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1.
Br Poult Sci ; 65(1): 28-33, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38038674

RESUMO

1. The effectiveness of inactivated vaccines depends on selecting the suitable adjuvant for vaccine formulation. The potency of vaccines with low antigen content can be improved with the appropriate adjuvant. This could allow production of more doses and lower the production cost.2. This study evaluated the efficiency of vaccines prepared using oil extracted from natural sources including argan oil, almond oil, sesame seed oil, pumpkin oil, cactus oil and black seed oil as alternative adjuvants for improving the protection capacity of inactivated influenza virus vaccine as compared to commonly used mineral oils.3. Each vaccine formulation was evaluated for stability, safety and immunogenicity in chickens, as well as for reducing the viral shedding after challenge infection.4. The cactus, sesame and pumpkin seed oil-based vaccines were found to be potent and successfully induced the production of humoral immunity in vaccinated chickens.


Assuntos
Vacinas contra Influenza , Influenza Aviária , Animais , Galinhas , Óleo Mineral , Óleos de Plantas , Influenza Aviária/prevenção & controle , Minerais
2.
East Mediterr Health J ; 22(7): 491-502, 2016 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-27714744

RESUMO

Understanding the genetic evolution of A(H1N1)pdm09 and H3N2 viruses can help better select strains to be included in the annual influenza vaccine. There is little information on their evolution in Jordan so this study investigated the genetic and antigenic variability of A(H1N1)pdm09 and H3N2 viruses in Jordan by performing phylogenetic and genetic analyses of the HA and NA genes of A(H1N1)pdm09 and H3N2 viruses between 2011 and 2013. The full HA and NA genes of 16 H1N1-positive samples obtained in our study and 21 published HA sequences and 20 published NA sequences from Jordanian viruses that were available on online gene databases were analysed. For H3N2, we generated 20 HA and 19 NA sequences and included 19 published HA and NA sequences each in the analysis. Jordanian H1N1 viruses had mutations that are characteristic of antigenic group 6 while H3N2 virus mutations belonged to group 3. No markers of resistance to oseltamivir were detected. The individual mutations are described in detail.


Assuntos
Evolução Molecular , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H3N2/genética , Epidemiologia Molecular , Humanos , Influenza Humana/epidemiologia , Jordânia/epidemiologia
3.
East Mediterr Health J ; 22(7): 557-561, 2016 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-27714751

RESUMO

Surveillance for avian influenza viruses in Egyptian poultry has been conducted since 2009. Up to 2011, all the detected viruses were H5N1, and the overall prevalence was 5%. In 2011, H9N2 viruses were observed to be co-circulating and co-infecting the same hosts as H5N1 viruses. Since then, the detection rate has increased to around 10%. In the 2014-2015 winter season, H5N1 was circulating heavily in poultry flocks and caused an unprecedented number of human infections. In contrast, surveillance in the last quarter of 2015 indicated a near absence of H5N1 in Egyptian poultry. Surveillance for avian influenza viruses must continue in Egypt to monitor further developments in H5N1 circulation in poultry.


Assuntos
Virus da Influenza A Subtipo H5N1/isolamento & purificação , Vírus da Influenza A Subtipo H9N2/isolamento & purificação , Vigilância da População/métodos , Aves Domésticas/virologia , Animais , Egito/epidemiologia , Humanos , Influenza Aviária , Sorotipagem
4.
East. Mediterr. health j ; 22(7): 553-557, 2016-07.
Artigo em Inglês | WHO IRIS | ID: who-260107

RESUMO

Surveillance for avian influenza viruses in Egyptian poultry has been conducted since 2009. Up to 2011, all the detected viruses were H5N1, and the overall prevalence was 5%. In 2011, H9N2 viruses were observed to be co-circulating and co-infecting the same hosts as H5N1 viruses. Since then, the detection rate has increased to around 10%. In the 2014-2015 winter season, H5N1 was circulating heavily in poultry flocks and caused an unprecedented number of human infections. In contrast, surveillance in the last quarter of 2015 indicated a near absence of H5N1 in Egyptian poultry. Surveillance for avian influenza viruses must continue in Egypt to monitor further developments in H5N1 circulation in poultry


