Surging Covid-19 cases are a potential disaster facing the NHS this winter, but there’s another that health chiefs have been braced for since summer.
Flu, a common respiratory disease that can infect about 400 Britons each week at a winter hospital, would be expected to cause chaos for the NHS.
That fear was stoked in July after a report by the Academy of Medical Sciences warned that up to 60,000 people may die from flu this year – up from a usual average of between 10,000 to 25,000 a year, and equal to a third of the UK’s total deaths from Covid so far.
Public Health England data from August showed that the death risk for those who had both flu and Covid was nearly doubled.
A strikingly low level of flu was recorded last year. That means that the number of people who have developed immunity to it is a factor in their exceptionally high predicted case count.
Flu is a respiratory illness that affects about 400 Britons per week in winter hospitals. The NHS was expecting to be unable to cope with the strain, as Covid remains. But as we approach the end of December, that supposedly insurmountable wave of flu is nowhere to be seen (stock photo)
Sunday’s Mail featured the unusual case of disappearing flu in October 2020. It was attributed largely to lockdowns and social-distancing.
And so the biggest flu vaccination programme in British history was launched in September this year – the NHS offered the jab to a record-breaking 35 million people in England, including all teenagers and contacts of vulnerable people.
We are approaching the end of December and that seemingly insurmountable flu epidemic isn’t even visible.
The UK Health Security Agency, now called Public Health England, has revealed that the number of cases in the last week was four times less than those for the same week in 2019. There were only three cases per 100,000.
It is about half the rate of 7.6 cases per 100 000 in 2018.
The number of Google searches involving the term ‘flu’ – known to be an accurate indicator of infection levels in the UK population – are nearly 20 times lower than searches in the winter of 2019.
Experts agree that this year’s flu outbreak in the UK, despite earlier grim predictions, is unlikely. What is the cause of flu disappearing? Our mammoth flu jab program is the most plausible explanation.
According to the MoS, top geriatric physicians have reported that there is ‘only’ one case of the virus and they are seeing “little” signs in hospitals.
The same phenomenon is being observed in other parts of the world. Australia and New Zealand have very low flu numbers, as they have their flu season in the summer.
Australia had six confirmed cases from the beginning to the end of 2011. Japan and China both recorded only four.
Australia’s Department of Health reported that there were no flu-related deaths. It also stated that the prevalence of flu-like symptoms was low at historical levels.
According to the World Health Organisation (WHO), the latest global flu data “remains well below the levels observed in prior seasons”.
Experts claim that the possibility of a pandemic this winter is not likely despite earlier dire predictions.
Professor Dr David Strain is a senior lecturer at University of Exeter Medical School. He also consults in older medicine. However, I haven’t seen any. It is not likely that flu will be a big problem in this year’s epidemic.
Nationwide polls taken in September found that 89 per cent of Britons said they were still wearing a mask when they left the house most days – down from 98 per cent in May (stock photo)
Influenza can be an acute respiratory virus infection. This causes severe symptoms such as fever, headache, muscle pain and runny nasal.
Although flu can make you feel sick for several days, most people will only experience symptoms for the first few days. For hundreds of thousands, especially those who are elderly or have weakened immune systems, it can lead to death.
New data has shown that flu and pneumonia death rates are now half of what they were in the pre-Covid years.
Theories offered last year – that lockdowns meant no one could catch flu but it would emerge in force as soon as we could mix again – can no longer offer the full explanation today.
Where has the flu gone?
Our mammoth flu vaccination campaign is the most plausible explanation. 80% of seniors took up the jab offer.
Experts say that this is just one piece of the puzzle.
According to the NHS, the flu jab prevents only about half of cases – and is known to be less effective in older age groups.
The jab’s effectiveness against specific strains that are likely to hit British shores is also tweaked each year prior to the rollout. This year however, the strains have been difficult to pinpoint because they are not found at high levels worldwide.
Julian Tang, University of Leicester clinical virologist, said that “the flu vaccine is not as effective as other vaccines such Covid-19 jabs.”
The ‘Flu virus can mutate, so it is possible that the vaccine administered to final patients may not be the right match for the current virus. This vaccine is superior to nothing, particularly in older or more vulnerable people. This will not be the case with current rates that are relatively high.
Covid-19 (or the vaccine which protects against it) is one of the most fascinating theories. It may be possible that the vaccine that also prevents flu could help to guard against this infection.
The same is thought to work the other way round – having a flu jab also boosts immunity against Covid.
If the body becomes infected by any virus or has been given a vaccine to recognize it, its immune system activates and wakes up to fight the infection.
Flu-specific immune cells (or antibodies) that have either been infected with the flu or received a vaccination are the most efficient at finding the virus. They quickly alert other cells of an intruder and can be used to detect it.
But another key line of defence are fighter cells – called T cells – which are released after a jab or infection, and are not as specific in their response.
Dr Strain says that antibodies can be used to spot specific illnesses and prevent them from spreading. T cells, on the other hand, are like machine guns, which offer greater protection against virus infections.
