You can’t get influenza from a flu shot – here’s how it works

June 25, 2019 6.11am AEST

Authors

1. Allen Cheng Professor in Infectious Diseases Epidemiology, Monash University
2. Katherine Kedzierska Academic, Microbiology and Immunology, University of Melbourne

Disclosure statement

Allen Cheng receives funding from the Commonwealth Government and holds research grants with the National Health and Medical Research Council. He is the Chair of the Advisory Committee for Vaccines and the Co-Chair of the Australian Technical Advisory Group on Immunisation.

Katherine Kedzierska receives funding from the National Health and Medical Research Council, and from the Australian Research Council.

Partners

Influenza is a moving target for vaccines. Each year, up to four different strains circulate, and they are constantly evolving to escape our immune system.

So rather than childhood jabs giving long lasting immunity, we need annual flu shots to provide optimal protection against influenza.

But while you might sometimes get sick after having a flu shot, it’s a myth that having a flu shot can give you the flu.

A quick history of the flu vaccine

Influenza vaccines were first developed in the 1930s and 1940s, starting with the isolation of the influenza virus.

Back then, we learned there were many different influenza strains. To be effective, early research showed the vaccine needed to be matched to the circulating strains, and to be able to stimulate a response from the immune system.

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Read more: When’s the best time to get your flu shot?

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The process to produce modern influenza vaccines now occurs on a much more refined and industrial scale. Hundreds of thousands of influenza viruses are collected by hundreds of national influenza centres around the world.

From these, four strains are selected for the annual flu vaccine, based on the viruses that are circulating at that time, how well the vaccines activate the immune system, how the strains are evolving, and the effectiveness of previous vaccines.

Most modern vaccines are manufactured by growing large quantities of live virus – mostly in chicken eggs or less commonly animal cells – which are then purified, deactivated and split into smaller components. These vaccines are inactive and cannot replicate.

There are also two new “enhanced” vaccines that are used in older people, who don’t tend to respond as strongly to vaccines: Fluzone High Dose and Fluad, which is designed to better stimulate immunity and draw immune cells to the site of vaccination.

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Read more: High-dose, immune-boosting or four-strain? A guide to flu vaccines for over-65s

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How the immune system fights the flu

The human immune system has several strategies to protect against infection. For viral infections such as influenza, the key strategy is known as adaptive immunity. This part of the immune system can “remember” previous exposure to pathogens.

When you get an influenza infection, the virus enters and hijacks the machinery of the host cell to replicate itself, before releasing these copies to infect more cells.

T lymphocyte cells of the immune system can recognise this viral incursion. T cells protect against further spread of the virus by activating pathways that cause infected cells to trigger a “suicide” process.

Another strategy the body uses is to produce antibodies, which are molecules produced by B cells that recognise components of the viral capsule. These antibodies work by sticking to the surface of the influenza virus to prevent it spreading and facilitating disposal.

Flu shots help mount a quicker defence

On a first exposure to a pathogen, our B cells take at least two weeks to ramp up production of antibodies. However, on subsequent challenges, antibody production occurs much more quickly.

Influenza vaccines harness this arm of the immune system, known as “humoral” immunity. By “practising” on viral components, vaccines allow the immune system to react more quickly and effectively when faced with the real virus.

So why do you sometimes get sick after a flu shot?

There are several reasons why you might feel a bit off after getting your flu shot.

First, your flu shot only protects you against influenza and not other respiratory illness which might causes similar cold or flu symptoms. This includes RSV (respiratory syncytial virus), which is common in late autumn and early winter.

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Read more: Sick with the flu? Here’s why you feel so bad

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Second, stimulating the immune system can result in symptoms similar to that of influenza, although much milder and short-lived. These include local inflammation (redness, pain or swelling at the site of the vaccine) and more general symptoms (fever, aches and pains, tiredness).

Third, vaccine-induced protection isn’t complete. In some years, the vaccine is not well matched to circulating strains. Usually this is due to mutations that may develop in circulating strains after the vaccine strains are selected.

The flu vaccine also doesn’t “kick in” for two weeks after vaccine administration. In some people, particularly those who are older and those who have weakened immune systems, antibody production is not as strong, and the level of protection is lower.