La surveillance des virus de la grippe aviaire dans les populations de volailles égyptiennes est en cours depuis 2009. Jusqu'à 2011, tous les virus détectés appartenaient au H5N1, et la prévalence générale était de 5%. En 2011, on a remarqué que les virus H9N2 circulaient en même temps et co-infectaient les mêmes hôtes que les virus H5N1. Depuis, le taux de détection a augmenté pour atteindre près de 10%. Pendant la saison hivernale 2014-2015, le virus H5N1 a considérablement circulé dans les élevages de volailles, entraînant un nombre d'infections sans précédent chez l'homme. A l'inverse, la surveillance au cours du dernier trimestre 2015 a constaté la quasi-absence du H5N1 dans les populations de volailles égyptiennes. La surveillance des virus de la grippe aviaire doit se poursuivre en Egypte afin de déceler les futures évolutions de la circulation du H5N1 dans les populations de volailles


Assuntos
Doenças Transmissíveis , Influenza Aviária , Virus da Influenza A Subtipo H5N1 , Orthomyxoviridae , Aves Domésticas , Influenza Humana
5.
East. Mediterr. health j ; 22(7): 490-498, 2016-07.
Artigo em Inglês | WHO IRIS | ID: who-260100

RESUMO

Understanding the genetic evolution of A [H1N1]pdm09 and H3N2 viruses can help better select strains to be included in the annual influenza vaccine. There is little information on their evolution in Jordan so this study investigated the genetic and antigenic variability of A[H1N1]pdm09 and H3N2 viruses in Jordan by performing phylogenetic and genetic analyses of the HA and NA genes of A[H1N1]pdm09 and H3N2 viruses between 2011 and 2013. The full HA and NA genes of 16 H1N1-positive samples obtained in our study and 21 published HA sequences and 20 published NA sequences from Jordanian viruses that were available on online gene databases were analysed. For H3N2, we generated 20 HA and 19 NA sequences and included 19 published HA and NA sequences each in the analysis. Jordanian H1N1 viruses had mutations that are characteristic of antigenic group 6 while H3N2 virus mutations belonged to group 3. No markers of resistance to oseltamivir were detected. The individual mutations are described in detail


La compréhension de l'évolution génétique des virus A[H1N1]pdm09 et H3N2 permet de mieux sélectionner les souches devant être ajoutées au vaccin antigrippal annuel. Peu de renseignements sont disponibles sur les mutations des virus saisonniers de la grippe A[H1N1]pdm09 et H3N2 en Jordanie. Afin de remédier à ce problème et d'étudier les variations génétiques et antigéniques des virus A[H1N1]pdm09 et H3N2, nous avons procédé à des analyses génétiques et phylogénétiques des gènes de l'hémagglutinine [HA] et de la neuraminidase [NA] de ces virus, sur la période 2011-2013 en Jordanie. L'analyse a porté sur les séquences complètes des gènes de l'HA et de la NA de 16 échantillons positifs au virus H1N1 prélevés dans le cadre de cette étude, ainsi que sur 21 séquences publiées de l'HA et 20 séquences publiées de la NA, issues de virus jordaniens disponibles sur les bases de données de gènes en ligne. Pour le virus H3N2, nous avons généré 20 séquences de l'HA et 19 de la NA, et avons également inclus dans l'analyse 19 séquences publiées de l'HA et 19 de la NA. Les virus H1N1 jordaniens présentaient des mutations caractéristiques du groupe antigénique 6, tandis que les virus H3N2 appartenaient au groupe 3. Aucun marqueur de résistance à l'oseltamivir n'a été détecté. Les mutations individuelles sont décrites en detail


