State and federal officials have said they have eradicated the avian virus Exotic Newcastle disease from southern California and have therefore lifted any remaining quarantine restrictions on poultry shipments.

“We’re confident that we’re free,” Paul Ugstadt, a US department of agriculture veterinarian for California and Nevada, was quoted by the Los Angeles Times as saying. “We’ve done enough testing in the quarantined area to make sure that we’re free.”

Although not thought to be harmful to humans, the flu-like virus is highly contagious among birds and is often fatal to them.

This particular outbreak began last autumn and had spread to commercial poultry operations in southern California by winter. Quarantine restriction were placed on eight counties and more than three million birds were destroyed in a bid to control the outbreak.

The federal government spent US$160m to combat the outbreak in California, including compensation for poultry farmers whose birds were destroyed.

No California birds have been found to have the virus since May, the paper reported.