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1.
Emerg Microbes Infect ; 6(1): e1, 2017 Jan 04.
Article in English | MEDLINE | ID: mdl-28050021

ABSTRACT

Middle East respiratory syndrome coronavirus (MERS-CoV) causes severe human infections and dromedary camels are considered an intermediary host. The dynamics of natural infection in camels are not well understood. Through systematic surveillance in Egypt, nasal, rectal, milk, urine and serum samples were collected from camels between June 2014 and February 2016. Locations included quarantines, markets, abattoirs, free-roaming herds and farmed breeding herds. The overall seroprevalence was 71% and RNA detection rate was 15%. Imported camels had higher seroprevalence (90% vs 61%) and higher RT-PCR detection rates (21% vs 12%) than locally raised camels. Juveniles had lower seroprevalence than adults (37% vs 82%) but similar RT-PCR detection rates (16% vs 15%). An outbreak in a breeding herd, showed that antibodies rapidly wane, that camels become re-infected, and that outbreaks in a herd are sustained for an extended time. Maternal antibodies titers were very low in calves regardless of the antibody titers of the mothers. Our results support the hypothesis that camels are a reservoir for MERS-CoV and that camel trade is an important route of introducing the virus into importing countries. Findings related to waning antibodies and re-infection have implications for camel vaccine development, disease management and zoonotic threat.


Subject(s)
Camelus/virology , Coronavirus Infections/veterinary , Epidemiological Monitoring , Middle East Respiratory Syndrome Coronavirus/isolation & purification , Molecular Diagnostic Techniques , Serologic Tests , Animals , Antibodies, Viral/blood , Body Fluids/virology , Cattle , Coronavirus Infections/diagnosis , Coronavirus Infections/epidemiology , Disease Outbreaks , Egypt/epidemiology , Female , Male , Middle East Respiratory Syndrome Coronavirus/genetics , Middle East Respiratory Syndrome Coronavirus/immunology , Nasal Mucosa/virology , RNA, Viral/analysis , Rectum/virology , Reverse Transcriptase Polymerase Chain Reaction , Seroepidemiologic Studies
2.
Emerg Infect Dis ; 22(3): 379-88, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26886164

ABSTRACT

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.


Subject(s)
Influenza A Virus, H5N1 Subtype , Influenza A Virus, H9N2 Subtype , Influenza in Birds/epidemiology , Poultry Diseases/virology , Poultry/virology , Animals , Egypt/epidemiology , Epidemiological Monitoring/veterinary , Humans , Influenza A Virus, H5N1 Subtype/genetics , Influenza A Virus, H9N2 Subtype/genetics , Influenza Vaccines , Influenza in Birds/prevention & control , Influenza in Birds/virology , Influenza, Human/epidemiology , Influenza, Human/virology , Poultry Diseases/epidemiology , Poultry Diseases/prevention & control
3.
Arch Virol ; 159(11): 2861-76, 2014 Nov.
Article in English | MEDLINE | ID: mdl-24990416

ABSTRACT

Avian influenza virus subtype H9N2 has been circulating in the Middle East since the 1990s. For uncertain reasons, H9N2 was not detected in Egyptian farms until the end of 2010. Circulation of H9N2 viruses in Egyptian poultry in the presence of the enzootic highly pathogenic H5N1 subtype adds a huge risk factor to the Egyptian poultry industry. In this study, 22 H9N2 viruses collected from 2011 to 2013 in Egypt were isolated and sequenced. The genomic signatures and protein sequences of these isolates were analyzed. Multiple mammalian-host-associated mutations were detected that favor transmission from avian to mammalian hosts. Other mutations related to virulence were also identified. Phylogenetic data showed that Egyptian H9N2 viruses were closely related to viruses isolated from neighboring Middle Eastern countries, and their HA gene resembled those of viruses of the G1-like lineage. No reassortment was detected with H5N1 subtypes. Serological analysis of H9N2 virus revealed antigenic conservation among Egyptian isolates. Accordingly, continuous surveillance that results in genetic and antigenic characterization of H9N2 in Egypt is warranted.


Subject(s)
Antigens, Viral/genetics , Evolution, Molecular , Influenza A Virus, H9N2 Subtype/genetics , Influenza A Virus, H9N2 Subtype/immunology , Influenza in Birds/virology , Poultry Diseases/virology , Viral Proteins/genetics , Amino Acid Sequence , Animals , Antigens, Viral/chemistry , Antigens, Viral/immunology , Egypt/epidemiology , Influenza A Virus, H9N2 Subtype/classification , Influenza A Virus, H9N2 Subtype/isolation & purification , Influenza in Birds/epidemiology , Molecular Sequence Data , Phylogeny , Poultry , Poultry Diseases/epidemiology , Sequence Alignment , Viral Proteins/chemistry , Viral Proteins/immunology
4.
J Gen Virol ; 95(Pt 7): 1444-1463, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24722680

ABSTRACT

Clade 2.2 highly pathogenic H5N1 viruses have been in continuous circulation in Egyptian poultry since 2006. Their persistence caused significant genetic drift that led to the reclassification of these viruses into subclades 2.2.1 and 2.2.1.1. Here, we conducted full-genome sequence and phylogenetic analyses of 45 H5N1 isolated during 2006-2013 through systematic surveillance in Egypt, and 53 viruses that were sequenced previously and available in the public domain. Results indicated that H5N1 viruses in Egypt continue to evolve and a new distinct cluster has emerged. Mutations affecting viral virulence, pathogenicity, transmission, receptor-binding preference and drug resistance were studied. In light of our findings that H5N1 in Egypt continues to evolve, surveillance and molecular studies need to be sustained.


Subject(s)
Influenza A Virus, H5N1 Subtype/classification , Influenza A Virus, H5N1 Subtype/genetics , Influenza in Birds/virology , Poultry , Animals , Cluster Analysis , Egypt , Genotype , Influenza A Virus, H5N1 Subtype/isolation & purification , Molecular Sequence Data , Phylogeny , RNA, Viral/genetics , Sequence Analysis, DNA
5.
Emerg Infect Dis ; 20(4): 542-51, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24655395

ABSTRACT

Continuous circulation of influenza A(H5N1) virus among poultry in Egypt has created an epicenter in which the viruses evolve into newer subclades and continue to cause disease in humans. To detect influenza viruses in Egypt, since 2009 we have actively surveyed various regions and poultry production sectors. From August 2010 through January 2013, >11,000 swab samples were collected; 10% were positive by matrix gene reverse transcription PCR. During this period, subtype H9N2 viruses emerged, cocirculated with subtype H5N1 viruses, and frequently co-infected the same avian host. Genetic and antigenic analyses of viruses revealed that influenza A(H5N1) clade 2.2.1 viruses are dominant and that all subtype H9N2 viruses are G1-like. Cocirculation of different subtypes poses concern for potential reassortment. Avian influenza continues to threaten public and animal health in Egypt, and continuous surveillance for avian influenza virus is needed.


Subject(s)
Influenza in Birds/epidemiology , Animals , Birds/virology , Egypt/epidemiology , Influenza A Virus, H5N1 Subtype/genetics , Influenza A Virus, H9N2 Subtype/genetics
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