Flu shots, which to get, and who should get them
Updated: Apr 15
The flu usually peaks in fall and spring. It is fall, flu season has begun, and this year's shot is out. I wanted to address a few patient questions and give a little background on vaccines and the flu.
Vaccines and alternative medicine
One of my favorite witticisms about alternative medicine is the following - “By definition, alternative medicine is medicine that has been proven not to work, or medicine that has not been proven to work. Do you know what they call alternative medicine that has been proven to work? - - - medicine.” Translation - there is no ‘alternative’ form of medicine - there is only medicine that works or medicine that does not work. Vaccination is one of many excellent examples of an idea that originally came from so called 'alternative medicine' or 'folklore medicine', and was subsequently proven to work. Now we just call it - - - medicine.
The earliest form of vaccination was called 'inoculation’. Pus was extracted from the wound of a person infected with Smallpox and transferred to the patient to be inoculated via cuts on the skin. Versions of this practice are seen in both Traditional Chinese and Ayurvedic medical texts dating back at least two millennia. It is estimated that two percent of people died from the inoculation procedure; however, it was still far safer than the 20-60% fatality rate of naturally contracted Smallpox. Inoculation became known in England 400 years ago, by way of the Ottoman Turks. A country doctor named Edward Jenner made the procedure safer. Instead of using the Smallpox virus, he used Cowpox for inoculation. Cowpox was a similar virus to Smallpox. It infected cows but caused a milder form of the disease. Jenner noted that milkmaids infected with Cowpox had an uneventful course and never contracted Smallpox. He renamed the technique - vaccination (vacca is latin for cow). Vaccination proved to be so safe and effective that Smallpox was eventually eradicated from the planet in 1980 after a worldwide campaign. Vaccination has saved hundreds of millions of lives. Now we call this ancient form of alternative medicine - 'medicine'.
The current practitioners of alternative medicine, like Chiropractors, Naturopaths, Homeopaths, and Integrative Medicine doctors, should love vaccines. They claim to be preventive, they claim to be natural, and they claim to be safe. There is nothing more preventive, natural, and safe than avoiding a future infection by stimulating your own immune system with it. Yet they make up the largest part of the group that oppose vaccination. I can't explain their reasoning. Maybe it's distrust for science? It is true that scientists and industry have behaved badly at times. I am the first to point that out. But they are throwing out the baby with the bathwater; and in this case, killing the baby - and maybe someone else's baby.
(a link to an excellent history of vaccines)
But I digress…
Cold vs flu
A cold is exceptionally common and caused by one of hundreds of cold viruses. The average person suffer 1-2 colds per year; hence the name, the common cold. Influenza is caused by the influenza virus; it is less common than the cold but much more memorable. Typically a cold involves a sore throat and runny nose. You feel bad with a cold but you could go to work if you had to. A flu is much more severe. It starts abruptly with severe body aches and high fevers up to 103 - it feels like you were run over by a truck. The sore throat and runny nose are not so bad. If you don't think you've ever had a flu in your life you probably haven't - you would remember it!
Influenza virus, mutation, and immunity
There are two main types of influenza virus: influenza A and influenza B. Influenza A is more deadly and can mutate more easily. Mutation produces new strains. It involves a change in one of the two surface proteins Hemagglutinin(H) and Neuraminidase(N) (pictured below). Flu strains are named after these two surface proteins. Hence, H1N1 (swine flu) or H5N1 (bird flu). These proteins are important because your body's immune system use them to identify and kill the influenza virus. Even though you may have been infected with the flu in the past, or were vaccinated, you are still susceptible to new strains of influenza. This is why we all require a newly formulated vaccine with each season.
The influenza virus is an example of evolution in real time. Certain mutated forms of the virus are capable of evading the immune system and live to infect another person. Mutation followed by natural selection. This makes Influenza very difficult to eradicate. On the other hand, Polio, Chicken pox, Measles, Mumps etc are not capable of significant mutation (for now), and therefore, only require one vaccine. Why haven't we eradicated these other infections? Jenny McCarthy (that was a joke - sort of)
A vaccine to cover several strains
The time to get vaccinated is in the fall when the new vaccine comes out. The 2019-2020 Influenza vaccine, this year's vaccine, was formulated from the most virulent and prevalent flu strains of the 2018-2019 season - Influenza A Brisbane(H1N1), Influenza A Kansas(H3N2), Influenza B Colorado, and Influenza B Phuket. It's only a guess; the prevalent flu this season may turn out to be a different strain(s) rendering the vaccine less effective. It takes 6 months to produce a new vaccine; thus, it would be impossible to introduce a new vaccine in the middle of the season if we get it wrong.
