Millions of people are being urged to get a flu jab by Friday to maximise protection over Christmas, as new figures reveal that more than half of those who are pregnant or have an underlying health condition have yet to be vaccinated. The UK Health Security Agency (UKHSA) is encouraging eligible people to have the vaccine by 10 December to allow it take full effect before the festive season. In particular the agency is pushing for pregnant women and those with underlying health conditions to come forward, but it is also calling on people from a black Caribbean or black African background, with data suggesting they have the lowest uptake of the vaccine. While 79% of those aged 65 and over have already come forward for their flu jab, exceeding the World Health Organization target of 75%, less than half of those who are pregnant or have underlying conditions have taken up the offer. Uptake among those under 65 in clinical risk groups is just 41.4% in England, while in pregnant women, only slightly more than one in three – 34.4% – have been vaccinated so far. Flu is a highly infectious disease and can lead to serious complications for those living with a long-term health condition, including respiratory and heart conditions, diabetes, kidney disease, liver disease or a chronic neurological disease such as multiple sclerosis or cerebral palsy. Compared with healthy adults, people with underlying health conditions are on average 11 times more likely to die if they catch flu, the UKHSA said. Pregnant women are also at increased risk of serious complications and should have the flu vaccine to help protect themselves and their babies, the agency added. “Getting your winter vaccines, whether that is your flu jab if eligible or your [Covid] booster jab, is one of the most important things people can do for yourself and your family this winter,” said Sajid Javid, the health secretary. “Don’t delay – book your flu vaccine as soon as possible.” While levels of flu infection are still low, this can typically “ramp up” over December, with a peak in January, the UKHSA said. Eligible adults can book their free NHS flu vaccination at their GP practice or local pharmacy. In England, more than 35 million people are eligible for a free flu vaccine this winter. In addition to people aged 65 and over, those with underlying health conditions, and pregnant women, children are offered the vaccine to help protect them and reduce the spread of flu to more vulnerable people. This includes children aged two and three on 31 August; and schoolchildren up to year 11. Dr Conall Watson, a consultant epidemiologist at the UKHSA, said: “The threat of flu has not gone away. It can cause serious illness and be fatal. Flu vaccination saves lives. If you are eligible, you don’t have to wait to be called up – book your flu vaccine as soon as possible to help protect yourself and family this Christmas.”