Photo from the National Museum of Health & Medicine

What percentage of the American population got sick during this pandemic and how sick did they get?

Exact numbers can never be known because physicians were not ordered to report flu cases to the Public Health Services until September 27th, 1918, nearly a month into the outbreak, and overwhelmed physicians submitted incomplete paperwork or none at all. In rural areas where doctors were few the numbers are most imperfect. As in any epidemic, there were people who died uncounted, and cases of misdiagnosis.

Numbers of the worldwide death toll have been adjusted up several times, from a 1924 estimate of about 21.5 million to a 1991 estimate of as high as 39.3 million. A more recent study, “Updating the Accounts: Global Mortality of the 1918 - 1920 ‘Spanish’ Influenza Pandemic,” published in the Bulletin of Historical Medicine in 2002, raised the estimate again, this time to 50 million—with the caveat that number might be understating the true number by as much as 100%.

The 2002 study sets a death toll of 675,000 US deaths from a total population of 103,208,000 (1 in 152.9 Americans). In total, 25% - 28% of Americans got the flu during the pandemic, which lasted from September 1918 until April, 1919. The vast majority of cases—80%—were typical of the seasonal flu, lasting for a few days and causing the fever, prostration, and the familiar “beaten all over with a club” feeling that all flu sufferers have experienced. Approximately 20% developed pneumonia, and half of those died. Other fatalities were caused by streptococcus, while some died because their immune system was overwhelmed with the virus itself. Cyanosis, a condition in which oxygen deficiency from fluid-filled lungs caused patients to turn “as blue as huckleberries,” was a death sentence; most victims died within 24 - 48 hours.

• Pennsylvania was hit hard, with 24,000 dying the first month of the pandemic. On October 10th, 528 people died in Philadelphia, and convicts were ordered to dig graves to get the bodies out of an overflowing city morgue.
• In Tennessee, the pandemic began in September in Memphis and quickly spread to Nashville where 40,000 cases led to 468 dead. “The man who dug his neighbor’s grave today might head the funeral procession next week,” one physician wrote in his diary.
• In Vermont, physicians were too busy at the height of the epidemic to report cases, but the incomplete records reveal at least 23,000 sick and 1,800 dead, most during September and October.
• Virginia had more than 200,000 cases and 15,000 dead. Desperate doctors began to resort to unusual remedies, not sure what they were dealing with. In Alexandria, the town’s two doctors dosed their patients with belladonna and whiskey, while in Richmond one doctor fell back on an old remedy—soaking the feet of those affected in scalding water and then swaddling them with blankets until they sweated.
• In Alaska, entire villages of Eskimos were wiped out as those who survived the flu were too sick to hunt moose and chop firewood and died from starvation and the cold. A local schoolteacher reported that in her area, “Three [villages were] wiped out completely, others average 85 percent deaths.” Of the 750 who died, she estimated 25% “froze to death before help arrived.”
• Montana had one of the highest mortality rates, probably because its population was largely in the 20 – 40-year-old age range where death rates were highest. State epidemiologist Dr. John J. Syppy estimated that 1/3 of the state’s population got sick and the death rate was 8.6%, double that of Michigan, Minnesota, and Indiana.
• 8,549 Wisconsin residents died at the peak of the epidemic. “To gauge the magnitude of the crisis,” one historian wrote, “consider that more Wisconsin residents died during the six months of the influenza epidemic than were killed in World War I, the Korean War, and the Vietnam conflict combined.”
• California suffered financially from the pandemic, as movie houses were shut down across the nation to contain the spread of the disease. Schools were closed in Los Angeles for four months. San Francisco is considered a model for frank communication of the government and health department officials. Citizens were invoked to wear masks in public at all times with the popular rhyme: “Obey the laws, and wear the gauze. Protect your jaws from septic paws.” 3,500 in the city died, however.

Modern researchers believe masks are most helpful on the sick, not the well, pointing out that they are easily contaminated and do not prevent the virus from accumulating elsewhere on the body. However, Dr. Howard Markel led a study of “non-pharmaceutical intervention” in 43 cities during the Spanish Flu pandemic to study the effectiveness of “social distancing” measures—closing schools, banning crowds, and quarantining the sick. His group found that cities that implemented such measures substantially reduced the levels of infection. St. Louis closed its schools when the death rates were relatively low, thus reducing mortality rates in that city by 70%. Cincinnati delayed until mortality rates were twice as high (46 per 100,000) and in consequence, the measure only reduced the deaths by 45%.

For more on the 1918 flu pandemic, click here.