PREGNANT women who opt for the alternative swine flu vaccine Celvapan are now being given letters to show to medics in the hope of avoiding any more mix-ups.

The change in procedure comes after mother-to-be Annaleaze Wilkinson-Light was mistakenly injected with the Pandemrix vaccine at the Boscombe and Springbourne Health Centre.

Miss Wilkinson-Light, of Oakdale, Poole, had turned down the single-dose Pandemrix because she was concerned that thiomersal – a mercury-based preservative used in the vaccine – could damage her unborn child.

Instead, she chose to have the mercury-free Celvapan, which was originally stocked by the government for people who are allergic to eggs. But when she saw the doctor at Boscombe, she was given the single-jab Pandemrix.

Miss Wilkinson-Light, who complained to NHS Bournemouth and Poole, said the incident had been blamed on a breakdown in communication.

“At the end of the day, they can’t do anything about it now, but it should never have happened in the first place,” she said.

The primary care trust is now giving a letter to people who want Celvapan so they can take it to their flu jab appointment.

But Dr Sue Bennett, director of the Dorset and Somerset Health Protection Unit, said: “We’d like to assure pregnant women that the Pandemrix is perfectly safe and gives protection in a single dose.

“Concerns over its safety are due to confusion about the type of mercury contained in it. The vaccine does not contain the type of mercury pregnant women are advised to avoid – methylmercury.

“This vaccine contains a completely different substance, thiomersal, which has been the subject of extensive studies and has been used safely in vaccines for more than 60 years.”