Cruise lines in America have been thrown a lifeline after the US Centers for Disease Control and Prevention issued a letter saying lines will be able to resume sailing by the mid-Northern Hemisphere summer.

But one line immediately signalled that cruisers should expect the price of sailings to increase once voyages resume.

The CDC said 95 per cent of cruisers and 98 per cent of crew should be vaccinated against COVID-19 to avoid test cruises, which lines have avoided as too expensive.

Under the conditional-sail order of October, 2020, cruise operators were required to conduct test voyages and apply for a certificate at least 60 days before offering passenger cruises.

“This puts cruise ships closer to open-water sailing sooner,” the CDC said.

“We acknowledge that cruising will never be a zero-risk activity and that the goal of the conditional-sailing order’s phased approach is to resume passenger operations in a way that mitigates the risk of Covid-19 transmission onboard cruise ships and across port communities,” Aimee Treffiletti, head of the maritime unit within the CDC’s COVID-19 global migration task force, said in the letter to cruise leaders.

The CDC said passenger voyages could restart by mid-July if operators submit documents related to port agreements as soon as possible. Cruise operators can enter into an agreement with multiple ports as opposed to single port agreements given that all relevant port and local health authorities are signatories.

In a bid to start cruising, a number of cruise companies have promised updated health and safety measures prior to boarding and onboard their sailings.

Luxury French line Ponant, which will resume sailings on 16 June, will require its guests and crew to be vaccinated. Before boarding, all crew and passengers will also need to show proof of a negative PCR test carried out within 72 hours of boarding the ship.

Royal Caribbean’s finance chief, Jason Liberty said in an interview that company’s surveys among customers and crew suggest most of them are willing to be vaccinated.

“We do understand for health or religious reasons or belief reasons that some people won’t want to, and that’s been in place for many years in terms of how we vaccinated for flu,” he said on a conference call.

Royal Caribbean also said it expects costs to increase as it resumes service. Booking expenses for the return of crew members to ships and implementing health and safety protocols would add to costs, according to the Wall Street Journal.

“The decision to return each vessel takes into account many variables, including deployment opportunities, commercial potential, cost of operations and cash flow,” the company said in a stament.

“Given the fluidity of return to service decisions and costs related to the ramp-up, the company cannot reasonably estimate a monthly average cash burn rate related to such ramp-up. Monthly average cash burn rate for ships that are in lay-up status is expected to remain consistent with previous expectations.

“Booking activity for the second half of 2021 is aligned with the Company’s anticipated resumption of cruising. Pricing on these bookings is higher than 2019 both including and excluding the dilutive impact of future cruise credits (FCCs).

“Cumulative advance bookings for the first half of 2022 are within historical ranges and at higher prices when compared to 2019. This was achieved with minimal sales and marketing spend which the Company believes highlights a strong long-term demand for cruising.”

Norwegian Cruise Line said it would require passengers and crew to be vaccinated at least two weeks before embarking on a ship.

The three Norwegian Cruise Line Holdings brands, also this week revealed their move to Europe in response to the CDC’s conditional sailing order.

Regent Seven Seas will be sending their flagship, the Seven Seas Splendor sailing from the UK beginning September 2021.

Oceania will be sailing the Marina in August, beginning with sailings to Scandinavia and Western Europe. Marina will resume her originally published voyage schedule, commencing on 29 August 2021 in Copenhagen.

And NCL will be restarting its operations in Europe from Barcelona and Rome to the Mediterranean and Greek Islands from 5 September 2021.

“Come September we will have the double celebration of our return to the seas as we also recommence the inaugural season of the ship that perfects luxury, Seven Seas Splendor,” said Jason Montague, president and chief executive officer, Regent Seven Seas Cruises.

The first cruise in her inaugural season has Seven Seas Splendor scheduled to set sail 11 September 2021 for an 11-night voyage, round-trip from Southampton, England, visiting Scotland, Northern Ireland and Ireland. After her initial voyage, the ship will transition to explore the beautiful Mediterranean before crossing the Atlantic to sail in the Caribbean. While many of her sailings are already sold out, there are still opportunities to cruise later in Seven Seas Splendor’s European season, and in the Caribbean in early 2022.