ABSTRACT
In late 2017, increased mortality was detected in chicken farms in Algeria undergoing A(H9N2) influenza outbreaks. Analysis of viruses isolated from affected farms showed that they were monophyletic, were of the G1 hemagglutinin (HA) lineage, and were antigenically and genetically similar to viruses detected contemporaneously in other countries in Northern Africa and the Middle East. The virus was able to spread via contact transmission between ferrets but did not cause disease in intravenously inoculated chickens.
Subject(s)
Disease Outbreaks/veterinary , Influenza A Virus, H9N2 Subtype/physiology , Influenza in Birds/epidemiology , Influenza in Birds/virology , Algeria/epidemiology , Animals , Chickens , Farms , Ferrets , Hemagglutination Inhibition Tests/veterinary , Hemagglutinin Glycoproteins, Influenza Virus/genetics , Hemagglutinin Glycoproteins, Influenza Virus/immunology , Influenza A Virus, H9N2 Subtype/classification , Influenza A Virus, H9N2 Subtype/genetics , Influenza A Virus, H9N2 Subtype/immunology , Influenza in Birds/diagnosis , Influenza in Birds/transmission , Neuraminidase/genetics , Phylogeny , Viral Load/veterinary , Viral Proteins/geneticsABSTRACT
Influenza viruses pose a major challenge to those concerned with global public health. Not only do influenza viruses cause yearly epidemics that are associated with slight changes in viral antigenicity, but occasionally new viruses cross from animal reservoirs into humans causing major pandemics. The most effective method to lower the mortality and morbidity associated with influenza is vaccination. In this review current and pending influenza vaccine technologies will be discussed in the context of both epidemic and pandemic influenza.