The travel industry is optimistic about vaccinations unlocking vacations. The UK government is doing its best to kill the buzz.

“At the moment,” says Ryanair chief executive Michael O’Leary, “bookings have essentially collapsed. Nobody is flying up to Easter.” But he forecasts a rapid improvement, with a back-of-the-envelope estimate for April flights at 10 per cent of pre-pandemic levels, 20 per cent in May, 30-40 per cent in June and 50 per cent for July to September.

Yet a television advertisement from Ryanair that encouraged viewers to “Jab and go!” was last week banned by the UK’s Advertising Standards Authority, partly on the rationale that viewers would jam up doctors’ phone lines demanding an injection before they headed to the airport.

Having done little to stop the virus entering the UK for most of the pandemic, the government is now forcing travellers arriving from 33 countries to spend 10 days locked up in a hotel or risk 10 years locked up in jail. Any other arrivals must quarantine at home and be tested.

A government that introduced a dining scheme that exhorted people to “eat out to help out” earlier in the crisis now warns them against booking refundable holidays six months in advance. “Please don’t go and book holidays for something that is illegal to do, whether it’s here or abroad,” the transport secretary said this week.

Yet however precarious the current situation, companies and many tourists are looking at a successful vaccine rollout and expecting the rules will be relaxed before the summer.

Tui, Europe’s largest travel group, this week reported that more than half of its 2.8m summer bookings had come from the UK. “It's our strongest market and also the market with the best vaccination programme,” chief executive Friedrich Joussen told analysts. “That’s all good.”

This phenomenon exists in other fed-up northern hemisphere countries. US budget carrier JetBlue forecast last week that its full-year capacity would recover to 70 per cent of 2019 levels. Spirit Airlines said on Thursday that its bookings were picking up and it expected to be back to 2019 levels by the summer.

Payments companies are hopeful too. Forecasting 19 per cent revenue growth in 2021, PayPal highlighted travel as a particular driver as soon as the second quarter. “As people begin receiving vaccines, there’s pent-up demand,” said chief financial officer John Rainey. “People want to take that summer vacation in 2020 that they missed.”

Will governments try to stop them? Subdued populations, frightened by the winter increase in cases and deaths, have tolerated lengthy lockdowns. That is unlikely to persist for long after the March anniversary of widespread restrictions.

As O’Leary, head of Europe’s largest airline, puts it: “If the UK has everyone over-65 vaccinated by the end of March, most of Europe by the end of May, there will be extraordinary resistance among populations to being locked down and told you can’t travel abroad.”

There is one wrinkle. Ryanair’s banned advert showed a bunch of young adults jumping into a pool. But few countries will have fully vaccinated this group by the summer.

If countries are willing to accept unvaccinated tourists, that should not matter. But if vaccines become mandatory, then only older people will be travelling in the short term. That would mean a grey summer after all.