Any visitor from overseas who doesn't quarantine themselves for two weeks as required should be jailed, according to Professor Sam McConkey.
The infectious diseases specialist at the Royal College of Surgeons says passengers and airlines need to step up and take responsibility, and that the regulations need to have 'teeth'.
Direct passenger flights from several US cities to Ireland have resumed recently, including from areas such as Texas which are seeing a surge in COVID-19 cases.
Currently, anyone arriving here is required to fill out a form saying where they will be self-isolating for two weeks - although the quarantine itself isn't legally enforceable.
Professor McConkey said simply asking tourists to self-isolate isn't enough to protect us.
He observed: "We've been almost unique in the world of having open borders to everywhere - I understand why that's the case, because we're a very small open economy and we really need some people to be able to travel.
"[But] there needs to be regulations with teeth, so that if people don't follow them then you are more or less looking at three months in Mountjoy.
"All it takes is 10 or 20 American tourists in Mountjoy for a month or two, and suddenly the message is going to get through.
"I think we need a sense of justice and a sense of fair play... that if people are flouting the regulations, that there are fairly tough, predictable consequences."
The Government is set to discuss travel restrictions later this week, including a potential 'green list' of countries deemed safe to travel to.