The number of strains covered by the vaccine is know as its valency. A trivalent vaccine contains three strains - two influenza A strains and one influenza B. A quadrivalent contains four strains - two influenza A and two influenza B.
The ultimate goal for the future is to develop a universal vaccine. A vaccine that would cover all strains. Scientists are working on this as we speak. If you are interested in following the 2019-2020 flu season, the CDC has an excellent site that maps out the prevalence of the flu throughout the country from week to week.
Fluzone, Fluad and the over 65 population
There are 30,000 deaths a year in the US that are associated with the flu. The 65 and over population accounts for over 90% of these deaths. One of the paradoxes of the flu vaccine is that it works best in younger people. People who need it the most - patients over 65 - have less responsive immune systems. Two vaccines have been FDA approved for the over 65 population to augment the immune response. Fluzone, a high dose trivalent vaccine that contains 4 times the usual dose of vaccine; and Fluad, a trivalent vaccine that adds a molecule (an adjuvant) that makes the vaccine more immunogenic. Both of these products have been shown to improve the antibody levels in blood - a surrogate marker of immunity. However, the evidence is weak that they prevent the flu or complications of the flu better than the standard dose. And they are associated with aggressive local reactions like swelling and pain at the injection site.
Therefore, at this point in time, the CDC does not recommend these new vaccines over the standard quadrivalent vaccines (and neither do I). We only carry the standard quadrivalent vaccine in our office. If you want the high dose Fluzone or Fluad you can get these at the pharmacy.
What about the mercury and preservatives?
To save on glass and plastic waste, Thimerosal, a mercury containing preservative, was added to multi-dose vials. One vial could provide 10 doses of vaccine. Thimerosal was thought to be the agent responsible for Autism by anti-vaccine advocates. Biologically, this hypothesis does not make sense. Thimerosal is less bioavailable than mercury and one dose of vaccine contains only about 50 micrograms of mercury - about the same amount of mercury in one can of tuna. Remember ’only the dose makes the poison’. However, as an example of consumer pressure and pseudoscience winning over science and reason, manufacturers removed Thimerosal from all childhood vaccines in 2001. Since then all vaccines given to children are single dose and Thimerosal free. Despite this, Autism rates continue to rise; and in addition, we are polluting the environment a little more than necessary with plastic and glass. To clarify and allay any unwarranted fears, the single dose vaccines that we carry in our office contain no Thimerosal.
Formaldehyde has also been used as a preservative in vaccines in very small concentrations. What's funny about formaldehyde being implicated in disease by anti-vaccine advocates is that the body naturally produces formaldehyde as a by-product of metabolism. In fact, the body contains 100 times the concentration of formaldehyde than found in vaccines and a sample of human blood contains about 2.5 micrograms/ml. But I don’t blame the pseudoscience world, they have never really been that good with the details.
Who should get the vaccine?
The CDC has recommended that EVERYONE OVER THE AGE OF 6 MONTHS receive the influenza vaccine. In addition, they have identified persons who are high priority for the flu shot. These people are at high risk of death and flu complications or they are in close contact with people who are:
Children aged 6 months through 4 years (59 months);
People aged 50 years and older
People with chronic pulmonary (including asthma) or cardiovascular (except isolated hypertension), renal, hepatic, neurologic, hematologic, or metabolic disorders (including diabetes mellitus)
People who are immunosuppressed due to any cause, including immunosuppression caused by medications or by human immunodeficiency virus (HIV) infection
Women who are or will be pregnant during the influenza season and women up to two weeks after delivery
People who are aged 6 months through 18 years who are receiving aspirin or salicylate-containing medications and who might be at risk for experiencing Reye syndrome after influenza virus infection
People who are residents of nursing homes and other long-term care facilities
American Indians/Alaska Natives
People with extreme obesity (body-mass index [BMI] is 40 or greater);
Health care personnel
Household contacts and caregivers of children under 5 years and adults aged 50 years and older
Household contacts and caregivers of people with medical conditions that put them at increased risk for severe illness and complications from influenza.
Who should not get the vaccine?
