A March 2020 newsletter for McLaren Health Plan members in the state of Michigan contains a full-page promotion for influenza vaccines. Headlined “It’s Not Too Late to Get a Flu Shot” and citing the Michigan Department of Health and Human Services as its source, McLaren makes the following claims explicitly or implicitly:
- Everyone aged 6 months and older should get a flu shot, including pregnant women.
- Getting a flu shot “is the best way to prevent against getting the flu.”
- Flu shots reduce the risk of complications from influenza in children, adults, and the elderly.
- Influenza vaccines confer herd immunity by preventing transmission of the virus and thereby protecting children younger than six months old, who are too young to get the flu shot.
- If you get a flu shot, it will build your immunity to prevent the flu.
- “You cannot get the flu by getting a flu shot.”
The implicit overall message of McLaren’s flu shot promotion is that the vaccine has been scientifically proven to be both very safe and highly effective. But every one of those claims is false or, at best, highly misleading.
Influenza Vaccination of Children, Including Infants
A 2018 systematic review of the scientific literature on the use of flu shots in healthy children published in the Cochrane Database of Systematic Reviews found with high certainty that vaccination reduces the risk of influenza illness such that five children are required to be vaccinated in order to prevent one case of the flu.
However, for children under six years of age, the vaccine “does not provide significant protection against influenza”. For children aged two years or younger, “there is very limited evidence to determine their effects compared with placebo.” For children under age two, “there is no evidence of effect”.
Furthermore, researchers found “no convincing evidence that vaccines can reduce mortality, hospital admissions, serious complications, or community transmission of influenza.”
Concerningly, data on adverse events “were not well described in the available studies”, and for children under two years of age, there were “very few randomized controlled trials”. Researchers were “surprised to find only one safety study of inactivated vaccine in children under 2 years, carried out nearly 30 years ago”. The lack of safety data for flu shots in younger children “is particularly surprising given that the inactive vaccine is now recommended for healthy children six months and older”.
There is also uncertainty about the effects of repeated annual vaccination across different flu seasons, and most studies were not well designed or conducted; the general methodological quality of included studies was judged to be “poor”.
A prior Cochrane review, published in 2012, had reached similar conclusions. Researchers had similarly expressed alarm about the lack of studies demonstrating safety in children under two years of age, remarking that, “If immunization in children is to be recommended as a public health policy, large-scale studies assessing important outcomes, and directly comparing vaccine types are urgently required.”
As their updated 2018 review indicates, such “urgently required” safety studies were not forthcoming.
Influenza Vaccination of Adults, Including Pregnant Women
A 2018 Cochrane systematic review on the use of flu shots in healthy adults found that vaccination has only a “modest” impact, requiring seventy-one adults to be vaccinated in order for one to see a benefit, and the effects on working days lost or serious complications remain uncertain.
Data for the safety and effectiveness of vaccinating pregnant women came almost entirely from observational studies. Researchers noted that vaccination with the monovalent 2009 pandemic influenza A(H1N1) flu shot was possibly associated with a higher risk of miscarriage, congenital malformation, and neonatal death.
They identified only one randomized controlled trial assessing the effects of vaccinating pregnant women. It found that a trivalent flu shot containing a 2009 pandemic influenza A(H1N1) antigen component “was weakly protective against influenza”, with fifty-five pregnant women needing to be vaccinated in order for one to receive a benefit.
That trial found no statistically significant increased risk of adverse birth outcomes. However, it involved 2,116 black African pregnant women from a single township in South Africa and assessed an influenza vaccine not licensed by the Food and Drug Administration (FDA) for use in the US, and thus its findings cannot be generalized to the US population.
Furthermore, the US Centers for Disease Control and Prevention (CDC) recommends vaccination during any trimester, but this study excluded women in early pregnancy and therefore provides no evidence that this practice is safe.
In light of this exclusion criteria, it’s worth noting that the study was funded by the Gates Foundation and included authors with financial ties to influenza vaccine manufacturers, including the lead author, who had financial ties to the manufacturer of the vaccine used in the study.
Manufacturers of influenza vaccines licensed for use in the US note in their package inserts that there is an absence of evidence from randomized, placebo-controlled trials that it is safe and effective to vaccinate pregnant women. GlaxoSmithKline’s Fluarix insert, for example, warns that “Safety and effectiveness of FLUARIX have not been established in pregnant women or nursing mothers.” There are “no adequate and well-controlled studies in pregnant women.”
While manufacturers of vaccines recommended for routine use in children have broad legal immunity against vaccine injury lawsuits, they can still be sued if injury results from failure to manufacture the vaccine according to specifications or failure to adequately disclose the risks in their package inserts as required by federal regulations. Were the manufacturers themselves to make the same claims about their products’ safety and effectiveness in pregnant women that the CDC makes, they could be sued for fraud.
