Although recent unprecedented efforts to contain the novel coronavirus stemming from China may fail to prevent its global spread, infectious diseases expert Stephen Morse has emphasized that the public should be vigilant but not in a panic as the epidemic runs its course.

Morse, 68, a professor of epidemiology at Columbia University Medical Center who has been involved in World Health Organization coronavirus meetings, described the likely outcome as similar to influenza pandemics witnessed in past decades.

"I think that the containment efforts have been heroic and unprecedented, they're Herculean efforts ... (which have) bought some time and slowed down the progress" of the coronavirus, achieving "limited containment," Morse said in a recent interview with Kyodo News.

"But we also probably have a number of places where it's circulating the way influenza is and we're just not yet aware of it until somebody gets sick enough that we notice," he added.

With a vaccine against the novel virus an absolute minimum of six to eight months away, Morse said, "I think probably we will be in a period where we won't be able to contain it and we won't have a vaccine, so we'll have to live with it."

First reported in the central Chinese city of Wuhan in December, the coronavirus has since spread to dozens of countries. There have been over 100,000 confirmed cases around the world so far, leading to more than 3,800 deaths, according to WHO data.

Though definitions of the word "pandemic" can differ, Morse said it applies to the current situation in the technical sense of an epidemic with wide geographical spread, though not in the colloquial sense of being "like a death sentence."

He said the majority of people who contract the virus are likely to experience mild symptoms, but those in higher risk categories such as the elderly and people with pre-existing conditions are more vulnerable as the pneumonia-causing illness spreads.

Amid an increase in preventive measures against the epidemic such as travel restrictions, school closures and the cancellations of large-scale public events, it has become uncertain whether Japan will hold the Tokyo Olympics beginning in late July as scheduled.

Morse cautioned that the coronavirus situation has been changing rapidly and could be completely different by May, when Olympic organizers would presumably need to make the decision. If the virus has spread extensively around the world by then, it could actually be safer to travel as many people would be recovering, and perhaps the Games could be held as planned.

"On the other hand, it's quite possible that this process will be prolonged. And if it is, then obviously people would want to be very cautious," Morse said, indicating the Olympics could end up being canceled or postponed in that case.

He also suggested that travel bans may not be sustainable or effective as the list of places with substantial clusters of infections grows.

"Usually by the time you have travel restrictions, it's too late to do much good," he said. "We can keep it up as long as it's still working to some degree, but I think that at some point, it will be impossible to use geography as a guide."

In past decades, pandemics involving novel strains of influenza have caused widespread infections resulting in death in around 0.5 percent or less of known cases, as compared to a typical mortality rate of around 0.1 percent for the seasonal flu.

The deadliness of the new coronavirus is hard to estimate at this point, since the first cases noticed tend to be severe and disproportionately result in death, but Morse believes the mortality rate is likely to be on par with other pandemics since the mid-20th century.

As the virus is passing through the human population for the first time, with no immunity yet built up against it, "almost everyone in the world is essentially susceptible," Morse said. He suggested that if the virus were to spread without hindrance, it could eventually infect up to 60 to 70 percent of the world's population.

Following the pandemic phase, the virus is likely to survive and could return in the future with less disruptive effects thanks to vaccines and immunity, similar to influenza strains that periodically circulate among humans.

"I don't think it's going to be possible to completely eliminate" the coronavirus, Morse added.

Noting that other viruses known to exist have the potential to trigger further epidemics, he emphasized that preparedness is key for any future containment efforts.

"We can stop them early if we get to them early," Morse said. "It's much harder once they gain a foothold."