Patients with egg allergies were once a concern. This is because the influenza vaccine is made by culturing the virus in chicken eggs. However, the process has been refined in the last decade. There is less that 0.01 micrograms of egg protein in a single dose. Over 4,000 patients with egg allergies have received the influenza vaccine under supervision with no reaction. People with a history of Gillian-Barre syndrome should avoid influenza vaccine. Gillian-Barre syndrome is a serious neurologic disorder that causes paralysis. It has been associated with 1 in a million flu shots although causation has not been properly established. Please check out the CDC website for more info on the flu.
The vaccine is not perfect, so why get it?
In perfect conditions, when the vaccine strain matches the observed strain, the vaccine is only about 60-70% effective. In years when the vaccine strain is not matched, the vaccine is as low as 10% effective. Some of you may have contracted the flu during a season you received the flu shot. The following are 7 reasons why you should still consider the flu shot:u
You did not have an influenza infection. You can't blame the influenza vaccine for not working if it was not the influenza virus responsible for your symptoms. Only 20% of flu-like illnesses are actually caused by influenza virus.
The vaccine works better when received annually as opposed to one time. There is good data to support this cumulative effect.
The greater the number of people in the community that get vaccinated the better it works. This is known as herd immunity - a vaccination is a communal effort.
The vaccine prevents the spread of the virus in the body, not the initial infection. This is known as non-sterilizing immunity. You might still get the flu but avoid complications. Vaccination leads to a 60% reduction in hospitalizations and a 57% reduction in pneumonia.
The vaccine seems to prevent cardiovascular events. Severe infections like the flu cause an inflammatory storm and thicker blood (hypercoagulable state) leading to strokes and heart attacks.
The vaccine reduces the number of people that end up on antibiotics during cold and flu season.
You probably partake in treatments with much worse benefit to harm ratios - people use supplements, probiotics, vitamin infusions, cryotherapy, etc all with less evidence of benefits and no long term safety data.
Is the influenza vaccine perfect? No. Can you still get the flu if you get the vaccine? Yes. But I still recommend the flu shot. The more people that receive the vaccine, the more likely we can achieve herd immunity. Vaccination can help others around you, especially the frail.
The flu shot actually gave me the flu!
The flu shot is not capable of giving the flu but there are 3 reasons why it would appear to do so:
The immune system is stimulated by the flu shot and can produce mild flu-like symptoms for a day or two.
Most people confuse a cold for a flu.
The law of truly large numbers - During the cold and flu season a lot of people get sick and a lot of people get vaccinated. The likelihood that some people get sick coincidentally after a vaccination is extremely high. Especially since it takes the flu shot 2 weeks to become effective.
Is there a financial conflict of interest?
Conflict of interest is a very important factor in medicine and healthcare. One of my directives to help my patients is to expose conflict of interest in heatlhcare and remain conflict of interest free myself. Big Pharma, Big Supplement, Monsanto, Big Organic Food, Science-based medicine, and Alternative medicine are all incentivized by profit. In addition, individual practitioners are incentivized by profit
Do vaccines provide a financial conflict of interest? No. First, pharmaceutical companies are not aggressive at promoting vaccines. It is true that doctors are sometimes paid "consulting fees" for drugs like heart drugs, osteoporosis treatments, or hormones etc.; but it is rare that a doctor is on the payroll of "Big vaccine". Second, individual practitioners do not generate significant income from vaccines. Practitioners can generate substantial income from selling supplements in their office. Supplements are lucrative because they are sold at a substantial mark-up and taken on a daily basis for life. When it comes to vaccines, most practices only break even after paying for the cost of the vaccine and manpower for administration. In my practice, I pay for the vaccines out of my own pocket and do not bill your insurance to recoup costs. So each vaccine costs me money and manpower. From a financial point of view, I am actually disincentivized to offer vaccines. I do so because they are very safe and moderately effective.
How bad can a pandemic be?
The Spanish flu pandemic of 1918 starting near the end of WW1. It was an H1N1 strain, similar to the swine flu of 2009, and spread over the planet as the troops returned home from the war. The low estimate is that it killed 20 million people and the high estimate is 100 million people - more than the entire death toll of WW1. If one is to imagine some doomsday viral apocalypse, one does not have to look to exotic viruses like Ebola, Zika, Chikungunya, or Dengue. Influenza is a much likelier candidate. It easily mutates, does not require a vector like a mosquito, and can spread through an entire airplane with a single cough or sneeze. The perfect microscopic predator. It is a sobering reminder of who really has dominion over the creatures of this planet. They lived for billions of years before us and will live for billions of years after us.