It is Time to Eliminate Thimerosal from Influenza Vaccines to Protect Public Health

Why would anyone want to increase their risk of respiratory infections? For maximum impact, please share with your elected representatives at the Federal and State levels.

Take-home up front:

• Multiple studies show that prior influenza vaccination may alter immune responses and increase susceptibility to severe outcomes from other respiratory infections.

• The assumption that influenza vaccination improves overall immune resilience is shown to the false, and we should all call for a reevaluation of the wisdom of injecting mercury into pregnant women, children, or anyone, for that matter.

• If we are serious about making America healthy again, the time to notify your legislators that you expect action is now.

For decades, public health agencies have assured Americans that thimerosal, a mercury-based preservative used in multi-dose influenza vaccines, is safe. The Centers for Disease Control and Prevention (CDC) and the Food and Drug Administration (FDA) have repeatedly stated that ethylmercury, the form of mercury in thimerosal, is quickly excreted and poses no long-term health risk. However, important scientific evidence contradicts these claims, demonstrating that ethylmercury is converted into inorganic mercury in the brain, leading to higher brain burden than methylmercury, accumulating and remaining, as science shows, indefinitely (Burbacher et al., 2005).

Simultaneously, a growing body of peer-reviewed studies suggests that inactivated influenza vaccines—many of which contain thimerosal—are associated with increased rates of non-influenza infections, higher healthcare utilization, and even increased mortality in certain populations (Cowling et al., 2012; Caini et al., 2021; Giner-Soriano et al., 2022). These findings demand immediate policy action: it is time to eliminate thimerosal from all vaccines, starting with influenza vaccines.

Public health agencies justify the continued use of thimerosal by arguing that it prevents bacterial and fungal contamination in multi-dose vials. However, thimerosal remains in vaccines not because it is necessary, but because it is convenient and profitable. Multi-dose vials are cheaper to produce, store, and distribute, reducing costs for vaccine manufacturers and public health agencies at the potential expense of human health. If the priority is truly public health over corporate convenience, legislators must demand the immediate removal of thimerosal from all vaccines and enforce full transparency in vaccine labeling.

The Science Is Clear: Influenza Vaccination and Increased Risk of Other Infections

Influenza vaccines are designed to protect against influenza viruses. Still, a disturbing pattern has emerged in peer-reviewed studies: recipients of inactivated influenza vaccines are at higher risk for non-influenza respiratory infections. Multiple studies now provide ample warning of the immune compromise from thimerosal in flu vaccines.

A randomized controlled trial by Cowling et al. (2012) found that children who received the inactivated influenza vaccine were 4.4 times more likely to contract non-influenza respiratory infections compared to unvaccinated children. The authors hypothesized that influenza vaccination may disrupt temporary nonspecific immunity, a natural defense mechanism that helps protect against multiple pathogens.

Further supporting this concern, a 10-year observational study conducted by Caini et al. (2021) in the Netherlands found that individuals who received the influenza vaccine were 24–33% more likely to seek medical care for influenza-like illness (ILI), acute respiratory infections (ARI), and pneumonia compared to their unvaccinated counterparts. The persistence of this trend across multiple flu seasons suggests a systemic effect rather than a statistical anomaly.

The risks extend beyond seasonal respiratory illnesses. A population-based cohort study by Giner-Soriano et al. (2022) in Catalonia found that individuals who had received an influenza vaccine had a higher risk of pneumonia, hospitalization, and mortality following COVID-19 infection compared to those who had never received an influenza vaccine. These findings raise the urgent question: could influenza vaccination be altering immune responses in ways that make individuals more vulnerable to severe disease from emerging pathogens like SARS-CoV-2?

Rose et al. (2021) found paradoxical increased rates of ILI and pneumonia mortality among influenza vaccine recipients. An increase in influenza-like illnesses (ILI) and acute respiratory infections (ARI) was noted in both 2015 and 2016.​ An increased 90-day mortality rate after hospital-treated pneumonia was observed among vaccine recipients in 2015.

