Calls for people to get their annual flu vaccination have increased in the last few weeks amid warnings that flu could strike earlier this year and be much “worse than the previous two years”.

This comes as the World Health Organization predicted a surge in Covid-19 and influenza cases as winter approaches. Dr Hans Kluge, WHO’s regional director for Europe warned: “with autumn and winter approaching, we anticipate a surge in [Covid-19] cases with or without a resurgence of seasonal influenza in Europe.”

“We can’t speak with any certainty because each region and each country have its own specificities,” added Dr Catherine Smallwood, WHO Europe’s senior emergency officer. “But we have looked quite closely at the flu season in the southern hemisphere. Looking at countries such as Australia, where they saw – quite early on – a sharp increase in influenza in the season that did contribute to some pressures on health systems.”

Amid an increasing cost-of-living crisis, the Government announced last month that everyone over-50 or considered to be vulnerable will be offered a free flu jab as well as school children in years seven to nine. “When offered people need to get their winter flu jab as soon as possible, and the same for the Covid booster,” said Professor Matt Keeling, epidemiologist at Warwick University and a member of the Government’s advisory group Sage.

Professor Keeling added that Covid-19 measures including mask wearing had reduced flu in previous years. “This means that there is probably slightly less immunity in the population than in ‘normal’ years,” he said. “Although the extended vaccination programme last year will help mitigate some of this.”

Dr Smallwood warned that because of a lack of preventative measures, individuals and healthcare professionals must be more vigilant than ever. “There will likely be an interplay between the different viruses,” she said. “So, we need to be really agile in our response and be ready to respond to any changes in the virus circulation.”