Americans have been advised not to travel to Bermuda because of the “high risk” of coronavirus infection.

The warning was issued by the US Centres for Disease Control, which said that “travellers should avoid all travel to Bermuda”.

The island is one of 175 countries that the CDC said should be avoided because of a Level 4 “very high risk” assessment.

Bermuda was earlier classed as very low risk.

The CDC website said travel to Bermuda could increase the chance of catching and spreading the coronavirus.

The change in status came after the number of active coronavirus cases in Bermuda rose from 39 on December 1 to 251 yesterday.

But the seven-day average of the real time reproduction number fell below 1.0 again to 0.87 yesterday.

An “R rate” above 1.0 is considered to be dangerous because the number of cases can expand on an exponential basis.

But the CDC’s decision was questioned by Glenn Jones, the interim CEO of the Bermuda Tourism Authority, who claimed Bermuda was “one of the safest places on the planet”.

Mr Jones said: “This is a challenging period for every destination, but few have the opportunity to differentiate like Bermuda.

“We have high-performing public-health officials with a track record of robust testing and contact-tracing that has made our island one of the safest places on the planet since the pandemic’s start.

“Protecting our community requires each of us to comply with health and safety protocols – and we put that same expectation on our visitors.

“All of these pieces working together will strengthen our CDC travel rating and bolster a safe and responsible tourism recovery.”

Lee Rizzuto, the US Consul General, blamed the change on the steep rise in the number of Covid-19 cases on the island in recent weeks.

He said: “Due to the rapid increase of cases in Bermuda, the CDC changed Bermuda’s travel health notice from their newly implemented rating system from, Level 1 – identifying Bermuda as a low risk destination – to Level 4 notice – advising travellers to avoid travel to this destination.”

Mr Rizzuto earlier this year helped Bermuda to lower its rating.

He said: “All travellers to Bermuda should follow guidelines issued by the Bermuda Government which will have a direct impact to improving case counts and CDC rating.

“It is important to note that Bermuda has recently implemented a $300 fee to all residents that travel home without a pretest which has been suspended past Christmas.”

The CDC website told Bermuda-bound travellers to get tested before departure and in advance of return to the US and to quarantine at home.

The website said: “During travel, wear a mask, stay at least six feet from people who are not travelling with you, wash your hands often or use hand sanitiser, and watch your health for signs of illness.”

The website added that foreign nationals that had been to several other countries – including the UK and most of Europe – would be refused entry to the US.

The advisory said that if people must travel:

• They should take a test one to three 3 days before travel. People should not travel if they are waiting for test results, test positive, or are sick. They should also follow entry requirements for the destination and provide any requested health information.

• Travellers should wear a mask, stay at least six feet from people who are not travelling with them, wash their hands often or use hand sanitiser, and monitor themselves for signs of illness.

• People should take a test one to three days before travel and follow destination and airline recommendations or requirements.

• They should be tested three to five days after travel and stay at home for seven days after arrival.

• If they do not get tested, it is safest to stay home for ten days.

• If people have had a known exposure to Covid-19 while travelling, they should delay travel, quarantine, get tested, and monitor their health.