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Heterosubtypic Immunity to Influenza A Virus Infections in Mallards May Explain Existence of Multiple Virus Subtypes

Wild birds, particularly duck species, are the main reservoir of influenza A virus (IAV) in nature. However, knowledge of IAV infection dynamics in the wild bird reservoir, and the development of immune responses, are essentially absent. Importantly, a detailed understanding of how subtype diversity is generated and maintained is lacking. To address this, 18,679 samples from 7728 Mallard ducks cap

Disease dynamics and bird migration-linking mallards Anas platyrhynchos and subtype diversity of the influenza a virus in time and space

The mallard Anas platyrhynchos is a reservoir species for influenza A virus in the northern hemisphere, with particularly high prevalence rates prior to as well as during its prolonged autumn migration. It has been proposed that the virus is brought from the breeding grounds and transmitted to conspecifics during subsequent staging during migration, and so a better understanding of the natal origi

Birds and Viruses at a Crossroad - Surveillance of Influenza A Virus in Portuguese Waterfowl

During recent years, extensive amounts of data have become available regarding influenza A virus (IAV) in wild birds in northern Europe, while information from southern Europe is more limited. Here, we present an IAV surveillance study conducted in western Portugal 2008-2009, analyzing 1653 samples from six different species of waterfowl, with the majority of samples taken from Mallards (Anas plat

Avian influenza surveillance with FTA cards : Field methods, biosafety, and transportation issues solved

Avian Influenza Viruses (AIVs) infect many mammals, including humans1. These AIVs are diverse in their natural hosts, harboring almost all possible viral subtypes2. Human pandemics of flu originally stem from AIVs3. Many fatal human cases during the H5N1 outbreaks in recent years were reported. Lately, a new AIV related strain swept through the human population, causing the 'swine flu epidemic'4.

Environmental levels of the antiviral oseltamivir induce development of resistance mutation H274Y in influenza A/H1N1 virus in mallards

Oseltamivir (Tamiflu®) is the most widely used drug against influenza infections and is extensively stockpiled worldwide as part of pandemic preparedness plans. However, resistance is a growing problem and in 2008-2009, seasonal human influenza A/H1N1 virus strains in most parts of the world carried the mutation H274Y in the neuraminidase gene which causes resistance to the drug. The active metabo

Degenerate primers for PCR amplification and sequencing of the avian influenza A neuraminidase gene

This study describes the design of degenerate primers and their use for synthesis of full-length avian influenza A neuramindase (NA). Each reaction was performed using either two forward primers and one reverse primer, or one forward primer and one reverse primer. Both primer combinations had comparable amplification efficiencies for all NA subtypes (1-9). A total of 115 virus strains, including b

Influenza virus in a natural host, the mallard : Experimental infection data

Wild waterfowl, particularly dabbling ducks such as mallards (Anas platyrhynchos), are considered the main reservoir of low-pathogenic avian influenza viruses (LPAIVs). They carry viruses that may evolve and become highly pathogenic for poultry or zoonotic. Understanding the ecology of LPAIVs in these natural hosts is therefore essential. We assessed the clinical response, viral shedding and antib

Zero prevalence of influenza A virus in two raptor species by standard screening

Disease can have severe impact on animal populations, especially in rare species. Baseline data for atypical host species are missing for a range of infectious diseases, although such hosts are potentially more affected than the normal vectors and reservoir species. If highly pathogenic avian influenza strikes rare birds of prey, this may have crucial impact on the predator species itself, but als

Avian influenza surveillance : On the usability of FTA®cards to solve biosafety and transport issues

Many zoonotic diseases have birds as their natural hosts. Waterfowl are the natural hosts of avian influenza viruses (AIVs) and most avian influenza infections of wild birds appear mild, with infected inviduals displaying no or few symptoms. It is clear that the epidemiology of avian influenza cannot be fully understood without taking the ecology of its hosts into account. However, large scale stu

Carbonaceous aerosol source apportionment using the Aethalometer model -evaluation by radiocarbon and levoglucosan analysis at a rural background site in southern Sweden

With the present demand on fast and inexpensive aerosol source apportionment methods, the Aethalometer model was evaluated for a full seasonal cycle (June 2014–June 2015) at a rural atmospheric measurement station in southern Sweden by using radiocarbon and levoglucosan measurements. By utilizing differences in absorption of UV and IR, the Aethalometer model apportions carbon mass into wood burnin

Of ducks and men : ecology and evolution of a zoonotic pathogen in a wild reservoir host

A hallmark of disease is that most pathogens are able to infect more than one host species. However, for most pathogens, we still have a limited understanding of how this affects epidemiology, persistence and virulence of infections—including several zoonotic pathogens that reside in wild animal reservoirs and spillover into humans. In this chapter, we review the current knowledge of mallard (Anas

Institutional complexity and private authority in global climate governance : The cases of climate engineering, REDD+, and short-lived climate pollutants

How and why do institutional architectures, and the roles of private institutions therein, differ across separate areas of climate governance? Here, institutional complexity is explained in terms of the problem-structural characteristics of an issue area and the associated demand for, and supply of, private authority. These characteristics can help explain the degree of centrality of intergovernme

Byggnadstekniskt brandskydd i MSB:s utbildningar

The primary purpose of this work was to study and analyze the MSB's training with respect to building fire protection and propose changes in training. The area studied is operational aspects of building fire protection, ie how this protection affects the ability to implement effective response from fire service organizations. The main conclusions were that the training must distinguish between new

Utveckling av utbildning för RIB, räddningstjänstpersonal i beredskap

The objective of the present work was to create a basis for further development on training for part-time firefighters. An important prerequisite of this work was that to the general public a firefighter is a firefighter and operations are expected to be conducted in the same manner, with similar efficiency and with good result, regardless of the type of resources arriving at the scene of an accid