Customers at a restaurant in Tralee, Co Kerry, are being temperature checked and asked if they have been abroad.
If they have not quarantined, they are being politely refused entry.
Two groups of US diners were turned away from the Croí Restaurant in the historic Princes Street quarter of Tralee after admitting they had not quarantined, according to its chef Noel Keane.
Mr Keane said that the tourists were drop-in diners who were turned away over two days last week. One group was of three people, the other a party of four.
While one group did not object to being turned away, a person in the other group responded by saying the Covid-19 pandemic was "over-hyped", Mr Keane explained.
"Basically they did not believe the pandemic was serious," he added. "I feel I have a duty of care to staff and customers to provide the safest possible environment."
He stressed that all diners at the restaurant have their temperatures taken digitally at the door. Mr Keane said that nobody has failed the temperature test so far.
American tourists frequently visit Co Kerry towns during the summer months. However, due to the Covid-19 pandemic, the number of visitors this year have dropped.
This year's 4 July parade and festival were cancelled, although Killarney Cllr Brendan Cronin raised the American flag shortly after day break over the Killarney Town Hall as usual.
While Killarney was busy with Irish people holidaying in the Co Kerry town, there were very few hired cars with Americans.
The Park Hotel in Kenmare, which is normally popular with US tourists, had only Irish residents staying there, according to concierge at the hotel.
Meanwhile, the annual Birds Euroshow Funfair, which has taken place in Killarney for more than 60 years, will not go ahead this summer.
In a statement, Kerry County Council said that in the interests of public health, it was agreed that the funfair would not take place this year.