A majority of Americans support banning all flights to the United States from countries experiencing an Ebola outbreak, an exclusive NBC News online survey reveals.

The survey, which was conducted by SurveyMonkey and then weighted for age, race, sex, education and region to match U.S. Census data, found that 58 percent of Americans want a ban on incoming flights from West African countries hardest hit by the virus, such as Liberia, Guinea, and Sierra Leone. Twenty percent of respondents opposed a travel ban, and the rest said they didn’t know. The survey was conducted a day before the first person diagnosed with Ebola inside the U.S. died Wednesday.

The federal Centers for Disease Control and Prevention and U.S. Customs and Border Protection on Wednesday announced new screening procedures at five American airports that see the most travelers from Guinea, Liberia and Sierra Leone: New York’s JFK International Airport, Washington-Dulles, Newark, Chicago-O’Hare and Atlanta. Staff will question and take the temperature of everyone coming from those countries and screen for signs of the illness. Approximately 150 passengers come to the U.S. from those countries each day, officials said.

The survey found that 51 percent of respondents said they were worried there would be an Ebola outbreak in the United States, and 30 percent worried they or someone in their family would be exposed to the virus.

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By an almost 2-1 margin, those surveyed disapproved of sending U.S. troops overseas to help contain the outbreak.

Most Americans surveyed said they did have an accurate understanding of how the deadly disease is spread, with 72 percent correctly answering that it is communicated through bodily fluids.

“People actually have to have a decent understanding in how you contract Ebola. Only 10 percent said through the air, and 15 percent said through the skin,” said John Lapinksi, an associate professor of political science at the University of Pennsylvania, who is also director of elections at NBC News and was part of a team of academics who weighted the survey results. “The knowledge [result] is not trivial.”

The Ebola outbreak, the largest in history, has sickened 8,033 people and killed 3,879 as of Wednesday — and the World Health Organization said those numbers are almost certainly an underestimate. Also in the U.S., NBC News freelance camera operator Ashoka Mukpo is being treated for the disease at the Nebraska Medical Center and an unnamed American doctor is being treated at Emory University Hospital in Atlanta.

The survey found that people trust the CDC more than their local health departments to prevent an outbreak of Ebola in the U.S. The Dallas hospital where the Ebola patient who died, Thomas Eric Duncan, 42, was treated has come under fire after it initially sent Duncan home after the Liberian national complained of symptoms that turned out to be the deadly disease, creating a delay in treatment.

Seventy-six percent of those surveyed said they trusted the CDC to prevent an Ebola outbreak in the U.S. That compared to 62 percent who said they trusted their state health department to take the proper steps to prevent an outbreak.

The survey was conducted Tuesday, Oct. 7, and has a margin of error of 4.6 percent. The company conducted the survey by sending e-mails to 2,517 people; of those, 1,045 started the survey and 1,010 completed it. Those e-mailed were chosen from those who completed other surveys on the SurveyMonkey platform, in age in sex proportions that attempted to mirror U.S. Census numbers. All were over the age of 18.