US ambassador West Africa
U.S. Ambassador to the U.N. Samantha Power speaks to members of the Security Council during a meeting on the Ebola crisis at U.N. headquarters in New York, September 18, 2014. REUTERS/Shannon Stapleton

(Reuters) - As the U.S. Ambassador to the United Nations embarked on a trip to West Africa, new rules in three U.S. states mandating quarantine for health workers returning from the Ebola-stricken region drew criticism, even as some U.S. lawmakers called for a travel ban on the three worst-hit countries.

Samantha Power, a member of President Barack Obama's cabinet, left Washington on Saturday bound for Guinea, Liberia and Sierra Leone. Obama has resisted Republican calls for a travel ban on advice from health officials who say such a measure would be counter-productive.

Along with New York and New Jersey, Illinois has now imposed quarantines for anyone arriving with a risk of having contracted Ebola in West Africa. But the first person isolated under the new rules called her treatment a "frenzy of disorganization."

Kaci Hickox, a nurse returning from Sierra Leone, arrived at Newark airport on Friday and was questioned by protective-gear clad officials amid what she said was a mis-diagnosis of fever, followed by a transfer to a hospital isolation tent.

Hickox said she feared for what lies ahead for other U.S. health workers trying to help combat the epidemic that has killed thousands in West Africa.

'FRENZY OF DISORGANIZATION'

"Will they be made to feel like criminals and prisoners?" she wrote in an article published on Saturday by The Dallas Morning News on its website. (bit.ly/1w4Vi4J)

"I am scared that, like me, they will arrive and see a frenzy of disorganization, fear and, most frightening, quarantine," wrote Hickox, of charity Doctors Without Borders.

New York and New Jersey imposed 21-day quarantines after a New York City doctor was diagnosed with the disease on Thursday, days after returning home from working with patients in Guinea.

The doctor's case and the fact he was out and about in the city in the period before his symptoms emerged set off renewed worries in the United States about the spread of the disease.

Illinois will now also require a mandatory quarantine of anyone who has had direct contact with Ebola patients in those countries. The quarantines imposed by the three states exceed current U.S. government guidelines, although the Obama administration is discussing similar measures.

Ebola, spread through direct contact with bodily fluids from an infected person, is not transmitted by people who are not showing symptoms.

ARRIVAL TREATMENT CRITICIZED

Hickox's account of her treatment echoed concerns of critics of the mandatory quarantines who say they could discourage Americans from going to help control the epidemic.

Ebola has killed almost half of more than 10,000 people diagnosed with the disease - predominantly in Liberia, Sierra Leone and Guinea - although the true toll is far higher, according to the World Health Organization.

Doctors Without Borders has criticized Hickox's treatment.

New Jersey Gov. Chris Christie, asked by reporters about the nurse's complaints, said his first obligation was the safety of the people of New Jersey.

"Inconvenience that could occur from having folks that are symptomatic and ill out amongst the public is a much, much greater concern of mine," he said.

(Additional reporting by Barbara Goldberg, Natasja Sheriff and Yasmeen Abutaleb in New York; Writing by Edwin Chan; Editing by Chris Michaud and Richard Borsuk)