The Government has urged holidaymakers to “keep an eye out” for changes to the travel quarantine list, amid increasing speculation Croatia could be included after a rise in coronavirus cases.

The Department for Transport (DfT) said an announcement could be made this week about changes to the UK’s list of safe travel corridors, with people returning from countries not included required to self-isolate for 14 days.

A significant increase in Covid-19 infections across Croatia in recent days means it may follow France in being removed from the safe travel list.

The number of cases per 100,000 people in Croatia has reportedly risen above 20, which is seen as a key benchmark.

A DfT spokesman declined to comment on Croatia, but told the PA news agency travellers should be aware the safe travel list could change this week.

In other coronavirus developments:

– Figures from NHS Digital show the overall NHS sickness and absence rate for England was the highest in more than a decade during the peak period of coronavirus. Around 2.3 million full-time equivalent (FTE) days of work across all staff groups in the NHS were lost out of a total of nearly 36.6 million in April.

– NHS Test and Trace figures show the number of in-person tests meeting the 24-hour turnaround time fell to 60.5% from 70.3% in the previous week.

– The latest Test and Trace app trial, launched on the Isle of Wight and among volunteer responders last week, is due to begin in the London Borough of Newham on Friday. Meanwhile it is understood Test and Trace chief and Tory peer Baroness Dido Harding, who was named as interim leader of the Government’s new National Institute for Health Protection earlier this week, will not apply to head up the new organisation permanently.

– It emerged, having first been reported by Civil Service World, that American giant McKinsey was paid more than half a million pounds for a 40-day consulting contract to advise the Government on the “vision” for a new test and trace body.

– Professor Sir John Bell, regius professor of medicine at the University of Oxford, warned of a “really bumpy” winter on the way, saying he believes there will be a second wave.

– Birmingham could be placed on the national coronavirus watchlist following an increase in the number of cases, although the Birmingham Mail reported director of public health Justin Varney saying he expected it to be classed as an “area of enhanced support” rather than one requiring a lockdown like Leicester or Greater Manchester.

Amid speculation Croatia may be removed from the safe travel list, the World Health Organisation (WHO) has said the Balkans region is considered a “hotspot” for coronavirus.

Dr Catherine Smallwood told a WHO press conference: “The situation in the Balkans has been a concern of ours since early June when we started to see cases increase and it’s been very much a sub-regional hotspot over the summer period.

“We really need communities to take this on board, take the adequate steps both at a country level, in terms of the basic contact tracing, case identification and isolation and testing the systems that need to be in place.

“And then where there are hotspots and increased transmission, additional targeted measures need to be brought in place very quickly to nip transmission in the bud, stop it from spreading and keep the level of transmission at controllable levels.”

The Foreign and Commonwealth Office also said travellers should “keep tabs” on any DfT announcements regarding travel corridors.

A spokesman said: “We are monitoring the international situation very closely and keeping our travel advice under constant review so that it reflects our latest assessment of risks to British people.

“Anyone wanting our latest travel advice updates can sign up to alerts on the FCO website or follow our Travel Advice social media accounts.”