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In Egypt, avian influenza A subtype H5N1 and H9N2 viruses are enzootic in poultry. The control plan devised by veterinary authorities in Egypt to prevent infections in poultry focused mainly on vaccination and ultimately failed. Recently, widespread H5N1 infections in poultry and a substantial increase in the number of human cases of H5N1 infection were observed. We summarize surveillance data from 2009 through 2014 and show that avian influenza viruses are established in poultry in Egypt and are continuously evolving genetically and antigenically. We also discuss the epidemiology of human infection with avian influenza in Egypt and describe how the true burden of disease is underestimated. We discuss the failures of relying on vaccinating poultry as the sole intervention tool. We conclude by highlighting the key components that need to be included in a new strategy to control avian influenza infections in poultry and humans in Egypt. [ABSTRACT FROM AUTHOR]

Highly Pathogenic Avian Influenza (HPAI) H5N1 virus is a threat to animal and public health worldwide. Till date, the H5N1 virus has claimed 402 human lives, with a mortality rate of 58% and has caused the death or culling of millions of poultry since 2003. In this study, we have designed three siRNAs (PB2-2235, PB2-479 and NP-865) targeting PB2 and NP genes of avian influenza virus and evaluated their potential, measured by hemagglutination (HA), plaque reduction and Real time RT-PCR assay, in inhibiting H5N1 virus (A/chicken/Navapur/7972/2006) replication in MDCK cells. The siRNAs caused 8- to 16-fold reduction in virus HA titers at 24 h after challenged with 100TCID of virus. Among these siRNAs, PB2-2235 offered the highest inhibition of virus replication with 16-fold reduction in virus HA titer, 80% reduction in viral plaque counts and 94% inhibition in expression of specific RNA at 24 h. The other two siRNAs had 68-73% and 87-88% reduction in viral plaque counts and RNA copy number, respectively. The effect of siRNA on H5N1 virus replication continued till 48h (maximum observation period). These findings suggest that PB2-2235 could efficiently inhibit HPAI H5N1 virus replication. [ABSTRACT FROM AUTHOR]

Avian influenza virus (AIV) was recovered from the internal contents of eggs, including mixture of albumen and allantoic fluid, and from the oviduct of naturally infected Japanese quail ( Coturnix coturnix japonica) flocks in the southern part of Thailand. The virus titers of 104.6-106.2 ELD50/mL were directly measured from the internal content of infected eggs. The virus was isolated by chorioallantoic sac inoculation of embryonating chicken eggs. Infected allantoic fluid was identified as hemagglutinating virus and then was indicated the presence of H5 hemagglutinin. The virus was confirmed to be H5N1 subtype influenza A virus by reverse transcriptase-polymerase chain reaction. Additionally, real-time reverse transcriptase-polymerase chain reaction assay could specifically detect influenza virus subtype H5. Furthermore, indirect fluorescent antibody (IFA) test by using specific anti-influenza A monoclonal antibody indicated that virus antigens were detected in the parenchyma of multiple tissues. Systemic localization of viral antigen detected was certainly considered to be viremic stage. In addition, influenza virus antigen was also detected by IFA in allantoic fluid sediments isolated from internal content of egg or oviduct. The conclusion of isolated AIV type A subtype H5N1 from these two infected materials was correlated to the viremic stage of infection because the virus antigens could be observed in almost all tissues. Conclusively, the need for adequate safeguards to prevent contamination and spread of the virus to the environment during movement of eggs—including hatching eggs, cracked eggs, and other relevant infected materials— or egg consumption from area of outbreak is emphasized and must not be ignored for the reasons of animal, public, and environmental health. [ABSTRACT FROM AUTHOR]