Through the back window of her Soddy-Daisy home, Dora Sowell watches the Tennessee River. On warm summer days, it teems with water sports enthusiasts. But on this cool, gray morning in early February, she watches the water and thinks about something far more grim.
She's waiting for influenza season to subside, knowing her fate may be different than it was nearly 100 years ago, when she survived the Spanish flu.
"I've always worried about any time the flu comes around, because I don't want to have it again," the 99-year-old said. "At my age, it probably would be a killer."
In 1918, the dangers of the influenza virus - at the time often called "grippe" - were nothing new. It was a known killer. And flu shots, antiviral drugs to fight the pathogen or antibiotics to treat potential secondary infections like pneumonia didn't exist.
But that year would prove to be unlike any epidemic ever recorded.
It's estimated the Spanish flu affected at least a quarter of the world's population, with the death toll reaching between 20 million and 50 million people. More than 675,000 Americans were sickened, 8,000 of those in Tennessee, but some estimate the mortality was much higher because many deaths likely went unreported.
Sowell was one of the lucky ones.
World War I was in its fourth and final year when the virus began to take hold.
While it came to be known as Spanish flu, some researchers now believe it originated in Kansas in an Army training camp, possibly when a form of avian influenza jumped from migratory birds to swine and then to humans. Others argue the outbreak began elsewhere.
Regardless of its origin, the virus surfaced in early 1918 and circulated during spring with little attention, except when it infected the Spanish king. As a neutral country during the war, Spain reported heavily on the event, which led other countries to coin the illness "Spanish flu."
By August, the disease began sweeping the globe.
Dr. Mark Anderson, an infectious disease specialist at CHI Memorial, said the movement of soldiers and depleted supply of medical staff because the world was at war created the "perfect storm" for a pandemic.
Mortality was high in people younger than 5 and older than 65, who generally have weaker immune systems that leave them more susceptible than healthy adults. But a unique consequence of the 1918 virus was its impact on healthy people between the ages of 20 and 40.
And by the end of its approximately 15-month run, the Spanish flu had caused more casualties than World War I.
Sowell was 3 months old and living with her family in Córdoba, Argentina, when she became sick in November 1918.
Her mother later described to her the horror of the event.
"She told me that on three or four occasions she thought I was dead already," Sowell said.
"She tried to give me fluids, and she tried to keep me asleep and well covered, and I think she gave me aspirin," she added. "That was the only thing she could give me, just little baby aspirin - there was nothing else to do at that time."
The illness lasted weeks of Sowell's young life as she slowly recovered. It also claimed the life of her cousin.
The detail remains etched in her memory.
"They didn't have enough time or wood to make the coffins, they were just making them out of plywood and burying people in plywood," she said.
The Chattanooga region wasn't spared from the misery.
The epidemic first appeared at Camp Greenleaf - a medical officer training site during the war - in Fort Oglethorpe on Sept. 25, when 26 soldiers fell ill.
For six weeks, influenza ravaged the area.
A local newspaper's headline on Oct. 9 read, "Public Health Authorities Determine To Stamp Out the Influenza at Once," but the virus proceeded to devastate Chattanooga.
That same day, all public places, including schools, churches and theaters, were forced to close.
Desperate pleas for nurses, doctors - already in short supply - and automobiles filled the pages, along with tragic stories of entire families stricken. The sheriff worked 36 straight hours as jailers and deputies fell victim.
By mid-October, the number of estimated cases surpassed 5,800 while many went unreported, according to the Chattanooga and Hamilton County Medical Society's centennial history.
"Every hospital in the region performed at maximum capacity; civilian and military medical personnel and nurses worked until exhausted," the book states.
"Doctors and nurses gave unsparingly and courageously," according to nursing school records.
"The Baroness Collection," a book of Erlanger hospital's first 100 years, states, "Erlanger cared for a large number of patients with the illness, including many soldiers from Fort Oglethorpe."
At Camp Greenleaf, "thousands suffered and military funerals cast a heavy gloom over victory," according to another account from the medical society.
Officers operated a large isolation tent, and severe cases were transferred to the camp's General Hospital No. 14.
The outbreak within the camp was over by Oct. 26, but during the month since it first hit, there were 2,343 cases of influenza and 1,200 cases of pneumonia admitted to the hospital, ending in 325 deaths, according to records from the U.S. Army Office of Medical History. An estimated 25 percent of the pneumonia cases resulted in death.
"The epidemic greatly interfered with the activities of the camp," the records state. "Few men were received during the period and few organizations departed."