Despite this, studies have consistently shown that vaccinated people are less likely to get influenza or complications from the flu than those who aren’t vaccinated.

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Read more: Flu vaccine won’t definitely stop you from getting the flu, but it’s more important than you think

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A better way to protect against the flu

A problem with current vaccines is the reliance on eggs, which results in a relatively slow and labour-intensive production process.

Current work is aiming to speed up this process by using different technologies so that vaccine manufacturers can react more quickly to changes in circulating viruses.

The “holy grail” for influenza vaccines is to stimulate an effective immune response to a component of influenza that doesn’t change each year, so annual vaccination is not required.

These efforts have proved elusive so far.

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Read more: The Holy Grail of influenza research: a universal flu vaccine

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A better strategy might be to harness T cell immunity. Recent work has shown that a type of T cell, known as “killer” T cells, can recognise other parts of the influenza virus, and therefore can provide broad protection against seasonal and pandemic strains.

But while we wait for a better alternative, getting an annual flu shot is the best way to avoid the flu.

Sick with the flu? Here’s why you feel so bad

June 14, 2019 6.16am AEST You might feel terrible. But your runny nose, sore throat and aches are signs your body is fighting the flu virus. And that’s a good thing. from www.shutterstock.com

Author

1. Stephen Turner Professor, viral immunology, Monash University

Disclosure statement

Stephen Turner receives funding from the National Health and Medical Research Council of Australia, the Australian Research Council and the National Institutes of Health Centre of Excellence for Influenza Research and Surveillance.

Partners

“You never forget the flu”. This is the title of the Victorian health department’s current campaign, which highlights people’s recollections of having the flu.

Phrases include “I’ll never forget the pain of the fever”, “the flu flattened me”, “the flu knocked me out for weeks”.

This gives the impression that when you have the flu, you know you have it. What makes the flu so memorable is the severe symptoms. These include fever, aches and pains, a sore throat, runny nose, cough, and feeling weak and lethargic.

But what causes the flu? And why are the symptoms so severe?

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Read more: Health Check: how long should you stay away when you have a cold or the flu?

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What causes the flu?

Influenza is caused by a virus, a small microbe that needs to enter our cells to replicate and produce more viruses. The influenza virus infects cells that line our airways and so is easily transmitted via the spread of droplets released when we sneeze or cough.

Coughs, sneezes and the other symptoms we feel after getting the flu, are largely due to our bodies fighting the infection.

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Read more: I’ve always wondered: why is the flu virus so much worse than the common cold virus?

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The immune response is a double-edge sword

When you are infected with the flu virus, your innate immune system kicks in. Special receptors recognise unique parts of the virus, triggering an alarm system to alert our bodies that an infection is under way.

This produces a rapid but non-specific response — inflammation.

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Read more: Explainer: what is the immune system?

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Inflammation results from the action of small proteins called cytokines. A primary role of cytokines is to act locally in the lung to help limit the initial infection taking hold.

They can also make their way into the circulation, becoming systemic (widespread in the body) and act as a “call to arms” by alerting the rest of the immune system there is an infection.

Unfortunately, your body’s inflammatory response, while trying to fight your infection, results in the flu symptoms we experience.

Inflammation can trigger increased mucus production. Mucus (or phlegm) is a sticky substance that helps capture virus in the lungs and upper airways. The increased amount of mucus in the airways can trigger coughing and/or sneezing, and can lead to a runny nose. This helps expel the virus from our body before it can infect other airway cells.

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Read more: Health Check: what you need to know about mucus and phlegm

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Inflammation also results in an increase in body temperature or fever, which creates an inhospitable environment for the flu virus to replicate.

While an increased body temperature helps fight the infection, it also results in you feeling colder than usual. That’s because you feel a greater temperature difference between your body and the outside environment.

This can induce rapid muscle contractions in an effort to heat you up. This is why you can feel like you can’t stop shivering while at the same time burning up.

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Read more: Monday’s medical myth: feed a cold, starve a fever

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Finally, some of these inflammatory molecules act directly on infected cells to stop the virus replicating. They can do this by either interfering with the replication process directly, or alternatively, by actually killing the infected cell.

