The deadly outbreak of Ebola in West Africa that has killed more than 1,500 people in four countries since May is a powerful reminder of just how deadly — and unpredictable — a virus can be. Ninety-six years ago this week, the city of Boston was dealing with its own viral outbreak — the start of one of the deadliest natural disasters to ever occur.

A staggering number of people died in 1918. Fifty to 100 million worldwide, by some estimates. The terrifying disease in question? Not Ebola. The flu.

"This was a terrifying disease," said John Barry, author of The Great Influenza. There was real fear. People could bleed not only from their nose and mouth, but even from their eyes and ears. People could die 24 hours after the first symptoms."

In the spring of 1918, communities across the globe saw a small spike in influenza cases. Barry said scientists and doctors knew there was something going on, but it was not particularly lethal. In fact, it was so mild that authorities weren’t sure it was influenza. So, nobody batted an eye when two Navy seamen — stationed on Commonwealth Pier in Boston — entered the sickbay on August 27, 1918 with flu symptoms. The next day, there were eight more. The following day, 58.

"It’s not clear why, but both at Camp Devens and on the wharf where there was a Naval facility,” Barry said. "It was the first eruption of what was very plainly a very lethal pandemic."

Within a week, soldiers and sailors were dying. Thousands more were sick. With World War I on, and civilians a big part of the effort here on the home front it was only a matter of time before the disease spread beyond the barracks. By early September, sick civilians were overwhelming city hospitals. Officials here appealed to the Red Cross and the federal government for help. Nurses, medical supplies and the like poured in from other parts of the eastern U.S., Barry said.

But it wasn’t enough. By October, all hell was breaking loose in the city of Boston and communities across the Bay State.

"You close the schools, you close theaters, you close the bar, you basically cut down on all public interaction,” Barry said.

Morgues and cemeteries couldn’t keep up. Despite mounting deaths, wakes and funerals were discouraged. Even Sunday church services were eventually banned. All that was left to do was manage the chaos and let the disease run its course. By the end of 1918, nearly 5,000 Boston residents alone had died. Only Philadelphia and Pittsburgh were hit harder.

"At least 20 percent, possibly 30 to 40 percent of the entire population got sick," he said. "And probably 2 to 3 percent of the total population died."

Today we bandy the term “flu” about to describe everything from the sniffles to a sour stomach. We have seasonal vaccines and antiviral medications, we have NyQuil. But Barry points out that in 1918, options for treatment were limited, as was our understanding of the disease.

"In fact they did not even realize in 1918 what a virus was," he said. "Whether a virus was a very small bacteria or a different entity.”

But Dr. David Hooper, chief of the Infection Control Unit as Mass General Hospital, said that doesn’t mean valuable lessons weren’t learned. And many of those lessons guide the way we manage viral outbreaks today — from influenza to Ebola.

"Certainly in infectious diseases, in training aimed at that you learn about it. And in public health, epidemiology you would learn about it."

On the heels of the pandemic, waves of research led to breakthroughs in our understanding of what influenza is and how it works. And then there are the secrets buried deep inside the virus itself, still being revealed. In 2005, scientists reconstructed the 1918 strain using samples of genetic material from victims’ long dead lungs.

"We learned from the 1918 pandemic that travel of people is one of the ways that influenza can move around and spread in the population,” Hooper said. "And there’s ongoing work on that, understanding what the likelihood that a particular virus will cause severe disease based on its genetic makeup."

What they learn could prove invaluable when the next pandemic comes. And make no mistake, it's coming. Both Barry and Hooper said we'd be wise to remember 1918. Influenza is one tough little bug.

"We had one in 1918, 1957, 1968, 2009, we’ll have another one," Barry said.

"I think we always have to give great respect to the power of these types of viruses and other pathogens," Hooper said. "My guess is we’ll never be able to eliminate an influenza virus from the planet."

The deadly influenza pandemic of 1918, which killed at least three times more people than WWI, and wreaked havoc in all corners of the globe. Its first outbreak happened right here in Boston, 96 years ago this week.

Edgar B. Herwick III can be reached at