The 1918 influenza pandemic hit almost every country on Earth, Gregory Cochran explains:
It missed American Samoa entirely, which is interesting. It’s even more interesting when you notice that it hit the neighboring islands of West Samoa harder than anywhere else.
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American Samoa was physically quite close to Western Samoa, less than 100km. There were close cultural ties: people intermarried and often sailed back and forth. But the governmental structure was different. There were no copra plantations in American Samoa, so you didn’t have any powerful business interests lobbying for suicide. The US Navy ran the colony. John Martin Poyer, an officer that had retired from active duty due to illness, was brought back to active duty in 1915 to serve as Governor of American Samoa.
Both American Samoa and West Samoa had advance warning of the flu’s danger: they both had wireless sets and occasional mail.
Washington didn’t micro-manage American Samoa, not being all that interested. A policy of benign neglect was interpreted by Poyer as an opportunity to act on his best judgment, in the finest traditions of the US Navy. He imposed quarantine. That was harder that it sounds, because of the frequent family visits between West Samoa and American Samoa — but Poyer also had the support of the local chiefs, who understood how serious imported epidemics could be. The people of American Samoa self-blockaded, on top of official quarantine: they sent out canoes to stop any and all visitors. They never had a single case.
But that could never work today because reasons. And because Shut Up.