Bird Flu Found at Three More Ostrich Farms

SOUTH AFRICA - Evidence of the bird flu virus has been   

 found at three further ostrich farms in the Western Cape.

The veterinary authority sent Follow Up Report No. 7 dated 22 September to the World Organisation for Animal Health (OIE).

Surveillance has revealed evidence of the bird flu virus – H5 and H6 sub-types – at three further ostrich farms in Western Cape, the same province where previous outbreaks occurred.

According to the report, all three premises were commercial ostrich farms. Farms tested positive on serology during routine surveillance but tested negative on PCR and no virus could be found. Diagnosis only confirmed after several follow-up PCR tests. South Africa only reports outbreaks on confirmation on PCR tests. Initially no clinical signs or mortalities were seen.

Stamping out in positive farms is taking place.

Poultry Vaccination as a strategy for controlling AI in commercial birds

Outbreaks of avian influenza in the poultry industry cause devastating economic losses and is generally controlled through extensive culling of infected birds. Alternative strategies also use vaccination as a supplementary control measure during avian influenza outbreaks.

Advantages of Vaccination

• Vaccination reduces susceptibility to infection.
• A higher dose of virus is necessary to infect the vaccinated birds.
• Vaccinated birds shed less virus.
  - Decreased contamination of the environment.
  - Decreased risk of human infection
• Used strategically vaccination compliments a stamping out strategy by slowing/stopping the spread of the virus