Opinion: Low flu transmission due to lockdown might mean less immunity

Dame Anne Johnson Dame Anne Johnson  - As Health Secretary, Sajid Javid, launches the 'UK's largest ever flu vaccine programme', Professor Dame Anne Johnson (UCL Infection & Immunity), explains why more people might be infected this year than usual, and stresses the importance of the annual flu jab. FLU is always unpredictable. It's difficult to predict because the strains that circulate change from one year to the next. Each year, an international group looks around the world to see which variants have been circulating most recently and it puts those into the vaccine so that they contain the most up-to-date strains. But if you've got low levels of flu transmission - as we did last year because of all the lockdowns - it is more difficult to make those predictions. The amount of flu also depends on how much immunity there is in the general population. Because we have had two years without many infections there may be some waning of immunity, which might mean more flu this year than usual.