One of these factors is tumour necrosis factor alpha (TNF-alpha). While its actions limit where the flu virus can replicate, its side effects include fever, loss of appetite and aching joints and muscles.

Calling in the big guns

Inflammation induced by the innate response also helps alert the adaptive immune system that there is an infection.

While innate immunity provides an immediate, albeit non-specific, response to viral infection, it is the adaptive immune response that can efficiently clear the infection.

The adaptive immune system consists of specialised white blood cells called T and B cells that when activated provide a highly specific response to infection.

Activation of flu-specific T and B cells in tissues called lymph nodes results in the generation of hundreds of thousands of clones, all specific for the flu virus. These can migrate into the lungs and specifically target the virus and its ability to replicate.

This enormous expansion of T and B cell numbers in response to infection results in swelling of the lymph nodes, which you can feel under your armpits or chin, and which can become sore.

Flu-specific T cells are also a source of the inflammatory molecule TNF-alpha and help fight influenza infection by killing off virus-infected cells. Both actions can contribute to the flu symptoms.

Why can flu become a serious problem?

Our ability to see off a flu infection requires a coordinated response from both our innate and adaptive immune responses.

If our immune system function is diminished for some reason, then it can prolong infection, lead to more extensive damage to the lung and extended symptoms. This can then result in secondary bacterial infections, leading to pneumonia, hospitalisation and eventually death.

Then there are people whose immune system doesn’t work work so efficiently who are particularly susceptible to the flu and its complications. These include:

• the very young, whose immune system is still yet to mature
• the elderly, whose immune system function wanes with age
• people with other conditions where immune function might be compromised, or be taking medication that might suppress the immune system.

Preventing the flu

Washing your hands and covering your mouth when coughing and sneezing are simple things we can all do to reduce the chance of catching the flu in the first place.

And getting the flu vaccine activates your adaptive immune response to induce the sort of immunity efficient at protecting us from infection.

With the flu season well under way, prevention is our best bet that you won’t be saying “Remember the time I got the flu”.

Another one of the benefits of oestrogen to menopausal women. I have known and repeatedly told my patients that oestrogen is good for all joints, and helps to slow down the natural deterioration that occurs with age. There are other studies like this one which show the same thing. Combing oestrogen with fish oil, turmeric and cinnamon all have advantages for joints. Using them and keeping them active also slows down the onset of osteoarthritis.

Knee osteoarthritis and menopausal hormone therapy in postmenopausal women

a nationwide cross-sectional study

Jung, Jae Hyun, MD, PhD^1,2; Bang, Cho Hee, RN, MS³; Song, Gwan Gyu, MD, PhD^1,2; Kim, Cholhee, PT, MS⁴; Kim, Jae-Hoon, MD, PhD^1,2; Choi, Sung Jae, MD, PhD^1,5Menopause: June 2019 – Volume 26 – Issue 6 – p 598–602 doi: 10.1097/GME.0000000000001280 Original Articles Buy

Objective: The incidence of osteoarthritis (OA) increases after menopause, and may be related to hormonal changes in women. Estrogen deficiency is known to affect the development of OA, and menopausal hormone therapy (MHT) is suggested to be related to the development of OA. However, the relationship between knee OA and MHT remains controversial. The association between knee OA prevalence and MHT was investigated using large-scale national data.

Methods: Data were collected from 4,766 postmenopausal women from the Korea National Health and Nutrition Examination Survey (2009-2012). MHT was defined as regular hormone medication for ≥1 year, and demographic and lifestyle variables were compared between the MHT and non-MHT groups. Knee OA was defined according to symptoms and radiographic findings.

Results: In the multiple logistic regression models, the OA odds ratio was 0.70 for the MHT group (95% confidence interval 0.50-0.99), compared with the non-MHT group.

Conclusions: The prevalence of knee OA was lower in participants with MHT than in those without MHT.

Is it time to remove the cancer label from low-risk conditions?

