Q: How do non-smoking actors portray characters who smoke in movies and shows? Are they smoking actual cigarettes or a specially created product that appears to be a cigarette?

—Tim Schnabel, Monroe

A: Actors who prefer not to smoke cigarettes in scenes for movies and TV shows often will use herbal cigarettes that "Mad Men" star Jon Hamm told the Independent, a British newspaper, "taste like a mix of pot and soap." The show is filmed in California, which doesn't permit smoking in buildings, so Hamm has to smoke many herbal cigarettes in each episode.

They are made from “clover, marshmallow (the plant) leaves and rose petals, suffused with ginseng, vanilla or menthol.” They don’t include nicotine but can be addictive and produce carcinogens. Prop masters use several recipes to make fake cocaine and other drugs for movies. They include cornstarch mixed with baby powder for cocaine and powdered lactose or a vitamin B powder if the actor must snort the fake drug.

Q: If you catch Ebola and are cured, can you catch it again?

—Art Mathewson, Marietta

A: There is no scientific evidence that has proven that an Ebola survivor is immune from the virus. But health officials say they don't know of a case where "a person who has been infected who has recovered and has been infected again," Marie-Paule Kieny, the World Health Organization's assistant director-general for health systems and innovation, told Bloomberg News. Doctors Without Borders said it hasn't seen a case where a survivor became "reinfected with the same strain of virus," the article stated. There were 11 survivors working with doctors at a hospital in Monrovia, Liberia, last month.

Andy Johnston wrote this column. Do you have a question about the news? We’ll try to get the answer. Call 404-222-2002 or email q&a@ajc.com (include name, phone and city).