Why the next FLU SEASON may be worse than ever

There have been barely any cases this winter thanks to Covid restrictions. But now experts fear this will leave us dangerously exposed...

TheRe have been few silver linings during the pandemic, but the latest data on flu infections is one of them. While Covid has been running amok over the past year — infecting four million people in the UK and taking the lives of more than 120,000 — flu has been virtually eradicated.

Latest figures from Public health england show that since the start of the year — typically the height of the flu season — not a single case of influenza has been reported by laboratories (which test patient samples sent by GPs or hospitals to determine the cause of ill health), and only five people admitted to hospitals in england had flu, compared with 90 a week last year.

Meanwhile, data from the Royal College of GPs Research and Surveillance Centre shows that the amount of flu virus circulating this year, based on the number of patients who consult GPs with symptoms, is about 95 per cent lower than normal in england.

In fact, infections have dropped from about ten cases per 100,000 people in the first two months of 2020 to less than one per 100,000 for the same point this year. Meanwhile, cold and flu remedy sales have dropped by almost half.

‘We are seeing the smallest number of influenza cases and deaths for over 100 years,’ says Dr John McCauley, director of the Worldwide Influenza Centre at the Francis Crick Institute in London.

The figures are astonishing given that, in most years in the UK, seasonal flu kills between 10,000 and 30,000 people.

yet experts say it’s not all good news — and that the fall in cases could make a spike in infections more likely next winter. What’s more, the lack of circulating flu virus could make it harder for scientists to develop an effective vaccine for next winter.

FLU, an infection caused by the influenza virus, is spread in much the same way as Covid — through tiny droplets released into the air by coughing and sneezing, or coming into contact with someone who has the virus. Symptoms include a high temperature, body aches, a cough, sore throat and exhaustion.

Most people will recover on their own. But for some, particularly the elderly and those with underlying medical conditions, flu can be deadly.

For this reason, every year the nhS offers a flu vaccination to young children — the main spreaders of flu — and at-risk groups (about 15 to 20 million people in england).

experts say the measures introduced to reduce the spread of coronavirus have also brought a drop in flu cases.

‘all the measures taken to prevent Covid transmission — social distancing, reduced physical interaction, wearing masks, hand-washing — also work against other respiratory infections such as influenza,’ says Dr andrew Preston, a reader in microbial pathogenesis at the University of Bath.

‘Given these measures have been in place during the typical flu season, cases have plummeted this year.’

another factor is the overwhelming uptake this year of the seasonal flu jab which offers, on average, 50 per cent protection against the virus.

amid concerns that if Covid and flu struck at the same time it would be disastrous both for patients and the nhS, the vaccine programme was extended to the over-50s last year.

according to Dr Vanessa Saliba, head of flu at Public health england, this year’s flu immunisation programme is ‘on track to be the most successful ever’.

‘We have had the highest levels of vaccine uptake recorded for those aged 65 and over, and two and three-year-olds and healthcare workers,’ she says.

This year more than 80 per cent of over-65s, 55 per cent of two and three-year-olds and 75 per cent of healthcare workers have had the flu jab. This compares with about 72 per cent uptake for the over-65s and 44 per cent uptake among toddlers in the 2019/2020 winter.

There may be added benefits to this. Two key studies, from the universities of Milan in Italy and Sao Paolo in Brazil, last year found that routine flu jabs could also cut the risk of developing severe Covid.

The Brazil study, involving 90,000 people, found mortality rates among Covid patients were 35 per cent lower among those who had had a flu shot.

Despite the small number of cases, those who are eligible but have not yet had the flu vaccine, are still encouraged to do so because the flu season does not normally finish until the spring.

‘Flu can be a nasty illness and the flu jab is the best protection against it,’ says Professor Martin Marshall, chair of the Royal College of GPs.

‘ The flu vaccination programme is still ongoing, and we’d encourage eligible patients to come forward. The last thing we want is to see an increase in flu cases while we continue to tackle the Covid-19 pandemic.’

HOWEVER, the dramatic drop in flu cases this year doesn’t mean flu has gone for good. When social distancing measures are eased, experts expect the flu virus to return, perhaps with a vengeance next autumn.

‘as we lift the restrictions, just as coronavirus cases will increase, we will see a rebound in respiratory conditions such as flu,’ says Dr Preston.

‘This bounce-back could be even greater than pre- Covid levels because people have not had the usual boost to their immunity from natural exposure to the flu virus, either from having had the vaccine or from coming into contact with the virus [which helps us] in developing antibodies against it.’

Dr McCauley agrees: ‘Waning immunity could give us more flu cases. That doesn’t mean they will be more severe, but we should plan to protect people with the vaccine next year.’

Meanwhile, fewer flu cases has its drawbacks for the next flu vaccine. every year scientists look at the circulating strains of influenza globally, and then predict which strains are likely to be prevalent the following year and thus which to include in the flu jab. But with so few cases this year, there is less data on which to base their decision.

The World health organisation (Who) announced last week that it was changing one of the four strains to be included in this autumn’s vaccine.

But according to Dr McCauley, who works at one of five Who centres that track flu viruses and helps to update vaccines, this year has been a challenge.

‘Flu hasn’t gone away, but in large parts of the world there are very small numbers of cases,’ he says. ‘With smaller numbers of viruses being analysed, it has been more difficult to get a general picture of which viruses are out there.’

What the pandemic has shown us is how we can drive down levels of all sorts of infections through social distancing and wearing face masks.

‘The question is whether we will want to do that in future years to prevent the spread of flu,’ says Dr McCauley.