“If someone has an active T cell response, they have a lower chance of getting infected by something else.”
In the US, striking evidence showed that those who have had their flu vaccination were 25% less likely than others to get Covid-19. People who were infected with the disease had a lower likelihood of needing ventilation or hospitalization.
Scientists, who published their findings in American Journal Of Infection Control concluded that the pattern might be caused by a strong immune response to flu vaccine.
And it’s not just antibodies and T cells: exposure to a virus or its vaccine can also ramp up another type of specialised cell – macrophages, which are particularly effective for fighting respiratory viruses.
Professor James Stewart from the University of Liverpool, who is Chair of Molecular Virology, explains that macrophages destroy bacteria and clear the lungs of dead viruses.
“This can be helpful for both the flu and Covid-19. The immune system is stimulated by both flu and Covid-19, so people can get protection from both.
Covid-19 can be protected by flu, but it’s more likely that the reverse is true. Covid simply means that other viruses are being pushed aside by Covid.
Covid-19 as well as influenza can be spread via droplets landing on noses or mouths. People can transfer these droplets to their eyes and nose by touching surfaces.
However, Covid-19 can be more infectious than the flu.
Studies show that Covid-19 is also airborne – meaning it can spread via microscopic particles that linger in the air. Although flu can also spread in this manner, it is rare.
Flu can often be treated quickly and effectively. We know that at least three quarters of all cases of Covid-19 do not have symptoms.
For the Omicron variant of Covid-19, the R number that indicates the transmissibility of the virus is estimated to be five – meaning that, on average, every person who gets it passes it to five others. The R number for flu is usually around 1.4.
It is still uncertain how long cross-viral immunity lasts. Professor Stewart says that the current evidence suggests that cross-viral protection lasts for approximately a month.
Experts are unanimous in their belief that widespread changes in behavior over the past 2 years is another crucial aspect.
While the social-distancing rules have been relaxed, it is clear that Britons still remain cautious about social interaction and they adhere to infection-control precautions, which protect them against flu.
Nationwide polls taken in September found that 89 per cent of Britons said they were still wearing a mask when they left the house most days – down from 98 per cent in May.
In autumn, another survey found that about half of those polled worked from home at the least part of the day, up from a mere third pre-pandemic.
Experts say the travel restrictions – which persisted after ‘freedom day’ in July – also played a role.
John McCauley (Director of the Worldwide Influenza Centre at Francis Crick Institute London) says, ‘International travel isn’t back to the level it was prior to the pandemic. This is certain to have helped the flu from spreading across the globe.
The International Air Transport Association reports that people fly half the amount they did in March 2020. Experts believe this partially explains Australia’s astonishingly low flu rates. Australia has been almost entirely closed to immigration for the majority of 2021.
A tragic factor in limiting this year’s hospital flu admissions could be that a significant proportion of people most likely to fall severely ill from contracting flu – the elderly and those with other serious health problems – have not survived Covid-19.
This is Dr Strain’s belief.
‘Those likely to need hospital care for flu are more likely to be older and vulnerable – and sadly many have not survived the pandemic,’ he says.
Experts warn that despite the positive outlook for flu symptoms, there is no way to be complacent.
Simon de Lusignan is Professor of Primary Care and Clinical Informatics, University of Oxford, and Director of the Royal College of GPs Research and Surveillance Centre. He said: “It’s far too soon to predict what will happen in the winter.” The flu season tends to peak in January or March.
Professor Stewart added: “The flu vaccine provides the best protection available, so anyone who is eligible should make sure that they get it.”
Flu numbers in Britain are continuing to decline, but a bird-borne version of the disease is increasing rapidly. Last week, local public health officials issued warnings, telling citizens to beware of touching live – or dead – birds.
According to Professor Ian Brown (Head of Virology, Animal and Plant Health Agency, Surrey), the UK’s avian flu levels are at their highest level ever recorded.
According to him, “The spread of the disease is expected to increase, depending on how strict keepers apply preventive measures,”
A total of half a billion birds have been killed so far.
Avian influenza is part of the same virus group that causes flu in humans. Although avian and human flu strains can be quite different, they both have the potential to infect people.
Professor Paul Wigley of University of Liverpool, Professor of Avian Infection and immunity, explains, “Migratory wild bird may transmit the virus via both respiratory secretions and stool, which could cause soil infection.”
Infected humans can lead to high mortality rates, more than half dying.
The avian strain circulating is H5N1 – which, between 2003 and 2018, led to 454 deaths out of 860 reported cases around the world.
But scientists say that so far it isn’t anything to worry about – for humans, at least.
According to the UK Health Security Agency, avian flu is mostly a bird disease with very little risk for the general public.
Prof Stewart said, “While birds can sometimes catch it in humans, it’s not transmitted from person to person.”
“And it appears to have become less transmissible from birds to humans over the last few years.”
“So, except for those who have come in contact with infected bird eggs, there is no risk to human health and therefore we don’t feel too concerned.”