RESUMO
Highly pathogenic avian influenza (HPAI) subtype H7N8 was detected in commercial turkeys in January 2016. Control zone surveillance discovered a progenitor low pathogenic avian influenza (LPAI) virus in surrounding turkey flocks. Data analysis supports a single LPAI virus introduction followed by spontaneous mutation to HPAI on a single premises.
RESUMO
Surveillance for influenza A viruses in wild birds has increased substantially as part of efforts to control the global movement of highly pathogenic avian influenza A (H5N1) virus. Studies conducted in Egypt from 2003 to 2007 to monitor birds for H5N1 identified multiple subtypes of low pathogenicity avian influenza A viruses isolated primarily from migratory waterfowl collected in the Nile Delta. Phylogenetic analysis of 28 viral genomes was performed to estimate their nearest ancestors and identify possible reassortants. Migratory flyway patterns were included in the analysis to assess gene flow between overlapping flyways. Overall, the viruses were most closely related to Eurasian, African and/or Central Asian lineage low pathogenicity viruses and belonged to 15 different subtypes. A subset of the internal genes seemed to originate from specific flyways (Black Sea-Mediterranean, East African-West Asian). The remaining genes were derived from a mixture of viruses broadly distributed across as many as 4 different flyways suggesting the importance of the Nile Delta for virus dispersal. Molecular clock date estimates suggested that the time to the nearest common ancestor of all viruses analyzed ranged from 5 to 10 years, indicating frequent genetic exchange with viruses sampled elsewhere. The intersection of multiple migratory bird flyways and the resulting diversity of influenza virus gene lineages in the Nile Delta create conditions favoring reassortment, as evident from the gene constellations identified by this study. In conclusion, we present for the first time a comprehensive phylogenetic analysis of full genome sequences from low pathogenic avian influenza viruses circulating in Egypt, underscoring the significance of the region for viral reassortment and the potential emergence of novel avian influenza A viruses, as well as representing a highly diverse influenza A virus gene pool that merits continued monitoring.
Assuntos
Animais Selvagens/virologia , Aves/virologia , Vírus da Influenza A/patogenicidade , Influenza Aviária/virologia , Filogenia , Sequência de Aminoácidos , Migração Animal , Animais , Teorema de Bayes , Galinhas , Egito/epidemiologia , Genes Virais/genética , Glicoproteínas de Hemaglutininação de Vírus da Influenza/química , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Vírus da Influenza A/genética , Influenza Aviária/epidemiologia , Neuraminidase/química , Neuraminidase/genética , Reação em Cadeia da Polimerase , Vigilância da PopulaçãoRESUMO
In response to an outbreak of Crimean-Congo hemorrhagic fever in western Afghanistan, we measured immunoglobulin G seroprevalence among household members and their animals. Seroprevalence was 11.2% and 75.0% in humans (n = 330) and livestock (n = 132), respectively. Persons with frequent exposure to cattle had an elevated risk of being immunoglobulin G positive.
Assuntos
Surtos de Doenças , Vírus da Febre Hemorrágica da Crimeia-Congo/imunologia , Febre Hemorrágica da Crimeia/epidemiologia , Afeganistão/epidemiologia , Animais , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Bovinos , Febre Hemorrágica da Crimeia/diagnóstico , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Prevalência , Fatores de Risco , Ovinos/virologiaRESUMO
From February through April 2007, avian influenza (H5N1) was confirmed in poultry in 4 of 34 Afghan provinces. A survey conducted in 2 affected and 3 unaffected provinces found that greater knowledge about reducing exposure was associated with higher socioeconomic status, residence in affected provinces, and not owning backyard poultry.
Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Virus da Influenza A Subtipo H5N1 , Influenza Aviária/prevenção & controle , Adolescente , Adulto , Afeganistão/epidemiologia , Animais , Galinhas , Coleta de Dados , Feminino , Humanos , Influenza Aviária/virologia , Masculino , Pessoa de Meia-Idade , Fatores SocioeconômicosRESUMO
The 5 Department of Defense (DoD) overseas laboratories conduct research on a vast array of infectious diseases. This commentary focuses on the role of the Naval Medical Research Unit No. 3 (NAMRU-3, Cairo, Egypt) in influenza surveillance and research, with emphasis on the role of the comparative medicine (US Army military occupational specialty 64E) veterinarian assigned there. Every year, tens of thousands of members of the US Armed Forces are vaccinated for so-called "seasonal influenza." The vaccine used is reformulated annually, based on antigenic characterization of viral isolates generated through global surveillance. NAMRU-3 contributes to this global surveillance for the Eastern Mediterranean region. The emergence of H5N1 Highly-pathogenic Avian Influenza (HPAI) and concerns over its possible role in precipitating a pandemic have accentuated the role of veterinarians with field and laboratory diagnostics experience in this system.