AVIAN INFLUENZA (= CHICKEN
FLAVOR)
Avian Influenza (AI), it is an international problem.
Situated in the list is A disease in the OIE.
Factor
Orthomyxoviridae, Influenza A virus
Influenza viruses are divided into three groups A, B and C.
Group A includes factors responsible for the disease in the wing
AI viruses
low pathogenic viruses (LPAI) mid-pathogenic viruses (the MPAA) high pathogenic viruses (HPAI)
Typing of AI viruses
Hemagglutinin antigen (HA: 1-15) Neuraminidase antigen (NA; 1-9)
Epidemiology
First described in chickens in Italy in 1878
The first isolation in the hindi was made in North America in 1963
Information on the ecology of poultry influenza viruses has been well understood since the 1970s
Pathogenicity
H5 and H7 subtypes have been effective in serious epidemics that have been seen to date.
Pennsylvania-Virginia-New Jersey (1983-84) H5N2 Italy (1999-2002) H7N1
Holland-Belgium (2002- ) H7N7
The pathogenicity of AI virus strains is widely distributed There is a high frequency of antigenic change between AI viruses
The isolation of HPAI viruses from outbreaks seen in different countries in chickens is not very intense and usually LPAI viruses are isolated
Host distribution
Poultry, human, horse, pig, seal, whale, mink Between the wings;
turkey, chicken, duck-goose, quail, ostrich
pheasant, lamb chick, seagull, partridge, sea birds, marsh birds
budgerigar, peacock, parrot
Spread of virus and sources of contamination
Migratory water birds are defined as virus
reserves.
Infection
Direct contact with disease-affected water birds (open-fed wings)
Infected wings Base
Movement of contaminant equipment between poultry People in contact with contaminant material and infected poultry (especially with fertilizer)
Live poultry markets
Usually AI birds will spread the virus around for two weeks and the virus will not usually be detected after 4 weeks.
The susceptibility of the agent to chemical substances
Oil solvents (detergents) Formalin
Beta-propiolactone Oxidising agents acids
ether
Sodium desoxycholate SDS
Ammonium salts
Resistance to physical conditions
The virus stays alive for long periods, especially in cold and humid environments (about 105 days)
30-35 days at 4 ° C and 7 days at 20 ° C
In environmental environments, viruses can be isolated from lakes and ponds, especially where water birds are present, and protect the causative infectivity for a certain period of migration
In humans AI
In humans, until 1997 H1, H2, H3
After this year (Hong Kong, 1997) H5N1 Finally, H9N2 infection has been reported
Diagnosis
The incubation period can range from a few hours to 3 days and up to 14 days individually
Morbitide high
Mortality can range from negligible to 100%
Clinical findings are highly variable
from subclinic to mild respiratory tract infections and multiply acute generalized form
In some cases, the disease is so rapid that death can occur without any clinical symptoms
Severe depression, diminished activity, decreased feed intake, attenuation
Congregation at puberty, head and neck edema, hairless cyanosis
Respiratory system indications: cough, sneeze, nasal discharge, respiratory sounds, excessive lacrimation, Neurological manifestations
Decrease in egg production Diarrhea
Macroscopic findings
In sinus, catarrhal, fibrinous, serofibrinous, mucopurulent, or caseous inflammation is observed
Exercise ranging from serous to treacherous
The airways are thickened and fibrinous and caseinous exudate.
peritonitis
Especially in the populations of the colon and / or intestine with catharral / fibrinous enteritis
Oviduct exudate
In the case of HPAI virus infections, any macroscopic finding may not develop due to sudden death.
Commonly seen lesions,
The sympathies are swollen and edematous head, zionitic, hemorrhagic beards and twigs
Congestion and haemorrhage can also be seen in stools As the disease progresses, necrotic foci are frequently
encountered in internal organs (liver, spleen, kidney and lung).
Isolation and identification
Materiel
Dead or live wings Viscera
Cloacal and / or trecheal swabs
Swabs in sterile transport fluid containing antibiotics Organs are shipped in sterile plastic tubes or bags.
Organs of the digestive system and other organs should be sent separately.
The receiving organs should be delivered to the laboratory at 4 C within 48 hours.
Virus isolation
Embryo hen egg (All strains are found in ETY 9-11 days) DK (CEF, MDCK)
Inoculation to the experimental animal (Chicken, turkey, duck)
Virus identification
HA
HI (Type A NP, MP diagnosis)
(HA, NA; identification of subtypes)
Pathogenicity tests (IVPI)
Serology
Detection of presence of antibodies should be done at earliest 7-10 days
AGP
ELISA VN
