The USDA evaluated the efficacy of current vaccine options for HPAI in addition to economic impacts of vaccination and decided that, as it currently stands, additional criteria must be met before a vaccine can be approved for emergency use.

Before a vaccine is approved, the USDA also said it wants to be sure that the vaccine industry is in a position to produce enough doses to create an effective control measure. Finally, additional outreach with trading partners will be required to avoid significant market disruptions.

USDA will continue to encourage development of vaccines for HPAI and will approve vaccines as they are developed and evaluated.

The vaccine currently available offers just 60 per cent effectiveness in chickens, leaving 4 in 10 birds unprotected. The vaccine’s effectiveness in turkeys is still being studied.

The US is still trading poultry products in open markets with countries that account for approximately 84 per cent of the value of US eggs and poultry exports in 2014.

However, the USDA said some significant trading partners have indicated that, if we began vaccinating, they would ban all poultry and eggs imports from the US until they could complete a risk assessment. Risk assessments are a common method of evaluating these types of requests, and often require a significant amount of time.

The loss of these markets could potentially cost US poultry producers billions in lost export sales that would need to be diverted to other export and domestic markets, with no clear timeline for reopening closed markets. The USDA will continue to work closely with stakeholders and trading partners throughout the response.

USDA’s Animal and Plant Health Inspection Service (APHIS) will reevaluate its vaccination decision as more effective vaccines are developed and ready for use, carefully considering both the efficacy of the vaccine and the potential trade impacts.

If used, vaccines will be targeted in the states and poultry sectors where they can be most effective. Areas where quarantine, depopulation, and enhanced biosecurity cannot stop the spread of HPAI would be prioritised.

In the weeks and months ahead, the USDA said will continue to support efforts to develop a more effective vaccine, assist poultry producers with strong biosecurity measures, indemnify producers for losses, and take aggressive action to maintain open markets for US poultry based on international standards.