Falklands : Chief Vet Writes About Bird Flu
Submitted by Falkland Islands News Network (Juanita Brock) 24.10.2005 (Article Archived on 07.11.2005)
Steve Pointing tells readers about the bird flu epidemic.
AVIAN INFLUENZA – BIRD FLU
By Steve Pointing: Wool Press
Definition
Avian Influenza is a highly contagious viral disease affecting the respiratory, digestive and/or nervous system of any species of birds. It is caused by a Type “A” influenza virus. There are two types of avian influenza virus, low pathogenicity (LAPI) or high pathogenicity (HPAI). The last outbreak of avian influenza in Great Britain was in 1991. The most recent outbreak close to the Falkland Islands was in Chile in June 2002 where there were two outbreaks in the central part of Chile, leading to the death or slaughter of about one million birds.
History and Spread of the Disease
A highly pathogenic form of avian influenza was known as “fowl plague.” It first appeared in Italy more than 100 years ago (around 1878). Pathogenic avian influenza was first recognised in the United States in 1924/25. Pathogenic and mildly pathogenic influenza “A” viruses occur worldwide. Highly pathogenic avian influenza “A” (HPAI) viruses of the “H5 and H7” subtypes have been isolated occasionally from free living birds in Europe and elsewhere. The most recent outbreaks of the disease occurred in Australia, Pakistan, Hong Kong, Italy, Chile and Mexico. A serious of “A1” in the Netherlands in 2003, spreading to Belgium and Germany, affected some 250 farms and necessitated the slaughter of more than 28 million poultry.
Another serious epidemic of the disease affected Japan, South Korea, and Southeast Asia early in 2004. This outbreak is still going on in China and Southeast Asia. There is evidence that “H5” viruses of low pathogenicity may mutate and become highly pathogenic.
Clinical Signs
Typically the disease presents suddenly with affected birds showing oedema (swelling) of the head, cyanosis of the comb and wattles, dullness of appetite, respiratory distress, diarrhoea and drop on egg production. Birds may die without any sign of disease being apparent.
Transmission
- Direct contact with secretions from infected birds, especially faeces
- Contaminated feed, water, equipment and clothing
- Clinically normal waterfowl and seabirds may introduce the virus into flocks
- Broken, contaminated eggs may infect chicks in the incubator
Treatment
*No Treatment*
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