Thank goodness* I’m so glad that we got the pneumonia shots too 2x!
Orent cites geneticists who believe that the 1918 flu evolved in wild birds, not domestic fowl. In general, wild migratory birds tend to spread milder forms of influenza because the severe infections ground them before they can spread the virus too widely. According to Orent, it was just historical fluke that the the 1918 virus managed to spread from wild birds to humans. She speculates that if hundreds of thousands of people hadn’t been crammed into the barracks, trenches, and transporter ships of WWI, the 1918 flu pandemic might never have gotten off the ground.
Revere the epidemiologist at Effect Measure critically examines Orent’s hypotheses and finds them thoroughly unconvincing. Revere challenges Orent’s assumption that a devastating pandemic flu would have to be both rapidly lethal and highly transmissible. Even in 1918, the fatality rate was “only” 2%–but 2% of a huge number of infected people. Furthermore, creatures infected with the flu are contagious before they’re symptomatic. So, infected migratory birds may spread the disease across long distances before they are overcome.
Revere makes a number of other interesting points against Orent, but I’ll leave off here and encourage you to read the whole thing.