A CDC-funded study by CDC researchers published in the journal Vaccine in 2017 found that women who received a flu shot containing a 2009 pandemic H1N1 (pH1N1) antigen component and who had received a pH1N1-containing flu shot the prior season had a statistically significant 7.7 times higher risk of miscarriage.
Multi-dose vials of influenza vaccine also contain thimerosal, which is about half ethylmercury by weight. Ethylmercury is a known neurotoxin that can be transported from the injection site to other organs, including into the brain, where it accumulates. In also crosses the placental barrier. Yet the CDC does not advise pregnant women to get the single-dose version in order to avoid unnecessarily exposing their vulnerable developing fetus to the neurotoxic effects of mercury. Instead, the CDC insists that the mercury in flu shots is safe despite its own cited studies acknowledging it as a known neurotoxin that crosses both the blood-brain and placental barriers and accumulates in the brain.
The Cochrane researchers also observed in their 2018 review that “industry funding is associated with optimistic conclusions” and conclusions favorable to flu shots “were associated with a higher risk of bias”, such as authors who “made claims and drew conclusions that were unsupported by the data they presented.” But even without industry funding, the quality of most influenza vaccine studies “is low”.
A prior Cochrane review, published in 2010, found that in an average year, when the vaccine antigen components are not well matched to the circulating strains of influenza, one hundred healthy adults need to be vaccinated in order to prevent a single case of the flu. Researchers found “no effect” on hospitalization and “no evidence that vaccines prevent viral transmission or complications.”
They also found insufficient evidence of safety, noting that “The harms dataset from randomized studies is small. The trial authors appear to regard harms as less important than effectiveness assessment.”
What little benefits that the data indicated are conferred by flu shots, they warned, should also be interpreted in light of the “evidence of widespread manipulation of conclusions and spurious notoriety of the studies.” Even studies not biased by industry funding were of “low” quality.
The CDC, too, researchers noted, had misrepresented the science in order to support its policy recommendations. “The CDC authors”, they observed, “clearly do not weight interpretation by quality of the evidence, but quote anything that supports their theory.”
Contrary to the CDC’s universal flu shot recommendation, the data “seem to discourage the utilization of vaccination against influenza in healthy adults as a routine public health measure.”
Influenza Vaccination of the Elderly
A 2018 Cochrane systematic review on the use of flu shots in the elderly found that available data indicate that thirty people would need to be vaccinated in order to prevent one case of influenza, but this evidence “is limited by biases in the design or conduct of the studies.”
Furthermore, “The available evidence relating to complications is of poor quality, insufficient, or old and provides no clear guidance for public health regarding the safety, efficacy, or effectiveness of influenza vaccines for people aged 65 years or older.”
No Good Evidence Flu Shots Reduce Transmission or Complications
In an article summarizing the findings of their three 2018 systematic reviews, Cochrane researchers noted that “There is little evidence on prevention of complications, transmission, or time off work.”
Also, while the CDC claims that tens of thousands of flu deaths occur each year based on mathematical models, the average number of deaths attributed to influenza on death certificates is little more than 1,000 yearly. Therefore, “the actual threat is unknown (but likely to be small) and so is the estimation of the impact of vaccination.”
While Cochrane reviews found insufficient evidence that influenza vaccines prevent transmission, a 2018 study in the journal PNAS found that infected people who had received a flu shot shed over six times as much aerosolized virus in their breath as infected individuals who did not get the vaccine. This is significant because airborne aerosol transmission may be an underrecognized but important mode of transmission for influenza viruses.
Evidence Flu Shots Inhibit Rather than Build Robust Immunity
When McLaren says that the flu shot builds immunity, what it means is that the vaccine stimulates the production of antibodies, which are assumed to equal immunity. As the 2018 Cochrane reviews on flu shots for children and healthy adults both noted, flu shot formulations change each year and are tested using the surrogate outcome of antibody levels despite the fact that literature reviews had consistently shown that “antibody responses are not sufficient predictors of field protection”.
Influenza vaccine manufacturers also acknowledge that a high level of antibodies in the blood does not necessarily equate to immunity. For example, GlaxoSmithKline’s Fluarix insert includes the disclaimer that “Specific levels of hemagglutination-inhibitation (HI) antibody titer post-vaccination with inactivated influenza virus vaccines have not been correlated with protection from influenza illness but the HI antibody titers have been used as a measure of vaccine activity.” Additionally, antibodies produced by vaccination confer “little or no protection against another virus” and “might not protect against a new antigenic variant of the same type or subtype.”
