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Vet Microbiol. 2016 Sep 25;193:49-59. doi: 10.1016/j.vetmic.2016.07.025. Epub 2016 Aug 2.
Surveillance, epidemiological, and virological detection of highly pathogenic H5N1 avian influenza viruses in duck and poultry from Bangladesh.
Ansari WK1, Parvej MS1, El Zowalaty ME2, Jackson S1, Bustin SA3, Ibrahim AK4, El Zowalaty AE5, Rahman MT1, Zhang H6, Khan MF1, Ahamed MM1, Rahman MF7, Rahman M1, Nazir KH1, Ahmed S1, Hossen ML1, Kafi MA1, Yamage M8, Debnath NC8, Ahmed G8, Ashour HM9, Masudur Rahman M10, Noreddin A11, Rahman MB12.
Author information
Abstract
Avian influenza viruses (AIVs) continue to pose a global threat. Waterfowl are the main reservoir and are responsible for the spillover of AIVs to other hosts. This study was conducted as part of routine surveillance activities in Bangladesh and it reports on the serological and molecular detection of H5N1 AIV subtype. A total of 2169 cloacal and 2191 oropharyngeal swabs as well as 1725 sera samples were collected from live birds including duck and chicken in different locations in Bangladesh between the years of 2013 and 2014. Samples were tested using virus isolation, serological tests and molecular methods of RT-PCR. Influenza A viruses were detected using reverse transcription PCR targeting the virus matrix (M) gene in 41/4360 (0.94%) samples including both cloacal and oropharyngeal swab samples, 31 of which were subtyped as H5N1 using subtype-specific primers. Twenty-one live H5N1 virus isolates were recovered from those 31 samples. Screening of 1,868 blood samples collected from the same birds using H5-specific ELISA identified 545/1603 (34%) positive samples. Disconcertingly, an analysis of 221 serum samples collected from vaccinated layer chicken in four districts revealed that only 18 samples (8.1%) were seropositive for anti H5 antibodies, compared to unvaccinated birds (n=105), where 8 samples (7.6%) were seropositive. Our result indicates that the vaccination program as currently implemented should be reviewed and updated. In addition, surveillance programs are crucial for monitoring the efficacy of the current poultry vaccinations programs, and to monitor the circulating AIV strains and emergence of AIV subtypes in Bangladesh.
Copyright ? 2016. Published by Elsevier B.V.
KEYWORDS:
Avian Influenza; Bangladesh; Duck; H5N1; Influenza A virus; Isolation; Live bird markets; Poultry; Reverse transcription polymerase chain reaction; Surveillance; Virus; Wild birds
PMID: 27599930 DOI: 10.1016/j.vetmic.2016.07.025
[PubMed - in process]
Surveillance, epidemiological, and virological detection of highly pathogenic H5N1 avian influenza viruses in duck and poultry from Bangladesh.
Ansari WK1, Parvej MS1, El Zowalaty ME2, Jackson S1, Bustin SA3, Ibrahim AK4, El Zowalaty AE5, Rahman MT1, Zhang H6, Khan MF1, Ahamed MM1, Rahman MF7, Rahman M1, Nazir KH1, Ahmed S1, Hossen ML1, Kafi MA1, Yamage M8, Debnath NC8, Ahmed G8, Ashour HM9, Masudur Rahman M10, Noreddin A11, Rahman MB12.
Author information
Abstract
Avian influenza viruses (AIVs) continue to pose a global threat. Waterfowl are the main reservoir and are responsible for the spillover of AIVs to other hosts. This study was conducted as part of routine surveillance activities in Bangladesh and it reports on the serological and molecular detection of H5N1 AIV subtype. A total of 2169 cloacal and 2191 oropharyngeal swabs as well as 1725 sera samples were collected from live birds including duck and chicken in different locations in Bangladesh between the years of 2013 and 2014. Samples were tested using virus isolation, serological tests and molecular methods of RT-PCR. Influenza A viruses were detected using reverse transcription PCR targeting the virus matrix (M) gene in 41/4360 (0.94%) samples including both cloacal and oropharyngeal swab samples, 31 of which were subtyped as H5N1 using subtype-specific primers. Twenty-one live H5N1 virus isolates were recovered from those 31 samples. Screening of 1,868 blood samples collected from the same birds using H5-specific ELISA identified 545/1603 (34%) positive samples. Disconcertingly, an analysis of 221 serum samples collected from vaccinated layer chicken in four districts revealed that only 18 samples (8.1%) were seropositive for anti H5 antibodies, compared to unvaccinated birds (n=105), where 8 samples (7.6%) were seropositive. Our result indicates that the vaccination program as currently implemented should be reviewed and updated. In addition, surveillance programs are crucial for monitoring the efficacy of the current poultry vaccinations programs, and to monitor the circulating AIV strains and emergence of AIV subtypes in Bangladesh.
Copyright ? 2016. Published by Elsevier B.V.
KEYWORDS:
Avian Influenza; Bangladesh; Duck; H5N1; Influenza A virus; Isolation; Live bird markets; Poultry; Reverse transcription polymerase chain reaction; Surveillance; Virus; Wild birds
PMID: 27599930 DOI: 10.1016/j.vetmic.2016.07.025
[PubMed - in process]