Assuntos
Doenças Transmissíveis , Vírus da Influenza A Subtipo H1N1 , Vírus da Influenza A Subtipo H3N2 , Vacinas contra Influenza , Oseltamivir , Bases de Dados Genéticas , Estudos Prospectivos , Estudos de Coortes , Reação em Cadeia da Polimerase
6.
Euro Surveill ; 19(23)2014 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-24957744

RESUMO

The pseudoparticle virus neutralisation test (ppNT) and a conventional microneutralisation (MN) assay are specific for detecting antibodies to Middle East respiratory syndrome coronavirus (MERS-CoV) when used in seroepidemiological studies in animals. Genetically diverse MERS-CoV appear antigenically similar in MN tests. We confirm that MERS-CoV was circulating in dromedaries in Saudi Arabia in 1993. Preliminary data suggest that feral Australian dromedaries may be free of MERS-CoV but larger confirmatory studies are needed.


Assuntos
Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Camelus/sangue , Infecções por Coronavirus/epidemiologia , Coronavirus/imunologia , Testes de Neutralização/métodos , Infecções Respiratórias/epidemiologia , Animais , Austrália/epidemiologia , Bovinos/sangue , Coronavirus/isolamento & purificação , Infecções por Coronavirus/sangue , Infecções por Coronavirus/virologia , Humanos , Imunoglobulina G/sangue , Prevalência , Infecções Respiratórias/sangue , Infecções Respiratórias/virologia , Arábia Saudita/epidemiologia , Estudos Soroepidemiológicos
7.
Euro Surveill ; 18(36): pii=20574, 2013 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-24079378

RESUMO

We describe a novel spike pseudoparticle neutralisation assay (ppNT) for seroepidemiological studies on Middle East respiratory syndrome coronavirus (MERSCoV) and apply this assay together with conventional microneutralisation (MN) tests to investigate 1,343 human and 625 animal sera. The sera were collected in Egypt as a region adjacent to areas where MERS has been described, and in Hong Kong, China as a control region. Sera from dromedary camels had a high prevalence of antibody reactive to MERS-CoV by MERS NT (93.6%) and MERS ppNT (98.2%) assay. The antibody titres ranged up to 1,280 and higher in MN assays and 10,240 and higher in ppNT assays. No other investigated species had any antibody reactivity to MERS-CoV. While seropositivity does not exclude the possibility of infection with a closely related virus, our data highlight the need to attempt detection of MERSCoV or related coronaviruses in dromedary camels. The data show excellent correlation between the conventional MN assay and the novel ppNT assay. The newly developed ppNT assay does not require Biosafety Level 3 containment and is thus a relatively high-throughput assay, well suited for large-scale seroepidemiology studies which are needed to better understand the ecology and epidemiology of MERS-CoV.


Assuntos
Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Camelus/sangue , Infecções por Coronavirus/epidemiologia , Coronavirus/imunologia , Infecções Respiratórias/epidemiologia , Adolescente , Adulto , Idoso , Animais , Búfalos/sangue , Estudos de Casos e Controles , Bovinos/sangue , Criança , Pré-Escolar , Coronavirus/isolamento & purificação , Infecções por Coronavirus/sangue , Infecções por Coronavirus/virologia , Egito/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Infecções Respiratórias/sangue , Infecções Respiratórias/virologia , Estudos Soroepidemiológicos , Adulto Jovem
8.
Poult Sci ; 92(1): 114-8, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23243237

RESUMO

After emerging in Egypt in 2006, highly pathogenic avian influenza H5N1 viruses continued to cause outbreaks in Egyptian poultry and sporadic human infections. The strategy used by Egyptian authorities relied on vaccinating poultry, depopulating infected areas, and increasing awareness and biosecurity levels. Despite those efforts, H5N1 became endemic, and vaccine-escape variants are thought to have emerged even though commercial poultry vaccines were protective in laboratory settings. We studied the cross-reactivity of 6 commercially available H5 poultry vaccines against recent H5N1 Egyptian isolates in a field setting in Egypt. Only one vaccine based on an Egyptian H5N1 virus induced high cross-reactive antibody titers. Our results may be explained by the fact that the seed viruses in these vaccines are genetically distinct from H5N1 viruses currently circulating in Egypt. In light of our findings, we recommend that the H5N1 prevention and control strategy in Egypt be updated and reinforced. Special consideration should be given to the vaccination strategy, and the use of vaccines based on currently circulating viruses is advisable.


