And it’s been named not by the WHO, but a furious Michael O’Leary.

Ryanair lost €2bn of its value last Friday amidst a new blitz of travel curbs and lockdown fears. And its CEO was in blistering form this week, condemning “the latest Nphet/Government gobbledygook travel advice”.

Amid the bluster were genuine questions about how exactly Ireland’s new travel testing regime will function from 00.01AM tomorrow.

For example, how are airlines or officials to determine what a “professionally done” antigen test is or looks like, especially if it’s in a foreign language?

All over Ireland, travel agents have been fielding similar queries.

Do I have to test even if I’m fully vaccinated? (Yes).

What about the kids? (They’re exempt, if under 11).

What if I test positive overseas, or don’t present a negative test on arrival? (You can't travel, or may face a fine, or worse).

"It’s caused an awful lot of upheaval,” says Maura Fahy of Fahy Travel Worldchoice in Galway.

This week, her team has been fielding queries from families booked to fly to Lapland, people seeking to push winter trips to spring, and some who have simply “let their flights go”.

"A lot of people are quoting the Munster rugby team,” she says. “What happens if you get stuck abroad?”

But she remains hopeful. Ms Fahy agrees with the testing requirement, and feels people accept that restrictions are necessary to facilitate safer travel in a pandemic. Her team works hard to get the latest updates out to customers ASAP.

But almost two years into the pandemic, the latest confusion and uncertainty is also taking a toll.

“It's just upsetting people, to be honest. It has kind of rocked their confidence, and we just don’t need it at the moment,” she says.

All told, the EU's Covid Cert system has held up fairly well since its formal launch what feels like 70 years ago, last July 1. One of its driving philosophies was to create a co-ordinated system that travellers and the industry could rely on. That has largely worked. Passenger numbers have slowly been picking up.

Now, it feels like we're back to chaos and herding cats.

In the hours and days after Omicron reared its ugly head, snap reactions have been head-spinning. Different countries doing different things. Nobody wants to make the mistake of moving too slowly. But it feels panicky.

In the latest twist, the US is weighing whether to shorten its test requirement to within 24 hours of travel, and introduce a self-quarantine period of seven days.

“I’d love to see the speculation reduced, says Martin Skelly of Navan Travel. “Our phones have got busy with impending travellers looking for clarity."

He also points out that passengers leaving Ireland on short trips can theoretically take their tests at home and, provided they are back within 72 (PCR) or 48 hours (antigen), not have to go through the hassle of testing overseas.

However you look at it, this is a stressful time for people hoping to holiday, reunite or come home over Christmas. So what are your options if you have booked, or want to book, a trip?

In the first instance, talk to your travel agent or tour operator. It’s their job to be on top of the rules, what they mean for you, and what your cancellation or postponement options are.

Anyone travelling should have adequate insurance, and can check reopen.europa.eu and dfa.ie/travel for the latest travel requirements for your destination.

And don't forget to fill in Ireland's Personal Locator form and take your PCR or antigen test before return.

If you are not travelling imminently, wait and see. There’s a storm of updates and speculation right now, and there is simply no point trying to second-guess what will happen.

Everybody is praying Omicron will blow over, and not cancel Christmas, but for now we just don't know.

We’re all hoping for more clarity, and less gobbledygook.