The last time a major pandemic swept through the islands — a century ago — more than 2,300 people in Hawaii died from what was called the Spanish flu.

Health officials initially downplayed the severity of the crisis, but before it was over, hospitals were overrun, makeshift medical facilities were set up and businesses temporarily shuttered as Hawaii struggled with the outbreak.

Largely forgotten today, the 1918 Spanish flu pandemic was the fourth most fatal epidemic in the historical record of Hawaii, according to a 1999 paper in the Hawaiian Journal of History.

Written by former state Statistician Robert C. Schmitt and Eleanor C. Nordyke, a population expert formerly at the East-West Center, the paper recounts the health crisis that gripped the then-U.S. territory during World War I and through the first half of 1920.

The U.S. Centers for Disease Control and Prevention estimates that more than 50 million died in the worldwide influenza pandemic, including some 675,000 Americans.

Overcrowding and global troop movements during the war helped push the 1918 flu across the globe, the CDC says, and the lack of vaccines and treatments created a major public health emergency.

From the Spanish flu, health officials learned that social distancing and shutting down events and gathering places are effective measures to battle a dangerous respiratory virus.

In Hawaii the first cases of the Spanish flu, also known as “la grippe,” showed up on Oahu in the island’s military and naval bases at the end of June 1918, according to the paper.

A headline in the Honolulu Star-Bulletin on July 1 announced “600 Soldiers at Schofield Down With La Grippe.” The story went on to say that more than 1,200 soldiers, sailors and civilians were victims, and enough pineapple workers called in sick to make it necessary to call on children to help with the work.

A couple of days later a story announced that “Honolulu Likely to Be Victim of Grippe Epidemic.” A Fort Shafter physician was quoted as saying that civilian doctors were already reporting cases and that the problem was only going to grow worse.

“There is little enough one can do in the nature of preventive treatment,” the doctor added. “Keep away from ‘grippees’ as much as possible and rinse the mouth and nostrils with germ-destroying lotions as often as possible. Otherwise it’s largely a question of luck.”

The first wave of the 1918 pandemic, blamed on shipping from Japanese and Chinese ports, quickly swept across Oahu, lasting for a couple of months, followed by a second wave in December and January.

Public officials appeared unimpressed. As late as October 1918, the chief quarantine officer of the U.S. Public Health Service in Honolulu was still saying there was “no reason to feel alarmed over the influenza situation” and doubting there was “such a thing as a real epidemic.”

Associate professor Shana Brown, History Department chairwoman at the University of Hawaii at Manoa, said there were strict press controls during World War I, and that led to a dearth of public information about the pandemic.

The territorial sanitarian in the fall of 1918 denied the existence of an epidemic, and officials declared weeks later that influenza had been “virtually stamped out” and that it was unlikely to recur.

“Later on you really couldn’t hide it anymore,” said Brown, who is teaching a course on the history of human disease and recently completed a unit on the 1918 epidemic and its impact on Hawaii.

Eventually, the waves of disease exposed shortages of physicians, hospital beds, nurses and other medical personnel and facilities.

Newspapers reported in January 1919 that Queen’s Hospital was transformed into a general hospital for influenza cases, the authors wrote.

Health officials pleaded for help from the U.S. Army Medical Department, but it was already slammed by its own heavy caseloads.

Pa Ola Day Camp of Palama Settlement, with 18 beds, and smaller outposts on Sand Island and at the Lihue Armory were used as emergency hospitals for influenza cases.

A women’s committee was assembled to inspect schools and distribute medicine to pupils with colds, while former nurses were recruited to inspect schools for flu cases.

By this time many mainland communities had shut down schools, theaters and churches as public health measures, and local health officials were urged to do the same. They mostly resisted, however, arguing that it had little or no effect on death rates, according to the paper.

Eventually, some businesses and institutions temporarily closed, and indoor public gatherings, including church services, were prohibited. While public schools remained open, several private schools — Kameha- meha, St. Andrew’s Priory and Saint Louis among them — closed for varying periods. Most theaters reopened in February 1919.

Brown said Oahu suffered from an inconsistent, patchwork response of closings and openings throughout the pandemic.

Additionally, the crisis struck during a period of serious labor unrest that ended with the sugar strike of 1920. Management ended up evicting 12,000 strikers from plantation housing, and about half of them moved to Honolulu, where scores of strikers and their families died from the disease, the report said.

On the mainland, deaths from flu-related causes spiked in 1918, then dropped off the following year. By contrast, Hawaii peaked in 1920, with the reasons for the lag unclear, according to the authors.

But death rates in peak years are quite comparable. The country as a whole experienced civilian mortality of 562 per 100,000 in 1918, while Hawaii’s peak year in 1920 reached 571 per 100,000.

In Hawaii the average annual death rates for influ- enza-related disease during the pandemic were highest for children under 5 years of age and those 60 and over. It was lowest for those between 5 and 19.

By race, flu deaths were “exceptionally high for pure Hawaiians, less so for Filipinos, and lowest for Caucasians. Male and female rates differed but little. By counties, Kauai reported the highest rate, followed by Oahu, Maui, and the Big Island.”

“Why the influenza death rate followed such a distinct geographic pattern, dropping regularly from west to east, is an unanswered question,” authors Schmitt and Nordyke wrote.

In Hawaii, more than 2,338 people died from influenza and related causes between July 1, 1918, and June 30, 1920. But the death toll likely was considerably higher because the total didn’t include mortality among military personnel during the war.

Brown, the UH history professor, said the Spanish flu epidemic proved the world had become a smaller place and that Hawaii was not protected anymore by its geographical isolation.

It also demonstrated the importance of public knowledge and the dissemination of good information in dealing with an infectious disease.

“If there isn’t an informed public, people can’t make good decisions for themselves and their community,” Brown said.