British Airways passengers who are prevented from boarding an aircraft because of suspected swine flu could lose the price of their ticket.

The British carrier has confirmed that normal ticketing conditions will apply, which means that only with flexible tickets will be offered the chance to travel at an alternative date. All other ticket holders will be expected to seek reimbursement from their travel insurers.

Virgin Atlantic, which is also screening passengers for swine flu symptoms, is taking a more lenient stance, saying that if a passenger was turned away at the airport, it would try to rebook them at a later date free of charge.

But both airlines said that anyone who cancelled their trip ahead of travelling to the airport would have to rely on their insurers for reimbursement.

The Air Transport Users Council has attacked BA’s stance. A spokesperson told The Times: “It is unworkable to expect travel insurance to cover it. We would have hoped there would have been a facility to rebook.”

Airports and airlines are bracing themselves for large numbers of passengers presenting themselves at the check-in desks displaying flu symptoms.

British Airways said it will have a medical team on hand to provide advice and where necessary tell its staff to prevent the passenger boarding.

Even though the results of swab tests are required for a definitive diagnosis, which can take several days, a decision will be made on the spot.

If they are prevented from boarding, insurers would require written confirmation from a doctor that this was because of sickness.

Ryanair says it would allow passengers to rebook. Eurostar, meanwhile, said it would also allow passengers to travel on an alternative date or, in some cases, offer a refund.