Blood donors are being urged to come forward in the run-up to the festive season as blood stocks run low.
November through to the new year is traditionally a “challenging” time for blood stocks, NHS Blood and Transplant (NHS BT) said.
Christmas shopping, the party season and extra public holidays mean that some donors forget to take the time to give blood, officials said.
During the same period, hospitals in England and north Wales will need half a million units of blood, the organisation said as it launched its latest appeal.
The new radio and TV adverts feature children discussing what they want for Christmas, with one demanding talking popcorn and another requesting nine million dollars.
But the jovial scenes turn sombre when bed-ridden Alexis Wallace, five, from Gypsy Hill, south London, is asked what she wants for Christmas.
“The doctor says I need some blood to make me feel better,” she says.
The youngster, who suffers from sickle cell anaemia, is a patient at Evelina Children’s Hospital in London.
NHS BT hopes the advert will remind people to give the “ultimate gift”.
Alexis’s mother Clare said: “You wouldn’t forget to get your kids or members of your family a present so please don’t forget to donate blood - you never know when someone you love might need it.
“My daughter, and other sick children like her, need blood to stay alive or to be well enough to enjoy Christmas. So please, if you can, donate blood or platelets now or in the next few weeks.”
Jon Latham, assistant director of marketing at NHS BT, said: “This is an extremely challenging time of year for us as we need to make sure that hospitals are supplied with the blood and platelets they need to treat patients over the Christmas holidays.
“So while people are in a generous frame of mind, we’re asking that they don’t forget those whose must-have gift is blood or platelets. Donating doesn’t cost a penny and saves lives, meaning many more children and adults can spend precious time with their families over Christmas.”
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