The increased risk of non-influenza infections following vaccination reported by some studies is particularly concerning in high-risk populations. Dierig et al. (2014) found that children vaccinated against influenza were 1.6 times more likely to experience non-influenza influenza-like illness (ILI) compared to their unvaccinated peers. Similarly, Hansen et al. (2021) found that pregnant women who received inactivated influenza vaccines had a twofold higher risk of developing non-influenza infections, while their infants had a 36% increased risk of adverse health outcomes.

Studies support the mechanism of negative effects of thimerosal on immune system functioning as well. A comprehensive review by Jones & Ponomarenko (2022) examined concluded that seasonal influenza vaccines might disrupt immune balance, increasing susceptibility to non-influenza infections by altering cytokine responses and suppressing broader immune defenses.

These studies strongly suggest that influenza vaccination fails to reduce overall respiratory illness and may increase vulnerability to non-influenza pathogens.

Thimerosal: An Immunotoxic and Neurotoxic Preservative with No Justifiable Benefit

The debate over thimerosal’s safety is not new, but recent research has cast even greater doubt on its continued use. Thimerosal is nearly 50% mercury by weight, and mercury is a well-established neurotoxin with documented harmful effects on the brain and nervous system.

Regulatory agencies claim that ethylmercury is safer than methylmercury because it clears from the bloodstream more quickly. However, this assertion ignores a crucial fact:

Burbacher et al. (2005) demonstrated that ethylmercury from thimerosal-containing vaccines is rapidly converted into inorganic mercury, accumulating in the brain and remaining indefinitely. Unlike dietary mercury, which is excreted through the digestive system, injected mercury bypasses natural detoxification pathways and accumulates in organs, particularly the brain. (See IPAK-EDU Information Sheets).

Some regulators have claimed that thimerosal is safe because it is rapidly excreted. This assertion is based on papers by Pichichero et al. (2002, 2009), which measured only short-term blood and urine levels, ignoring long-term retention in the brain found previously.

If mercury from thimerosal remains in the brain for years, it does not matter how quickly it clears from the blood. The damage is already done.

Legislators Must Act: The Policy Solutions We Need Today

The continued use of thimerosal in vaccines is a public health failure that demands immediate corrective action.

We call for the following policy changes:

• An Immediate Ban on Thimerosal in All Vaccines. Mercury does not belong in any vaccine, and its continued use is unjustifiable.

• Mandatory Transparency in Vaccine Labeling. Patients should be explicitly informed if a vaccine contains mercury.

• A Transition to Thimerosal-Free Single-Dose Vials. There is no justification for keeping multi-dose vials when mercury-free alternatives exist.

• A Reevaluation of Influenza Vaccination Policies for Pregnant Women and the Elderly. The risk-benefit profile must be reassessed in light of new evidence.

This is not a debate about vaccines. This is a debate about vaccine safety.

The science is clear. The risks are real. It is time to eliminate thimerosal from all vaccines—before more lives are needlessly affected.

References

• Burbacher TM, Shen DD, Liberato N, et al. (2005). Comparison of blood and brain mercury levels in infant monkeys exposed to methylmercury or vaccines containing thimerosal. Environmental Health Perspectives, 113(8), 1015–1021. DOI: 10.1289/ehp.7712 PUBMED: https://pubmed.ncbi.nlm.nih.gov/16079072/

• Cowling BJ, Fang VJ, Nishiura H, et al. (2012). Increased risk of noninfluenza respiratory virus infections associated with receipt of inactivated influenza vaccine. Clinical Infectious Diseases, 54(12), 1778–1783. DOI: 10.1093/cid/cis307 PUBMED: https://pubmed.ncbi.nlm.nih.gov/22423139/

• Caini S, Paget J, Spreeuwenberg P, et al. (2021). Impact of influenza vaccination in the Netherlands, 2007–2016: Vaccinees consult their general practitioner for clinically diagnosed influenza, acute respiratory infections, and pneumonia more often than non-vaccinees. PLoS One, 16(5), e0249883. DOI: 10.1371/journal.pone.0249883