August 13, 2018 6.13am AEST

NEWSLETTER From Dr Studd.( He is Founder and Vice-President of the National Osteoporosis Society and has been a Council Member of the Royal College of Obstetricians and Gynaecologists for 12 years and a Past-President of the Section of Obstetrics and Gynaecology at the Royal Society of Medicine. In 2005-2007 Professor Studd was Chairman of the British Menopause Society. In 2008 he was awarded the Blair Bell Gold Medal of the Royal Society of Medicine which is given every five years for the obstetrician/gynaecologist who has made the greatest lifetime contribution to the specialty. )

January 2019

Dear ‘patient’It has nearly been one year since my last newsletter which is not good enough. I do apologise because I should be in contact every six months to give you an update of what is happening in the HRT world.Last week there were some articles in the newspapers suggesting that some HRT preparations are safer than others. In particular it was singled out that oral oestrogens being associated with a slight increase of heart attacks, and deep vein thrombosis. This risk has been known for many years whether it is HRT for the menopause or the birth control pill for younger women because oral oestrogens pass through the liver where they are metabolised with the releases of hepatic coagulation factors which elevated the risk of thrombosis. Transdermal hormones do not have this effect and do not have this risk. I am sure that none of my patients reading this newsletter will ever have been prescribed oral oestrogens by me or my colleagues and that you are all having transdermal oestrogens whether in the form of gels, implants or occasionally patches.

Twenty-five years ago I founded, together with Dr Alan Dixon, the National Osteoporosis Society which has done such good work. In February this year its status will be elevated to the Royal Osteoporosis Society and we must thank our patron the Duchess of Cornwall for being such a great supporter of this cause. However, things are not so straightforward because it has essentially been taken over by bone physicians who are nervous about hormone therapy even though they would regardthemselves as endocrinologists!The NOS literature on 1osteoporosis will stress the importance of bisphosphonates (without mentioning their awful side-effects) and Strontium which similar bad side-effects or parathormone an eighteen-month course at enormous expense. But down on the list there is a paragraph on HRT which is associated with the risk of breast cancer, strokes and heart attacks. Given this false information any woman would choose an alternative to HRT. Happily, those risks are untrue but are the product of the totally flawed 2004 Women’s Health Initiative which used the wrong patients, the wrong age group, using the wrong hormones, the wrong dose administered in the wrong route.

As I have mentioned in previous newsletters the authors of this NIH funded work costing one billion dollars and still counting have mostly disassociated themselves with the conclusions. Several are lecturing all over the world apologising for their part in this academic scandal and the damaging effect that it has had on millions of women. In this study they used oral not transdermal oestrogens, the patients were obese, hypertensive, diabetic, and the conclusions revealed at a press conference before many of the co-authors had even seen the finished paper and certainly many days before we were able to read it in scientific journals and analyses the data and conclusions.The NOS has just had their three-day international conference with not one lecture on hormones. Nor was there a single company that makes hormones in the exhibition room.The program consisted of life-style choices, exercise, weight bearing exercises, prevention of falling and of course a discussion of every non-hormone medication available.This is so disappointing as the most effective and safest way to treat and prevent osteoporosis is to give many years of transdermal oestrogens which also will have a beneficial effect upon mood, on sleep, libido with a decrease in heart attacks, stroke probably Alzheimer’s and yes, no increase in breast cancer.

I have been fighting this fight for all of twenty-five years but there is still a long way to go before physicians who fear HRT recognise that this is the safest and most effective way of preventing 2osteoporosis and treating low bone density. This is regardless of age. Young women with premature menopause or anorexia usually have low bone density and need this therapy. Women at the time of the menopause, if found to have low bone density, need this therapy and certainly women over the age of sixty-five, with demonstrable low bone density by bone density scans, need transdermal oestrogens for many, many years.

We have dozens of patients in their eighties and the oldest is a spritely ninety-five-year-old who travels from foreign lands to see us for her six-monthly implant of oestradiol and testosterone.Apart from the obvious value for menopausal symptoms and low bone density the place in the treatment of various “psychiatric” problems needs further study before more women are messed up with inappropriate antidepressant or anti-psychotic medication. The role of oestrogens, testosterone and progesterone in the causation of menopausal, postnatal and premenopausal depression are recognised by all – even psychiatrists but they have not taken the next logical step of treatment by hormones. This is the next huge challenge.Currently virtually all psychiatrists use antidepressants for these conditions, changing or adding different medication with rarely any benefit but they produce weight gain and loss of libido which only adds to the despair. The cyclical depression, anxiety and headaches of PMS or PMDD are often misdiagnosed as bipolar disorder with personality problems. These are almost invariably cured with transdermal oestrogen gels or implants but the psychiatric option is for antidepressants, lithium or worse ECT.