This is significant given that there are around 200 known viruses that cause what are broadly known as “influenza-like illneses” (ILI), and laboratory testing to verify that cases of “the flu” are actually caused by the influenza virus isn’t usually done.
While flu shots contain inactivated viral antigen components that are not capable of infection, side effects of vaccination can resemble symptoms of the flu, such as fever. To people experiencing such side effects, of course, it hardly matters that they don’t actually have “the flu”. What presumably matters, from their perspective, is that they feel like they do.
However, the claim that flu shots cannot give you the flu is particularly misleading for another reason, which is that studies have shown that repeated annual vaccination can increase your risk of influenza illness as well as of non-influenza respiratory viral infections. So, in that sense, you can potentially get the flu by getting an annual flu shot.
As the Cochrane article summarizing its most recent reviews noted, there is an assumption underlying the CDC’s flu shot recommendations (and studies estimating vaccine effectiveness) “that influenza vaccination does not affect the risk of non-influenza” illnesses, but this assumption is contradicted by a randomized, placebo-controlled study finding a significantly increased risk of non-influenza respiratory infections among those who received a flu shot.
A CDC-funded study published in Clinical Infectious Diseases in 2014 found that the more often people had been vaccinated in prior years, the less effective the flu shot was for the current season.
A 2011 study in the Journal of Virology shed light on the possible mechanisms for this increased risk. Its authors found that vaccination skews the immune system toward an antibody response at the opportunity cost of the additional robust cell-mediated immunity that is conferred by infection. Whereas the immunity gained by infection confers protection not only against the infecting strain, but also other strains of influenza, vaccination does not confer this benefit.
The 2012 randomized controlled study in Clinical Infectious Diseases mentioned by the Cochrane authors found no significant difference in the risk of influenza infection between children who received a flu shot and children who received a placebo, while vaccinated children had a significantly increased risk of non-influenza respiratory viral infections.
Among the viruses that vaccine recipients were infected with at a higher rate were rhinovirus, coxsackie virus, and common human coronaviruses. A study published in Vaccine in January 2020 noted that prior studies had indicated that getting a flu shot “may increase the risk of other respiratory viruses” and found that, among Department of Defense personnel during the 2017 – 2018 flu season, vaccination was associated with a significantly increased risk of infection with coronaviruses.
The opportunity costs associated with getting a flu shot every year might help to explain why the vaccine for the 2018 – 2019 flu season was associated with a negative effectiveness among adults aged eighteen to sixty-four years against the influenza A(H3N2) strain that emerged in the latter part of the season. While this study, published in the Journal of Infectious Diseases, was not powered enough in sample size for this finding to attain statistical significance, the authors acknowledged that it indicated a “higher odds of influenza among vaccinated compared with unvaccinated” patients and that, at best, the data overall suggested that “vaccination did not significantly reduce medically attended influenza illness due to A(H3N2) virus infection.”
Finally, the claim that getting a flu shot is “the best way” to prevent “the flu” is not supported by scientific evidence. In addition to the aforementioned problems, there are no studies comparing rates of clinical infection and disease severity between people who choose to get an annual flu shot and people who choose not to get the vaccine but make healthy lifestyle choices that support natural immune function, including eating a healthful diet; ensuring sufficiency of nutrients essential for the proper functioning of the immune system, including vitamin D; mitigating exposure to environmental toxins, including mercury; and exercising regularly.
In sum, contrary to the promotional information presented by McLaren:
- Evidence is lacking that influenza vaccination is effective in children under six years of age, and for children under age two, there is no evidence along with an alarming lack of safety studies.
- Evidence is lacking that influenza vaccination during pregnancy is effective or safe, with a particularly concerning lack of randomized, placebo-controlled trials supporting the CDC’s position that it is safe for women to receive a flu shot even if it contains mercury and even during their first trimester.
- Evidence is lacking that influenza vaccines reduce the risk of complications from influenza infection, including among the elderly.
- Evidence is lacking that flu shots prevent transmission, and one study found that vaccinated individuals shed significantly more aerosolized virus than infected individuals who did not get a flu shot.
- Evidence is lacking that getting a flu shot every year is more effective at preventing severe flu than making healthy lifestyle choices, and studies indicate that repeated annual vaccination may increase the risk of infection with a novel pandemic strain of influenza and may also increase the risk of infection with non-influenza respiratory viral infections.
I searched the McLaren Health Plan website for a media contact to request a comment for this article. The site instructs those seeking “media related information” to contact the company’s Marketing Coordinator via email. I did so on May 5, 2020, briefly summarizing in bullet point how each of the claims presented in their promotional material was misleading and requesting a response for the record. McLaren did not respond to my request for comment.
