UCL News


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

8 October 2021

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.

Professor Dame Anne Johnson

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.

As restrictions have relaxed, people are in contact with each other more and, despite the vaccine campaign, we are seeing continued high levels of COVID-19 transmission.

It's causing much lower levels of illness but we have still got the challenge of COVID-19, with most recent estimates of one in 85 people currently infected.

The NHS is also currently under a lot of stress with a big backlog of patients and in the winter months we always see additional pressures. It has always been a challenge to get high flu vaccine uptake, but it was much better last year.

We also welcome the extension of eligibility for the flu jab to new groups this year, including more schoolchildren.

At the moment there's little flu activity. But we have to be cautious and see what emerges in the coming months.

That will depend on several things including the uptake of flu jabs and continuing precautions people might be taking for COVID-19 - hand washing, mask wearing, self-isolation when you're ill - which also protect us from flu.

All those things will help take pressure off the NHS, which desperately needs to catch up with the backlog of patients.

This article was originally published in the Express on Friday 8 October, 2021



  • Professor Dame Anne Johnson