• Giner-Soriano M, de Dios V, Ouchi D, et al. (2022). Outcomes of COVID-19 infection in people previously vaccinated against influenza: Population-based cohort study using primary health care electronic records. JMIR Public Health Surveillance, 8(11), e36712. DOI: 10.2196/36712 PUBMED: https://pubmed.ncbi.nlm.nih.gov/36265160/

• Jones RP, Ponomarenko A. (2022). Roles for pathogen interference in influenza vaccination, with implications to vaccine effectiveness (VE) and attribution of influenza deaths. Infectious Disease Reports, 14(5), 710–758. DOI: 10.3390/idr14050076 PUBMED https://pubmed.ncbi.nlm.nih.gov/36286197/

• Dierig A, Heron LG, Lambert SB, et al. (2014). Epidemiology of respiratory viral infections in children enrolled in a study of influenza vaccine effectiveness. Influenza and Other Respiratory Viruses, 8(3), 293–301. DOI: 10.1111/irv.12229 PUBMED https://pubmed.ncbi.nlm.nih.gov/24483149/

• Hansen KP, Benn CS, Aamand T, et al. (2021). Does influenza vaccination during pregnancy have effects on non-influenza infectious morbidity? A systematic review and meta-analysis of randomized controlled trials. Vaccines (Basel), 9(12), 1452. DOI: 10.3390/vaccines9121452 PUBMED https://pubmed.ncbi.nlm.nih.gov/34960198/

• Rose N, Storch J, Mikolajetz A, et al. (2021). Preventive effects of influenza and pneumococcal vaccination in the elderly – results from a population-based retrospective cohort study. Human Vaccines & Immunotherapeutics, 17(6), 1844–1852. DOI: 10.1080/21645515.2021.1917242.

• Pichichero ME, Cernichiari E, Lopreiato J, Treanor J. (2002). Mercury concentrations and metabolism in infants receiving vaccines containing thiomersal: A descriptive study. The Lancet, 360(9347), 1737–1741. DOI: 10.1016/S0140-6736(02)11682-5.

• Pichichero ME, Gentile A, Giglio N, et al. (2009). Mercury levels in newborns and infants after receipt of thimerosal-containing vaccines. Pediatrics, 121(2), e208-e214. DOI: 10.1542/peds.2006-3363.

Study in Highlight (Giner-Soriano et al., 2022)

The study titled "Outcomes of COVID-19 Infection in People Previously Vaccinated Against Influenza: Population-Based Cohort Study Using Primary Health Care Electronic Records" (Giner-Soriano et al., 2022) found that individuals vaccinated against influenza had a higher risk of pneumonia, hospitalization, and mortality following COVID-19 infection compared to unvaccinated individuals.

Key Findings:

• Study Population: 309,039 individuals diagnosed with COVID-19 during the first wave (March–June 2020) in Catalonia, Spain.

• Influenza Vaccination Status:

  • 114,181 individuals (36.9%) had been vaccinated against influenza at least once before COVID-19 infection.

  • 194,858 individuals (63.1%) had never been vaccinated.

• Negative Health Outcomes:

  • 19% of vaccinated individuals experienced at least one severe outcome (pneumonia, hospitalization, or death) compared to 5.7% of unvaccinated individuals.

  • Odds Ratios (OR) for Severe Outcomes in Vaccinated Individuals:

    • Hospitalization: OR = 1.14 (95% CI: 1.10–1.19)

    • Pneumonia: OR = 1.12 (95% CI: 1.02–1.23)

    • Death: OR = 1.32 (95% CI: 1.23–1.42)

  • Individuals who were vaccinated recently (2019–2020 flu season) had even higher risks:

    • Hospitalization: OR = 1.16 (95% CI: 1.10–1.23)

    • Pneumonia: OR = 1.12 (95% CI: 1.02–1.23)

    • Death: OR = 1.14 (95% CI: 1.04–1.24)

Conclusions:

• The influenza vaccine did not provide a protective effect against severe COVID-19 outcomes.

• Instead, influenza-vaccinated individuals had an increased risk of hospitalization, pneumonia, and death from COVID-19 compared to unvaccinated individuals.

• The association persisted even after excluding long-term care facility residents, ruling out institutionalized individuals as a confounder.