iStock/Thinkstock(WASHINGTON) -- While Ebola may have infected only one person in the United States, economists say fear of the disease can spread like contagion."People become afraid by talking to someone else who is fearful or seeing someone else get the disease," said Ross Hammond, economist and director of the Center on Social Dynamics and Policy at The Brookings Institution.Hammond, who studied the economic effects of closing American schools in 2009 in response to the H1N1 virus, said there are documented instances of fear spreading very rapidly. Those fears could have consequences that affect consumer behavior and businesses."When people become afraid of catching a disease, and they change their behavior or keep their kids home from school, or stay home from work or cancel a trip, that of course has economic effects," he said.Here are some potential consequences:ProductivityIn Texas, where the first person in the U.S. was diagnosed with Ebola earlier this week, some parents have already chosen to withhold their children from school in fear of contagion. That means people will have to say home with their children, possibly affecting the level of workplace productivity.In his 2009 study, Hammond had estimated that closing all U.S. schools in response to the H1N1 for four weeks would cost $10 billion to $47 billion.Wall StreetAirline stocks have dropped this week, in part, due to fears that the virus may hinder Americans' willingness to travel.Also, the World Bank estimated last month that the economic effect of Ebola in the hardest-hit countries of Liberia, Guinea and Sierra Leone, would be "catastrophic." In a global economy, that could impact American companies.Travel and TourismPeople may choose to not travel -- either internationally or domestically -- and that can affect the airline and tourism industry.Mead Over, senior fellow at the Center for Global Development, told ABC News that since Nigeria has succeeded in containing the outbreak, he expects the United States’ stronger public health system to quickly contain the disease in Dallas or if any other infected traveler arrives elsewhere.Any economic impact on the stock market or in travel is not the impact of the disease per se but the impact of largely irrational "aversion behavior,” Mead said. “The impact of aversion behavior on the markets is like a speculative bubble, but in reverse," he said, adding that he expects this “reverse bubble” to collapse in a matter of weeks, as Americans realize that a strong public health system can protect them.Meanwhile, Hammond's other research shows fear can help spread an epidemic as well as help contain it."So when the effects of something are severe, people tend to assume that it’s also somewhat more likely," he said.The disappearance of the Malaysia Airlines plane earlier this year, for example, may make people more concerned about air travel even though the probability of an incident may not have increased, he said.But Columbia Business School professor Amit Khandelwal said it's too early to know if companies are changing their business decisions."I’m not worried in the slightest about this, and I can’t imagine this holding back businesses from sending managers to Texas," he said. Follow @ABCNewsRadio !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="http://platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs");Copyright 2014 ABC News Radio

Will Montgomery(DALLAS) -- The Ebola patient in a Texas isolation unit has become so weak that he can no longer talk to his family on the phone, his nephew told ABC News.Thomas Eric Duncan, who is from Liberia, has been confined to an isolation unit at Texas Health Presbyterian Hospital in Dallas since he arrived in an ambulance on Sunday.The family had said earlier in the week they spoke with Duncan by phone and prayed with him on the phone, but that is no longer possible, Duncan's nephew Joe Weeks told ABC News."At first we were able to talk to him on the phone, but now he is just too sick to speak," Weeks said.Weeks lives in Kannapolis, North Carolina, along with Duncan's sister and 87-year-old mother. The mother and sister may travel to Dallas soon, Weeks said.A cleaning crew is expected to arrive Friday at the Ivy Apartments in Dallas where Duncan had been staying when he got sick from the Ebola virus. The crew was turned away on Thursday, but are expected to be admitted Friday.The cleaning crew is tasked with disinfecting all of the surfaces that Duncan could have touched, Dallas Judge Clay Jenkins said Thursday. The man’s clothes and sheets have been “bagged,” Jenkins said. Additionally, food has been delivered to the apartment for Duncan’s relatives.Weeks is concerned that the apartment has not yet been sanitized despite having four people confined to the apartment by a judge's order until they are determined to not be infected with Ebola, which can take as long as 21 days to incubate. Among the people in the apartment are a teenage boy and woman named Louise Troh, who traveled from Liberia with Duncan.“The house that he lived in has not been cleaned or disinfected. You still have four more people in there, that lived in that house and were allowed to leave and go shopping, go do other things that normal people would do,” Weeks said.Thomas R. Frieden, the Director of the U.S. Centers for Disease Control and Prevention, told ABC News Friday that the Ebola diagnosis offers new challenges for authorities.“It’s the first time we’re having Ebola in this country and the challenges are real in terms of what do you do with the waste, how do you move it, how do you dispose of it and we want to make sure that everything is done correctly,” Frieden said. “I’m confident that will get sorted out today.”The initial handling of Duncan's case has been the subject of controversy. Duncan first visited the hospital last Thursday, Sept. 25, but was allowed to leave the hospital despite telling a nurse he had come from West Africa. Duncan returned to the hospital by ambulance on Sunday.The hospital said in a statement Thursday that the physician and the nurses followed protocol, but his travel history didn't automatically appear in the physician's standard workflow.Weeks also had concerns that the hospital wasn't aware that Duncan may have been infected with Ebola. Weeks said that he called the hospital to report his concerns about Duncan’s condition -- and when he didn’t get the reaction he wanted, he called officials at the CDC and the Department of Health, at which point Duncan was put in isolation.“They had him in the ER, like any other patient, and I didn’t think that was the right procedure,” Weeks said.“I don’t know how long it was going to take, but I wasn’t trying to wait to see how long it was going to take, so I pre-empted and called CDC and reported that there might be a possible Ebola case in Texas. But the hospital was not doing what it needed to do at that time,” he said.Dallas and federal health officials are tracking all the people who may have come into contact with Duncan and so far that figure is about 100 people.Duncan, who worked as a driver in Liberia, flew to Brussels on Sept. 19. He continued to Washington’s Dulles Airport, before flying to the Dallas-Fort Worth Airport on a United Airlines flight, arriving on Sept. 20.Although American Ebola patients have been treated in the United States prior to this diagnosis, they all contracted Ebola in West Africa. Ebola has killed more than 3,300 people, with nearly 7,200 cases reported since the outbreak began in March. More ABC news videos | ABC Entertainment News Follow @ABCNewsRadio !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="http://platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs");Copyright 2014 ABC News Radio

A person in Hawaii was placed in isolation after exhibiting possible symptoms consistent with Ebola, state health officials said.