From Pale Rider: The Spanish Flu of 1918 and How It Changed the World, by Laura Spinney (PublicAffairs, 2017), Kindle pp. 93-94:
Australia saw the epidemic coming from a long way off, both in time and space. Its authorities first heard about a flu epidemic in Europe in the northern hemisphere summer of 1918, and in September they became aware of the horrifying reports of the lethal second wave. Having watched it advance through Africa and Asia, they finally introduced quarantine procedures at all Australian ports on 18 October (New Zealand did not follow suit). When jubilant crowds gathered in Sydney’s Martin Place to celebrate the armistice in November, therefore, they enjoyed the privilege–almost unique in the world–of having nothing to fear from the virus. Though the country did receive the third wave in early 1919, its losses would have been far greater had it let the autumn wave in.
The Philippines were not protected by their island status. When flu broke out there, it didn’t occur to the occupying Americans that it might have come from outside, even though the first casualties were longshoremen toiling in the ports of Manila. They assumed its origins were indigenous–they called it by the local name for flu, trancazo–and made no attempt to protect the local population, which numbered 10 million. The only exception was the camp on the outskirts of Manila where Filipinos were being trained to join the US war effort, around which they created a quarantine zone. In some remote parts of the archipelago, 95 per cent of communities fell ill during the epidemic, and 80,000 Filipinos died.
The starkly contrasting fates of American and Western Samoa–two neighbouring groups of islands in the South Pacific–show what happened when the authorities got the direction of travel right, and when they got it wrong. The American authorities who occupied American Samoa realised not only that the threat came from outside the territory, but also that indigenous Samoans were more vulnerable to the disease than white-skinned settlers, due to their history of isolation, and they deployed strict quarantine measures to keep it out. American Samoa got off scot-free, but Western Samoa, under the control of New Zealand, was not so lucky. After infection reached the islands via a steamer out of Auckland, local authorities made the same error as the occupiers of the Philippines, and assumed that it was of indigenous origin. One in four Western Samoans died in the ensuing tragedy which, as we’ll see, would dramatically shape the islands’ future.