Industry in Chattanooga also ground to a halt, but little sympathy was paid to factory workers.
"It is decidedly unpatriotic for persons - especially industrial workers - to give up the performance of their duties for any lesser cause than actual illness," public health officers stated.
A news article from Oct. 13 detailed the impact on industry: "Practically every plant and industry is Chattanooga is seriously crippled as the result of the wave of influenza that is passing over the city."
Mills and factories at the foot of Missionary Ridge seemed hardest hit.
At the Thatcher Spinning Mills, Standard Processing Company and Chattanooga Bottle and Glass Company, 50 percent of workers were out sick.
"Distressing conditions exist" for families in East Chattanooga, East Lake and Alton Park, the article states. "Fathers and mothers and even children have been found unable to care for each other, and only through the thoughtfulness of their superiors have been saved from extreme suffering."
New cases began to subside by mid-October, but mortality continued to rise as those unable to ward off continued infection succumbed.
At the peak, 38 civilians and 53 soldiers died in one day. By Nov. 7, the death toll from the military camps and the city was 1,000.
"I do not remember that there were a great many cases of pneumonia, or many fatalities," Dr. E.B. Wise, city physician, said in a news article. "If I were to emphasize the distinctive differences between this epidemic and the former ones, I should say it is in the tendency of the present type of [the flu] to run into bronchial pneumonia."
The epidemic in Nashville was "one of the most severe in the country," according to the University of Michigan Center for the History of Medicine website.
The city saw 40,000 influenza cases and 392 deaths during the epidemic, with an additional 10,000 cases and 267 deaths occurring at the Old Hickory powder plant, a prominent DuPont factory outside the city that produced smokeless powder for the war. The result was an excess death rate of 610 per 100,000, slightly higher than that of Birmingham (592) and significantly higher than Atlanta (414) per 100,000 people.
"It's just terrifying, absolutely terrifying," Anderson at CHI Memorial said. "Can that happen again? I certainly would not say anything is impossible."
The world has faced three other flu pandemics, which occur when a new strain of the virus emerges, since 1918: the Asian flu in 1957, the influenza A (H3N2) virus in 1968, and a novel influenza A (H1N1) virus that appeared in 2009.
Today, society is more equipped to protect itself from pandemic flu - we have improved medicine and technology - but experts know that influenza still poses a significant public health threat.
The virus "compels us to be prepared," because it is the only known pathogen to circulate globally and affect so many lives every year, said Colleen Jonsson, the Van Vleet Chair of Excellence in Virology at the University of Tennessee Health Science Center.
"It's one that really calls attention by the scientific community because of the nature of this infection," Jonsson said.
The flu has two distinct surface markers called antigens, hemagglutinin and neuraminidase, representing the H and N in the virus's name, and these antigens are constantly changing.
Anderson said the world desperately needs a universal flu shot that works for all strains and isn't required to be given each year, but this "antigenic drift" is what makes creating a vaccine so difficult.
"It's not that your immunity wanes - it does - but the bigger problem is the antigenic drift may be just different enough so the vaccine doesn't work very well or in some cases doesn't work at all," he said, which is a problem with this year's vaccine.
Amber Smith, an assistant professor of pediatrics who studies infectious diseases at the University of Tennessee Health Science Center, said that it's normally once we're in the midst of a bad influenza season that people question influenza research.
Over the past months, hospitalizations and deaths, particularly in children, seniors and people with chronic conditions, from influenza are the highest in recent years, and experts predict the season will continue for weeks.
"One hope is that for somebody to see a season like this one as a reminder," Smith said. "Flu knows no name. Anybody can get infected with influenza. Anybody can have a severe infection or even maybe die from influenza."
Smith said this year's vaccine does have some efficacy and also protects against other strains of the virus that are circulating.
Sowell isn't taking chances. She's received an annual flu shot every year since the 1960s and encourages others to get one, as well.
Although in 2018 there are better tools to detect and respond to influenza, there are also new challenges, such as the ability for the virus to spread faster through air travel and the global economy.
"If a totally, utterly new virus emerged, particularly that's from an animal species so that no humans on earth have any sort of resistance to it, how much damage could that do before we could react to it?" Anderson asked, adding that if a virus hit in the aftermath of a disaster that significantly compromised public health capabilities, "it could be similar to 1918 again."
"I'm still scared," he said. "It doesn't keep me awake at night, but it might."
Contact staff writer Elizabeth Fite at email@example.com or 423-757-6673.