Of course, when so-called “Health Maintenance Organizations” and other providers make such claims, they are just following the example set by government health officials. Consumers should demand better of companies that claim to be serving the interests of public health as opposed to serving the state and the financial interests of the pharmaceutical corporations.
Such outcomes also highlight the importance of questioning the extent to which or whether the government should be involved in determining how health care providers conduct their business. The argument can easily be made that the interference of government bureaucrats in our affairs is precisely the problem, as illustrated by the CDC’s influence on “standard of care” with respect to flu shots.
 McLaren Health Plan, “Health, Wellness and You”, March 2020.
 Shabir A. Madhi, “Influenza Vaccination of Pregnant Women and Protection of Their Infants”, New England Journal of Medicine, September 4, 2014, https://doi.org/10.1056/NEJMoa1401480. Food and Drug Administration, “Vaccines Licensed for Use in the United States”, accessed May 4, 2020, https://www.fda.gov/vaccines-blood-biologics/vaccines/vaccines-licensed-use-united-states.
 GlaxoSmithKline Biologicals, Fluarix Package Insert, accessed May 4, 2020, https://www.fda.gov/vaccines-blood-biologics/vaccines/fluarix.
 James G. Donahue et al., “Association of spontaneous abortion with receipt of inactivated influenza vaccine containing H1N1pdm09 in 2010-11 and 2011-12”, Vaccine, September 25, 2017, https://doi.org/10.1016/j.vaccine.2017.06.069.
 For discussion and documentation, see: Jeremy R. Hammond, “The CDC’s Criminal Recommendation for a Flu Shot During Pregnancy”, JeremyRHammond.com, May 14, 2019, https://www.jeremyrhammond.com/2019/05/14/the-cdcs-criminal-recommendation-for-a-flu-shot-during-pregnancy/.
 Demicheli et al., “Vaccines for preventing influenza in healthy adults”.
 Michael T Osterholm et al., “Efficacy and effectiveness of influenza vaccines: a systematic review and meta-analysis”, The Lancet Infectious Diseases, October 26, 2011 (published in print January 1, 2012), https://doi.org/10.1016/S1473-3099(11)70295-X.
 Tom Jefferson et al., “Why have three long-running Cochrane Reviews on influenza vaccines been stabilized?” Cochrane Community, January 29, 2018, https://community.cochrane.org/news/why-have-three-long-running-cochrane-reviews-influenza-vaccines-been-stabilised.
 Raymond Tellier, “Review of Aerosol Transmission of Influenza A Virus”, Emerging Infectious Diseases, November 2006, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3372341/.
 Jefferson et al., “Vaccines for preventing influenza in healthy children”. Demicheli et al., “Vaccines for preventing influenza in healthy adults”.
 GSK, Fluarix Package Insert.
 Tom Jefferson et al., “Why have three long-running Cochrane Reviews on influenza vaccines been stabilized?”
 Huong Q. McLean et al, “Impact of Repeated Vaccination on Vaccine Effectiveness Against Influenza A(H3N2) and B During 8 Seasons”, Clinical Infectious Diseases, September 29, 2014, https://doi.org/10.1093/cid/ciu680.
 Danuta M. Skowronski, “Association between the 2008–09 Seasonal Influenza Vaccine and Pandemic H1N1 Illness during Spring–Summer 2009: Four Observational Studies from Canada”, PLoS Medicine, April 6, 2010, https://doi.org/10.1371/journal.pmed.1000258.
 Rogier Bodewes et al, “Annual Vaccination against Influenza Virus Hampers Development of Virus-Specific CD8+ T Cell Immunity in Children”, Journal of Virology, November 2011, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3209321/.
 Benjamin J. Cowling et al., “Increased Risk of Noninfluenza Respiratory Virus Infections Associated With Receipt of Inactivated Influenza Vaccine”, Clinical Infectious Diseases, June 15, 2012, https://doi.org/10.1093/cid/cis307.
 Cowling et al.
 Greg G. Wolff, “Influenza vaccination and respiratory virus interference among Department of Defense personnel during the 2017–2018 influenza season”, Vaccine, October 10, 2019 (published in print January 10, 2010), https://doi.org/10.1016/j.vaccine.2019.10.005.
 Brenden Flannery et al., “Spread of Antigenically Drifted Influenza A(H3N2) Viruses and Vaccine Effectiveness in the United States During the 2018–2019 Season”, Journal of Infectious Diseases, October 30, 2019 (in print January 1, 2020), https://doi.org/10.1093/infdis/jiz543.