Ebola’s spread to the United States is "inevitable" due to the nature of global airline travel, but any outbreak is not likely to be large, US health authorities said Thursday.

Ebola's spread to the United States is "inevitable" due to the nature of global airline travel, but any outbreak is not likely to be large, US health authorities said Thursday.

Already one man with dual US-Liberian citizenship has died from Ebola, after becoming sick on a plane from Monrovia to Lagos and exposing as many as seven other people in Nigeria.

More cases of Ebola moving across borders via air travel are expected, as West Africa faces the largest outbreak of the hemorrhagic virus in history, said Tom Frieden, the head of the US Centers for Disease Control and Prevention.

The virus spreads by close contact with bodily fluids and has killed 932 people and infected more than 1,700 since March in Sierra Leone, Guinea, Nigeria and Liberia.

"It is certainly possible that we could have ill people in the US who develop Ebola after having been exposed elsewhere," Frieden told a hearing of the House Subcommittee on Africa, Global Health, Global Human Rights and International Organizations.

"We are all connected and inevitably there will be travelers, American citizens and others who go from these three countries -- or from Lagos if it doesn't get it under control -- and are here with symptoms," he said.

"But we are confident that there will not be a large Ebola outbreak in the US."

There is no treatment or vaccine for Ebola, but it can be contained if patients are swiftly isolated and adequate protective measures are used, he said.

Healthcare workers treating Ebola patients should wear goggles, face masks, gloves and protective gowns, according to CDC guidelines.