WHO: Warning signals from the volatile world of influenza viruses

February 2015

The current global influenza situation is characterized by a number of trends that must be closely monitored. These include: an increase in the variety of animal influenza viruses co-circulating and exchanging genetic material, giving rise to novel strains; continuing cases of human H7N9 infections in China; and a recent spurt of human H5N1 cases in Egypt. Changes in the H3N2 seasonal influenza viruses, which have affected the protection conferred by the current vaccine, are also of particular concern.

Viruses in wild and domestic birds

The diversity and geographical distribution of influenza viruses currently circulating in wild and domestic birds are unprecedented since the advent of modern tools for virus detection and characterization. The world needs to be concerned.

Viruses of the H5 and H7 subtypes are of greatest concern, as they can rapidly mutate from a form that causes mild symptoms in birds to one that causes severe illness and death in poultry populations, resulting in devastating outbreaks and enormous losses to the poultry industry and to the livelihoods of farmers.

Since the start of 2014, the Organisation for Animal Health, or OIE, has been notified of 41 H5 and H7 outbreaks in birds involving 7 different viruses in 20 countries in Africa, the Americas, Asia, Australia, Europe, and the Middle East. Several are novel viruses that have emerged and spread in wild birds or poultry only in the past few years.

Some of the outbreaks notified to OIE have involved wild birds only. Such notifications are indicative of the heightened surveillance and improved laboratory detection that have followed the massive outbreaks of highly pathogenic H5N1 avian influenza that began in Asia in late 2003.

Detection of highly pathogenic avian influenza viruses in wild birds signals the need for a close watch over poultry farms. Migratory waterfowl, immune to the disease, are known to spread avian viruses to new areas by quickly crossing continents along the routes of several flyways. These migratory waterfowl subsequently mix with local wild birds and poultry that then become infected.

Click HERE to read the complete WHO article.
http://www.who.int/influenza/publications/warningsignals201502/en/

Avian influenza and the role of migratory and domestic birds

The Modes of Evolutionary Emergence of Primal and Late Pandemic Influenza Virus Strains from Viral Reservoir in Animals: An Interdisciplinary Analysis
Dany Shoham
The Begin-Sadat Center for Strategic Studies, Bar-Ilan University, Ramat Gan 52900, Israel

Received 30 June 2011; Accepted 30 August 2011

Academic Editor: Zichria Zakay-Rones

Copyright © 2011 Dany Shoham. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract
Based on a wealth of recent findings, in conjunction with earliest chronologies pertaining to evolutionary emergences of ancestral RNA viruses, ducks, Influenzavirus A (assumingly within ducks), and hominids, as well as to the initial domestication of mallard duck (Anas platyrhynchos), jungle fowl (Gallus gallus), wild turkey (Meleagris gallopavo), wild boar (Sus scrofa), and wild horse (Equus ferus), presumed genesis modes of primordial pandemic influenza strains have multidisciplinarily been configured. The virological fundamentality of domestication and farming of those various avian and mammalian species has thereby been demonstrated and broadly elucidated, within distinctive coevolutionary paradigms. The mentioned viral genesis modes were then analyzed, compatibly with common denominators and flexibility that mark the geographic profile of the last 18 pandemic strains, which reputedly emerged since 1510, the antigenic profile of the last 10 pandemic strains since 1847, and the genomic profile of the last 5 pandemic strains since 1918, until present. Related ecophylogenetic and biogeographic aspects have been enlightened, alongside with the crucial role of spatial virus gene dissemination by avian hosts. A fairly coherent picture of primary and late evolutionary and genomic courses of pandemic strains has thus been attained, tentatively. Specific patterns underlying complexes prone to generate past and future pandemic strains from viral reservoir in animals are consequentially derived.

Click HERE for the complete paper.
http://www.hindawi.com/journals/irt/2011/861792/