The first outbreak of avian influenza this season on a farm in France has put the industry on watch to see if the country's strategy of vaccinating birds will prove effective, helping avoid a repeat of previous crises that killed millions of poultry, reported Reuters. 

The farm ministry said on Tuesday a first case of the highly pathogenic avian influenza was found among turkeys in Brittany, northwestern France, as a seasonal wave of infections spreads across Europe, the United States and Japan.

Avian influenza is usually carried by migrating wild birds before being transmitted between farms. It ravaged flocks around the globe in the past years, disrupting supply, fueling food prices and raising concerns over the risk of human transmission.

To protect itself, France launched a vaccination campaign in early October, initially limited to ducks, which can easily transmit the virus without showing symptoms.

"The new outbreaks are a stress because with these viruses one never knows if the 'dike' will be strong enough," Marie-Pierre Pe, director of France's duck and foie gras industry group CIFOG, told Reuters, referring to prevention measures.

France aims to vaccinate over 60 million ducks but only 70% have received a first shot and 40% been fully vaccinated so far, Pe said.

France is the first large exporter to vaccinate poultry against avian influenza, braving trade barriers from countries that fear the virus could spread without being noticed.

The vaccine is not supposed to fully protect birds from catching the disease but would limit its spread and thus avoid massive preventive culls. It comes in addition to standard biosecurity and control measures.

"Vaccination is an additional tool but it does not protect us completely," Philippe Gelin, chief executive of France's largest poultry group LDC, told Reuters. "We need to be vigilant and ensure that it remains limited."