Oct 21 (Reuters) - A new poll on Tuesday showed Ebola ranks well behind the economy, jobs and other issues among America's top problems, while a law enforcement official warned about Ebola-related scams promising protection against the virus that has killed thousands in West Africa.

Ebola debuted in the top 10 concerns of Americans but remained far behind five other issues: the economy, dissatisfaction with government, jobs, healthcare and immigration, the Gallup polling organization said.

The poll was conducted from Oct. 12-15, before Monday's announcement that 51 people had been removed from Ebola watch lists in Texas after showing no signs of symptoms for 21 days.

The removal of dozens of people from monitoring may have eased concerns about the spread of the disease in the United States, where three people have been diagnosed with the virus that has killed more than 4,500 people, mostly in Liberia, Guinea and Sierra Leone.

New York Attorney General Eric Schneiderman issued a consumer alert on Tuesday about bogus Ebola preparedness kits and preventative medications.

"Scammers are shamefully exploiting this moment of heightened concern about public health to defraud good people," Scheiderman said in a statement.

There are no U.S. government-approved vaccines, medications or dietary supplements to prevent or treat Ebola.

Such schemes aim to prey on American's worries over the virus after the first patient diagnosed in the United States died in Dallas this month. Concerns spread after another infected patient flew from Texas to Ohio, and numerous U.S. hospitals have been on alert for possible cases.

Some U.S. airports have also begun screening passengers arriving from West Africa.

A study published in The Lancet medical journal on Tuesday said three Ebola-infected travelers a month would be expected to board international flights from West African countries suffering epidemics of the virus if no effective exit screening existed.

Researchers used modeling based on this year's global flight schedules and last year's passenger itineraries, along with current epidemic conditions, to conclude that 2.8 people with Ebola, on average, would board international flights every month. They said exit screening was far more effective than screening at the point of arrival.

Some U.S. lawmakers have called for a travel ban from West Africa to help stop the spread of the virus.

U.S. Senator Marco Rubio, a Florida Republican, said on Monday he planned to introduce legislation when the Senate returns next month that would impose travel restrictions by creating a temporary ban on new visas for people from Liberia, Guinea and Sierra Leone, the hardest-hit countries.

(Writing by Jim Loney; Editing by Meredith Mazzilli)

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