Assuntos
Anticorpos Antivirais/imunologia , Galinhas , Virus da Influenza A Subtipo H5N1/imunologia , Vacinas contra Influenza/imunologia , Influenza Aviária/prevenção & controle , Animais , Egito/epidemiologia , Vacinas contra Influenza/classificação , Influenza Aviária/epidemiologia
9.
Zoonoses Public Health ; 57(4): 265-72, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19486492

RESUMO

The threat of an influenza pandemic is looming, with new cases of sporadic avian influenza infections in man frequently reported. Exposure to diseased poultry is a leading risk factor for these infections. In this study, we used logistic regression to investigate serological evidence of previous infection with avian influenza subtypes H4, H5, H6, H7, H8, H9, H10, and H11 among 95 adults occupationally exposed to turkeys in the US Midwest and 82 unexposed controls. Our results indicate that farmers practising backyard, organic or free-ranging turkey production methods are at an increased risk of infection with avian influenza. Among these farmers, the adjusted odds ratios (ORs) for elevated microneutralization assay titres against avian H4, H5, H6, H9, and H10 influenza strains ranged between 3.9 (95% CI 1.2-12.8) and 15.3 (95% CI 2.0-115.2) when compared to non-exposed controls. The measured ORs were adjusted for antibody titres against human influenza viruses and other exposure variables. These data suggest that sometime in their lives, the workers had been exposed to low pathogenicity avian influenza viruses. These findings support calls for inclusion of agricultural workers in priority groups in pandemic influenza preparedness efforts. These data further support increasing surveillance and other preparedness efforts to include not only confinement poultry facilities, but more importantly, also small scale farms.


Assuntos
Vírus da Influenza A/classificação , Influenza Aviária/transmissão , Influenza Humana/transmissão , Perus , Zoonoses/transmissão , Matadouros , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Agricultura , Animais , Estudos Transversais , Feminino , Humanos , Influenza Aviária/epidemiologia , Influenza Aviária/virologia , Influenza Humana/epidemiologia , Influenza Humana/virologia , Masculino , Pessoa de Meia-Idade , Exposição Ocupacional , Fatores de Risco , Estados Unidos/epidemiologia , Adulto Jovem
10.
Poult Sci ; 88(4): 880-4, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19276439

RESUMO

Recent research has shown that poultry and swine workers, especially those with intense exposures, are at increased risk of zoonotic influenza virus infections. In multiple studies, US poultry workers and poultry veterinarians have evidence of previous infections with avian influenza virus. Similarly, US swine workers have strong evidence of previous and acute infections with swine influenza viruses. Mathematical modeling has demonstrated that such workers may accelerate the spread of pandemic viruses in their rural communities. Because these workers may contribute to the novel generation of viruses and serve as a bridging population in the cross-species sharing of influenza viruses, it seems prudent to include poultry and swine workers in influenza preparedness programs. Possible preventive and control interventions include special education programs to increase workers' use of personal protective equipment such as gloves, increased surveillance for influenza viruses among workers and their animals, recommendations that workers seek medical attention should they develop influenza-like illness, and workers' priority receipt of annual and pandemic influenza vaccines.


Assuntos
Surtos de Doenças/prevenção & controle , Influenza Aviária/transmissão , Influenza Humana/prevenção & controle , Exposição Ocupacional/prevenção & controle , Infecções por Paramyxoviridae/veterinária , Animais , Defesa Civil , Humanos , Vírus da Influenza A , Infecções por Paramyxoviridae/transmissão , Aves Domésticas , Fatores de Risco , Suínos , Estados Unidos/epidemiologia
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