The largest outbreak of bird flu in American history was an H5N2 virus, which led to the deaths of 17 million domestic birds and cost the nation more than $400 million during an outbreak in Pennsylvania that started in 1983.

The emergence and spread of virulent strains of avian influenza has been attributed by experts to the intensely overcrowded, unsanitary, and stressful conditions that often characterize large-scale factory farming in industrialized agriculture.

In nature, disease-causing strains of avian influenza rarely spread far because the birds sicken and die before they can fly to spread it to others.

Michael Greger Quotes