Avian influenza

Avian influenza

Influenza (flu) viruses (AIV). AIV replicates frequentlly among birds in a form of low pathogenicity (LPAIV).

Wild birds worldwide are a reservoir of AIV and may carry the viruses in their intestines, but usually do not get sick. However, LPAIV of the subtypes H5 and H7 have the potential to mutate to highly pathogenic avian influenza viruses form (HPAIV) which are highly contagious for domestic birds and will make e.g chickens, ducks, and turkeys very sick and kill them. Infected birds shed influenza virus in their saliva, nasal secretions, and feces.

Avian influenza usually refers to influenza virus type A found chiefly in birds, but infections can occur in humans. The risk is generally low to most people, because this virus do not easily infect humans. However, confirmed cases of human infections (especially HPAIV H5N1 or H7N7, but also LPAIV of the subtypes H9, H7 and H5) have been reported. For HPAIV H5N1 more than 250 human deaths occurred since 1997, mainly in Asia and Egypt.

More information:

Information on Avian Influenza from CDC

OIE: Update on highly pathogenic Avian Influenza

Technical disease cards OIE

EPIZONE and avian influenza

Click here for the interview with Dr Ilaria Capua, Head of Virology Department at Instituto zooprofilattico Sperimentale delle Venezie in Italy, and is internationally recognised for her work on Avian influenza. Ilaria Capua is Work Package leader of EPIZONE Work Package 6.2, Field Epidemiology & Surveillance of AI and APMV

Diagnostics

  • Numerous activities for harmonization and standardization of real-time RT-PCR assays for AIV.
  • A list of validated, functional real-time RT-PCR assays useful for the sensitive, specific and robust detection of AI based on information of collected data has been compiled and summarized in a  review article.
  • Available information on DIVA diagnostics in HPAI was collected and published in a review article.
  • A unique pan viral DNA chip for virus discovery and subtyping and dedicated DNA chips for accurate subtyping of important epizootic viruses has been developed. In addition, a dedicated DNA chip is focused on Influenza subtyping (HA and NA) and pathotyping.
  • For Avian influenza an in-house ELISA system for the detection of antibodies specific to neuraminidases type 1, 2 or 3  (subtypes N1, N2 and N3) has been developed.
  • Pen-side tests based on strand displacement amplification methods, or commercial RT-LAMP kits for the detection of H5 and H7 influenza A virus have been evaluated.

Surveillance and Epidemiology

  • For avian influenza (AI) sequencing protocols of partner institutes were collated and distributed among partners for comparison. Sequencing data generated from the involved partners was integrated into the database GISAID (Global Initiative on Sharing Avian Influenza Data) that will be served and used by the international community beyond the EPIZONE network and also include stakeholders from related fields and that through the provided data will increase the insight into the epidemiology of AI.

Want to know more