. The limitations of health preserving and life-saving resources, which will inevitably be reached in the event of a pandemic, will be accompanied by ethical and possibly social conflicts, which can be lessened or resolved only through precautionary planning, clearly specified competencies and transparent decisions within a social consensus. In case of a shortage of vaccines and virostatic agents, decisions will have to be made with regard to the segment of the population that absolutely must be vaccinated. It is currently estimated that a (monovalent) vaccine developed for a new pandemic strain would only suffice for the single vaccination of approximately half of the German population after a year; only 10-14 million vaccine dosages would be available to provide basic immunization and single boosters to personnel required to maintain basic medical care and essential infrastructure after half a year. In the event of local influenza outbreaks, antiviral chemotherapeutic agents could be used to close the gap until a vaccine can become effective. Even if suitable influenza vaccines and virostatic agents are not sufficiently available at the start of a pandemic, it is still possible to at least prevent an outbreak of two of the most feared secondary infections that accompany influenza: pneumococcal pneumonia or meningitis and illnesses resulting from Haemophilus influenzae. Agreement still needs to be reached with manufacturers for guaranteeing the necessary vaccine production or ensuring that they have a sufficient stock to meet the minimum demand for antiviral agents and agents for symptomatic treatment.

Appearance of influenza A virus antigenic variants after treatment of infected MDCK cells with human leukocytes.

Exudation of polymorphonuclear leukocytes (PMN) from the infected mucosa is a characteristic feature of influenza virus infection. Since reactive oxygen species generated by PMN can be strong mutagens, the possibility of production of antigenic variants of the virus by virus-PMN interaction was investigated. Cloned influenza A NWS (H1N1) virus multiplying in Madin-Darby canine kidney cells was treated with human peripheral PMN. Assays in the presence and absence of monoclonal antibody to the cloned virus showed a seven- to ten-fold increase in the frequency of variants in the presence of PMN. The mutagenic effect was abolished by addition of superoxide dismutase to the culture.

Influenza in the United Kingdom 1982-85.

Influenza surveillance in the UK between the years 1982 and 1985 has demonstrated the regular winter appearance of influenza A virus of both H1N1 and H3N2 subtypes and influenza B. Their antigenic diversity is described and correlated with the national statistics for morbidity and mortality for influenza. One unexpected finding has been that despite the wide circulation of influenza viruses there has been a continuation of winters without significant increases in influenza deaths or morbidity. A previous report of influenza surveillance (Pereira & Chakraverty, 1982) noted an already unusual series of three consecutive winters with this pattern. This report records a further 4 years bringing a total of seven successive winters without evidence of epidemics of severe disease associated with influenza viruses, as indicated by the national UK statistics.

The effects of shifts and drifts on the epidemiology of influenza in man.

Accurate information on the epidemiology of influenza over the World is difficult to obtain as it is dependent on both national statistics of morbidity and mortality and on adequate virological confirmation of suspected cases. Only a few countries have the facilities for these and in much of the World it is difficult to establish exactly the impact of influenza. For this reason, our knowledge on the natural history of the disease and the virus causing it is restricted to what happens in a few areas of the World where the necessary information is obtainable. In one of these areas, the U.K., it has been possible to follow the appearance of influenza in successive years throughout the 11 years of prevalence of the H2N2 virus and throughout the 10 years of prevalence of the H3N2 virus. What are still unknown are the factors that determine this pattern. Various hypotheses have been proposed to explain the epidemiology of influenza.

RAPID DIAGNOSIS OF INFLUENZA A INFECTION BY IMMUNOFLUORESCENCE

Indirect immunofluorescence (IF) on cell spreads from nasopharyngeal secretions (NPS) was used for the rapid diagnosis of influenza A infection and was compared with IF on monkey kidney cells infected by NPS. The clinical diagnosis of influenza A infection was confirmed by serology in 32 of 40 patients. In 27 of the 32 patients (84 per cent), the diagnosis was achieved by IF on cell spreads of NPS. In 13 of 15 (87 per cent) subjects with positive serology, the early appearance of influenza A virus antigen was revealed by indirect IF on infected monolayer cells. No false positive specimens were found among serologically negative subjects by either method. Consequently, the reliability of IF on cell spreads of NPS is very similar to IF on infected cell cultures, but offers a much quicker diagnosis (3-4 h as compared to 1-3 d). Monovalent anti-human IgG FITC should be used instead of polyvalent anti-human Ig FITC, as the latter contains anti-IgA which may adhere to intracellular IgA in the epithelial cells of NPS and thereby cloak the viral antigen.

Respiratory viral infections 1976

During an influenza surveillance programme initiated by the New Zealand Department of Health, the Dunedin Hospital Virus Diagnostic Laboratory was able to study an epidemic of influenza A infection which occurred in the winter months of 1976. From mid-May through to mid-July there were 251 influenza isolations (A/Victoria/3/75) made from 247 patients and serology confirmed a further 26 cases. A total of 660 throat swabs were examined. The majority of the confirmed cases occurred in Christchurch and Dunedin but isolations were obtained from patients from Timaru and Invercargill and the country townships of Balclutha. Ranfurly and Winton. Surveillance covered an estimated population of 400.000 and the overall attack rate was in the order of 20–25%. Symptoms ranged from severe pneumonia to mild fever and sore throat, with all age groups being affected. Many adolescents and young adults experienced particularly severe illnesses as compared with other influenza outbreaks in the 1970s. In Dunedin 4 deaths were attributable to uncomplicated influenzal pneumonia. University colleges and secondary school boarding hostels in Dunedin experienced major outbreaks of the disease. Parainfluenza virus type 2 infections were confirmed during the influenza epidemic. A few cases of influenza were reported at a Dunedin women's boarding hostel in February when influenza activity was confirmed in the North Island of New Zealand. This unexpected appearance of influenza in late summer was followed by an absence of the disease in March and April during which an extended ‘enterovirus season’ gave rise to respiratory infections with Echovirus type 19 and Coxsackievirus group B4.