As Liberia struggles to contain the deadliest Ebola outbreak on record, health workers say that fear of the disease, and the stigma of being identified as a possible carrier, is creating a hostile environment for those seeking treatment.

That terror was on display on Monday in the Liberian capital, Monrovia, where at least 270 people have already died of the illness, when a man suspected of having the disease wandered out of a treatment center and sowed panic in a nearby market.

The incident, which was captured on video by witnesses, showed the man, wearing a medical bracelet, being confronted by angry and worried bystanders. He was then surrounded by health workers in yellow protective suits from the international medical group Doctors Without Borders, who eventually bundled him into the back of a pickup truck and returned him to the clinic.

Sophie-Jane Madden, a press officer for the medical aid group — which was founded in Paris in 1971 as Médecins Sans Frontières and is often referred to by the French initials M.S.F. — said in a telephone interview from Monrovia that the man had become disoriented while waiting for an evaluation at the group’s new clinic for patients suspected of having Ebola. After he was brought back from the market and given further medical treatment, he was eventually discharged.