German health officials were quick to react when the deadly H5N1 bird flu virus was discovered at a farm in the south of the country: 160,000 geese have been slaughtered and the area is now quarantined.

Authorities discovered the H5N1 bird flu virus late last week at a poultry farm in Wachenroth, Bavaria, near the city of Erlangen. Four hundred birds had been found dead there. The lethal strain was found in five birds.

Officials announced Friday that measures would be taken immediately: 160,000 geese would be slaughtered, while the farm would be isolated. Erlangen is about 200 kilometers north of Munich.

Sunday, the birds were sacrificed, in Germany’s vastest culling operation ever. A team of eight veterinarians and numerous poultry workers was necessary to complete the activity.

German health officials are still investigating the source of infection. Previous reports suggested the infected animals came from another poultry farm in the northern state of Lower Saxony.

This has not been confirmed and Bavarian Health Secretary Otmar Bernhard has stated the origin of the outbreak has not been categorically identified yet.

There have been previous cases of the deadly H5N1 strain in Bavaria and other regions, but only in wild birds. These were discovered in June and July.

The H5N1 strain of avian influenza has been particularly ravaging in Asia. Of the 200 people to have lost their lives to the virus over the past several years, the vast majority have been from Asia.

No victims have been reported in Europe, though there have been outbreaks, in Germany, the Czech Republic, Hungary etc.

It is still difficult for humans to become infected, especially if they follow basic hygienic recommendations (the most preached being, “avoid contact with dead birds”). Scientists nevertheless fear a potential mutation of the H5N1 virus into a form easily transmitted among human beings.