It is one of the medical scandals of the age as psychiatrists will not consider treating depression in women with oestrogen, bone physicians and rheumatologists will not treat osteopenia and osteoporosis with oestrogens, neurologists do not treat cyclical menstrual migraine with oestrogens, sleep experts aware that hot flushes night sweats and panic attacks are treatable with oestrogens are effective for these symptoms fail to progress to solving the problem with HRT. Perhaps we need the help of articulate “celebs” who can deliver this message to the neglected victims of this ignorance. I have Carol Vorderman’s permission to briefly tell her story which she has told herself many times on TV and radio. After a happy life and successful career she fell apart with profound depression at the age of 55. By then it had been a problem for 6 months. Before that she was well with no hint of depression – now she had suicidal thoughts. She started transdermal estradiol and the depression vanished after 2 days and hasn’t returned during the 3 years of oestrogen and testosterone therapy. She never wants to stop. Now she is determined to inform the public who can then approach their GPs with the story and evidence from my web site and suggest – no demand – that the doctor at least considers the use of transdermal oestrogen rather than the easy but usually ineffective prescription of antidepressants.

Over the last 30 years I have created a unique clinic which specialises in studying the value of hormone therapy particularly oestrogen, testosterone and progesterone. This relates of course to the menopause and the massive problem of osteoporotic fractures in all the women as well as the use of these hormones in the frequent problems of depression, anxiety, insomnia and loss of libido which is so common in women in this age group. This interest has been supported by a great deal of original research when I was at Kings College Hospital and Chelsea and Westminster hospital. Details of this research can be found on my website. This website contains information which can be printed off and given to your general practitioner and your psychiatrist (but they won’t listen).I have been fortunate to have the support in the clinic of two of my former research fellows: Michael Savvas who is now the senior consultant at Kings College Hospital and Neale Watson who is a senior gynaecologist at Hillingdon Hospital. They are experts and very well informed about the effects of hormones in the causation of the problems in women and equally knowledgable about the best way of correcting these disorders. They have been a great help to me over the last three years in the practice and are becoming very popular with patients. I will probably reduce my work to two day’s work a week but it is time for me to move on and spend more time writing and fighting shrinks. I will always be contactable and frequently in Wimpole St but please stick around with my two partners if I am not always available because you will find no better advice on hormone therapy anywhere in the country.With best wishes

John STUDD, DSc, MD, FRCOG Professor of Gynaecology

Clin Radiol. 2018 Apr;73(4):372-380. doi: 10.1016/j.crad.2017.09.016. Epub 2017 Nov 23.

How do we manage overdiagnosis/overtreatment in breast screening?

Wallis MG¹.

Author information

Abstract

Overdiagnosis is the inevitable flip side of early detection resulting in unnecessary labelling of well women with a diagnosis of cancer and possible unnecessary treatment. Overdiagnosis occurs because breast cancers have different rates of growth and slow-growing cancers are preferentially detected by screening. Some of these slow-growing screen-detected cancers may never have been clinically apparent during an individual’s lifetime. Evaluating the benefits and risks of screening are complex, but this has been performed for the UK population by an independent review led by Professor Marmot. It might be possible to limit overdiagnosis by identifying women with “low-risk disease” earlier, either at the point of screening when additional investigations could be delayed (possibly for ever) so that they are not subjected to additional diagnostic tests, or at the point of diagnosis. Both these options would require major re-education of clinicians and the public who would need to accept that screening is “deliberately ignoring a cancer”. There is a long surgical history of reducing the burden of treatment, which continues today with trials of management of the axilla and reducing or even omitting radiotherapy for low-risk disease. The Low Risk Ductal Carcinoma In Situ trial (LORIS) has started to identify a group of breast cancer patients who could avoid surgery and be offered active monitoring. We need to consider planning a similar trial for low-risk invasive breast cancer.