Concerns are rising among Iowans about the Ebola virus after an infected American doctor was brought from western Africa to Atlanta over the weekend and another infected health care worker should arrive in the U.S. on Tuesday.

Iowa native Libby Casavant is working as a hydrologist with non-governmental organizations in Liberia and says she’s beginning to wonder how safe it is to stay there. “I have several friends who are in the Peace Corps and just yesterday they got the news that they’ll be leaving and going back to the U.S. for at least one month,” Casavant says. “The fact that she’s being evacuated has really made me think about how serious this is getting.”

Dr. Stanley Perlman, a professor of microbiology and pediatrics at the University of Iowa, says there’s a possibility Americans could carry ebola home without realizing it. Dr. Perlman says, “If somebody is not quite sick and gets on an airplane and isn’t screened properly leaving the areas where there’s high risk or a high number of cases, then that person could arrive in the U.S. and he, he or she, could expose some people on the airplane as well as people when he arrives.”

More than 700 people have died of Ebola in three west African nations in recent months, making it the largest outbreak since the discovery of the virus. Perlman and Casavant made their remarks on the Iowa Public Radio program, River to River.