Type A influenza virus is the cause of avian influenza, characterized by haemagglutinin and neuraminidase antigens on its surface. It is transmitted through aerosol inhalation, contact with infected birds, or fomites. Clinical signs include sudden death, respiratory signs, nervous signs, and decreased egg production. Pathology shows anaemia, cyanosis, and ecchymotic discolouration of shanks and feet. Prevention relies on biosecurity measures, stamping out infected flocks, and disease surveillance. The first outbreak in Nigeria was diagnosed in 2006 in Kaduna State and others were reported in 2007 in Anambra and Lagos States.

1. By
Wanze Enyi Nwosu, DVM (A.B.U.)

2. The Disease

3. Aetiology
Type A Influenza Virus belonging to the family Orthomyxoviridae.
characterized by haemagglutinin
(HA) and neuraminidase (N) antigens occurring on the surface of the virus

4. Epidemiology
Source, transmission, distribution, incidence

5. Mode of transmission
 Aerosol inhalation
 Contact with infected birds
 fomites

6. Clinical Signs
 Sudden death
 Acute decline in egg production
 Respiratory signs
 Nervous signs

7. Pathology

8. Path cont’d...
Anaemic, cyanotic
comb Healthy comb

9. Ecchymotic discolouration of
shanks and feet
Others are:
•Tracheitis
•Pulmonary
oedema
•Airsacculitis

10. Treatment
 Theoretically possible to stay viral effect with
antiviral agents, however, this is against the
current standard practice

11. Prevention and Control
Prevention Control
 Biosecurity measures  Institution of perimeter
 Stamping out
 Clean up +
disinfection
 Payment of
compensation
 Sensitization
campaigns
 Disease surveillance

12. Avian influenza in man
Respiratory signs, fever, death

13. Avian Influenza in Nigeria
•1st diagnosed Tue 10 Jan 06
and confirmed Wed 08 Feb
06 in Kaduna State
•Outbreak recorded in
Nsugbe, Anambra State on
Sat 06 Oct 07
•1 human case reported on
17th Feb 2007 in Lagos State
•Public panic engendered by
media hysteria
•Potential for new global
cycle in Nigeria-------via
Hadejia-Nguru wetland in
Yobe State

14. Thank you for listening