Health officials are scrambling to contact more than 200 British holidaymakers on a flight from Crete last week after authorities failed to alert the airline that eight passengers had tested positive for coronavirus. The teenagers, from Hampshire, were diagnosed after returning to the UK on a Wizz Air flight to London Luton airport on 25 August. The positive tests should have triggered an urgent response to track down the other 204 passengers on board, but Wizz Air said it had not been made aware of the cases until contacted by the Guardian. The new cluster of cases from a Greek island raises further questions about the UK’s monitoring of holidaymakers, as ministers continue to rule out testing at airports. It will increase the pressure on the government to impose quarantine measures in all regions on arrivals from Greece, after Scotland and Wales announced restrictions on 1 September. The UK has pledged to quarantine arrivals from any country recording at least 20 coronavirus cases per 100,000 people over a seven-day period. On Wednesday, Greece had 14.3 cases per 100,000 people. Ben Pearce, 18, said he was one of 15 friends who tested positive for coronavirus after returning to the UK from Crete last week. At least eight of the group were on the same Wizz Air flight 8168 from Heraklion, which landed at London-Luton on 4.35pm on 25 August. Pearce said NHS test and trace call handlers had contacted him multiple times since Friday but none had asked for his flight details. “Even though I’ve filled out my details on three separate phone calls, they always seem to say I’ve got nothing on my file,” he said. “The phone calls never seem to serve any purpose other than they [the call handler] have been told they need to call you.” Pearce said he and his friends had filled out passenger locator forms (PLFs) providing their contact details, as well as the flight number and arrival time, but had not been checked on arrival at London-Luton airport. “In Greece they were checking the PLFs a lot more thoroughly, but not in England. At Luton they weren’t very on it,” he said. The Guardian revealed last week that Border Force officials aim to spot-check only 30% of returning passengers’ PLFs, which are crucial to test and trace. Damian Stafford, 52, whose 18-year-old son was among the teenagers who tested positive, said he had not been contacted by the NHS test-and-trace system. “It just seemed like a shocking lack of response really,” he said. The group, from Winchester, is the first known cluster of cases to have returned from Crete. It follows at least seven clusters, totalling at least 41 people, to have tested positive after returning from the island of Zante. The UK’s biggest tour operator, Tui, is suspending its holidays in the Zante resort of Laganas. Wizz Air said: “Wizz Air was not made aware that eight passengers who travelled on the 8168 flight from Heraklion to London-Luton on 25 August had since tested positive for Covid-19. “The airline has now informed the relevant health authorities in England who are responsible for contacting and advising the 204 other passengers. Wizz Air operates all flights in compliance with local travel regulations, and the safety of passengers and staff is the No 1 priority.” The Winchester group went for a test after friends in Crete said they had tested positive. Stafford, the owner of an IT company, said he had still not been contacted and told to isolate by NHS test and trace nearly a week after his son’s positive test. The programme aims to contact 80% of infected people and 80% of their close contacts within 48 hours, but has missed its headline target for nine weeks running. Its target is especially important when tracing arrivals from overseas because, unlike other countries, the UK does not routinely test returning travellers. The aviation industry has for months urged ministers to implement testing at airports, so that people who are negative do not have to quarantine for 14 days when returning from certain countries. Wales has said it would introduce testing at airports but ministers in London have held out, saying it is logistically difficult and risks missing some cases. Stafford said the teenagers had taken a test “entirely on their own initiative. There was nothing from the airline or the government, local or national, to tell them that they needed to go and get tested.” He said he had initially been unable to order home tests for his family using the government website: “I was told repeatedly online that there were no home tests available for at least 36 hours over Friday and Saturday.” For nearly two weeks people have complained about being unable to order a home testing kit or being directed to a testing centre 100 miles or more from their home. The government has said it has paused online booking in periods of high demand but that there was no shortage of tests. Simon Bryant, Hampshire county council’s director of public health, said: “While there’s no cause for the community to be concerned, it’s absolutely critical that anyone returning from countries on the quarantine list self isolates for the full 14 days to ensure they minimise the risk of passing on the virus.” The Department of Health and Social Care said action had been taken to advise those who needed to self-isolate to do so. It said the NHS test and trace system was working and targeting testing capacity in areas that needed it most, adding: “There is a high demand for tests, but more appointments and home testing kits are available every day and we are increasing capacity to 500,000 tests a day by the end of October. “Anyone with symptoms across the UK should get a test as soon as possible as well as washing hands regularly, wearing face coverings and following social distancing rules to stop the spread of the virus.”