About 200 aircraft cabin cleaners at La Guardia Airport in New York say concerns over the recent Ebola outbreak are one reason they've walked off their jobs.

Organizers of the strike by workers at Air Serv, who clean cabins and restrooms on Delta aircraft under a contract with the airline, say they expect the protest to last at least a day.

The workers, who remove garbage and human waste from aircraft, complain they are not provided with sufficient protection, and the recent Ebola scare has prompted them to take action, protest organizers said.

"The issues happened way before Ebola, but it's now come to a head," says Rob Hill, vice president of 32BJ Service Employees International Union, which the Air Serv workers voted to affiliate with earlier this year.

"The workers are really worried because they tend to be exposed to bodily fluids," while cleaning out bathrooms, union spokeswoman Amity Paye said.

Between 35 and 40 people walked off their jobs Wednesday and Thursday, union spokeswoman Elaine Kim said.

Although as many as 200 workers may become involved in the walkout as more shifts are included, flights have not been delayed as Air Serv workers who left their jobs are bring replaced by other contractors and by Delta employees, the airline said.

The U.S. government has announced that this weekend workers will start checking temperatures and health histories of passengers arriving at New York's John F. Kennedy airport from Guinea, Liberia and Sierra Leone, the three African countries hardest hit by the Ebola outbreak.

The program will be expanded next week to include Washington Dulles, Chicago O'Hare, Atlanta Hartsfield and Newark Liberty.

Ninety-four percent of flights from the three African nations to the United States land at one of those five airports.

The effort represents the first organized attempt to improve health security at entry points for foreign travelers into the U.S. since the virus was first found in a patient here last month.

Suggestions by some, including Sen. Ted Cruz of Texas, that air travel to the U.S. from West Africa be restricted, have been rejected by the Obama administration.

The temperature and health history checks were announced just shortly after the death of the first patient whose diagnosis of Ebola was made in the United States.

Liberian Thomas Eric Duncan, who had come to the U.S. to be reunited with his family, died in a Dallas hospital Wednesday.

Modern air travel has made global health concerns more pressing, experts say.

"We are a global village," says Howard Markel, a University of Michigan professor of the history of medicine "Germs have always traveled. The problem now is they can travel with the speed of a jet plane."