Infectious bursal disease virus (IBDV)

Biosecurity New Zealand is responding to a potential detection of the type 1 strain of Infectious Bursal Disease Virus (IBDV-1) at the Mainland Poultry farm in Waikouaiti, Otago – a South Island egg farm.


  • Preliminary test results indicate the virus is likely present on the Mainland Poultry property but further testing overseas is required to confirm this. Those results are expected around mid-September. 
  • There is no food safety risk with this virus and people should have no concern eating chicken meat or eggs. There will be no impact on domestic egg and chicken meat supply.
  • No birds at the Mainland Poultry farm in Waikouaiti have disease symptoms and the farm itself is under voluntary biosecurity controls as a precautionary measure. 
  • There are two different types of IBDV – Types 1 and 2. Type 2 is already in New Zealand and causes no significant health issues in the national flock and is of no trade concern. The current suspect result is for Type 1.

Background situation to IBDV discovery

Testing by the egg and poultry industries and Biosecurity New Zealand found a possible detection of type 1 of a chicken virus - Infectious Bursal Disease (IBDV-1) - in layer hens at a South Island egg farm.

Preliminary test results indicate the disease may be present at the Mainland Poultry farm Waikouaiti in Otago, through its own regular, voluntary testing routine.  No birds at the farm are showing any signs of sickness.

Biosecurity New Zealand is awaiting further test results from overseas. They are expected around mid-September.

IBDV type 1 was discovered in New Zealand in 1993. An industry-led programme has meant New Zealand has been able to claim absence of the disease. Most other countries in the world have this virus and successfully manage it within the industry.

No food safety risk from the disease

IBDV is not a food safety issue. Chicken meat and eggs are safe to eat. Various types of IBDV, including the type 1 strain, are present in commercial flocks around the world and people continue to safely consume eggs and poultry meat and meat products.

How IBDV affects chickens

Infectious bursal disease virus affects the immune system and is seen in young chickens worldwide. Chickens are most susceptible to clinical disease at 3 to 6 weeks of age. IBDV is quite infectious, but the birds suspected to be infected on the affected farm aren't showing any disease symptoms.

What we're doing 

Biosecurity New Zealand is now working with the egg and poultry industries to understand, if confirmed as positive, the scale of the situation and what control or eradication measures are available.

There is no food safety risk with this virus and people should have no concern eating chicken meat or eggs. There will be no impact on domestic egg and chicken meat supply.

While Biosecurity New Zealand waits for final confirmation from the overseas laboratory, we will stop issuing certificates for the export of chicken products to countries that require a guarantee that we are IBDV type 1-free. This involves the trade in poultry meat and poultry products to 4 countries, with Australia being the largest importer of chicken meat.

Biosecurity New Zealand has been working closely with the affected farm to ensure all risks are managed while Biosecurity New Zealand and industry await confirmation.

Prevention and treatment of infectious bursal disease

There is no treatment for IBDV. However, support therapies such as vitamin and electrolyte supplements and antibiotics to treat any secondary bacterial infections, may reduce the impact of the disease.

Depopulation and rigorous disinfection of contaminated farms have achieved some limited success in preventing disease spread. Prevention is through good biosecurity and vaccination.

Industry organisations

Egg Producers Federation of New Zealand

Poultry Industry Association of New Zealand

Last reviewed: