by Dr. Christine Gonzalez (Integrative PharmD, CHC)
Now that flu season is upon us, many are still deciding whether to get their yearly flu shot. With so much controversy in the press regarding the link between mercury in vaccines and neurotoxicty (autism and Alzheimer’s disease), no wonder people are concerned and confused. While the benefit of flu vaccination for groups at high-risk for serious flu complications is well established, the actual benefit versus potential risk for the average healthy adult is highly debated. Some of the main issues on the table surround the effectiveness of the flu vaccine and the safety of additives used in some of the formulations. Not surprisingly, the importance of proper self-care and immune support as a means to stay flu-free is often overlooked.
The flu vaccine is essentially a new product each year and is reformulated to contain the three most likely strains of flu based on epidemiological studies. At least one of the strains is changed each year based on this information. It is basically the experts' best guess but there is always the chance of variability within a flu season. The effectiveness percentages cited for flu vaccination are only valid when the vaccine closely matches the circulating strain. Therefore, the flu vaccine does not guarantee 100% protection from the flu! Its effectiveness is based on the spectrum of flu strains covered by the vaccine and the individual’s immune response to the vaccine. The various studies trying to establish the cost effectiveness and benefit of flu vaccination for healthy workers have produced conflicting results. Therefore, the average healthy adult can consider the flu shot as an option and not a requirement for staying flu-free during flu season.
The most commonly administered flu shot is called Fluzone. It is approved for use in people 6 months and older, including healthy people and people with chronic medical conditions. It is prepared from the fluids of chick embryos injected with a special type of dead or inactivated flu virus. Each adult dose contains 25 micrograms of thimerosal. Thimerosal is a mercury derivative added as a preservative to prevent contamination and bacterial growth in multi-dose vials. There are thimerosal-free, single-dose products that have been available since December of 2004. But these are usually in limited supply and reserved for infants, children, and pregnant women.
Thimerosal is metabolized to ethylmercury. This is different from methylmercury, the form found in seafood. Methylmercury is a neurotoxin and has been the focus of many studies. The current mercury guidelines are based on the methylmercury studies. Due to a lack of solid data on the comparative toxicities of ethyl-versus methylmercury, the FDA views both with the same risk potential. According to the CDC, "there is no convincing scientific evidence of harm caused by the low doses of thimerosal in vaccines, except for minor reactions like redness and swelling at the injection site." But in July 1999, the Public Health Service agencies, the American Academy of Pediatrics, and vaccine manufacturers agreed on the precautionary reduction or elimination of thimerosal from vaccines. The theoretical potential for neurotoxicity has been enough of a concern for the FDA to support vaccine manufacturers to reduce or eliminate thimerosal from vaccines. This should clearly serve as a warning sign!
While Fluzone is latex-free, it does contain gelatin, formaldehyde, and polyethylene glycol ether-the latter two in "residual amounts". Gelatin is derived from the skins, connective tissues, or bones of cows or pigs. It is responsible for many of the allergic reactions associated with this vaccine. Formaldehyde is classified as a "probable human carcinogen" by the U.S. Environmental Protection Agency and as a "known human carcinogen" by the International Agency for Research on Cancer. Polyethylene is related to antifreeze and is resistant to breakdown in the body. It is toxic to cells and can interfere with proper immune system functioning.
The nasal-spray flu vaccine, FluMist (sometimes called LAIV for "live attenuated influenza vaccine"), is approved for use in healthy people aged 2 to 49 years, who are not pregnant. It is made with live, weakened flu viruses that do not cause the flu. This vaccine does not contain thimerosal but does contain monosodium glutamate (MSG), porcine gelatin, and the antibiotic gentamicin. Although MSG is "generally regarded as safe" by the FDA, there is a significant amount of data on adverse reactions and safety that is being reexamined. It is also being studied for mutagenic, teratogenic and reproductive effects. Porcine gelatin is produced from the skin, connective tissue, or bone of pigs. As previously mentioned, it is responsible for many of the allergic reactions associated with this vaccine. Gentamicin is an antibiotic that can also cause allergic reactions.
According to a call-center representative at Sanofi Pasteur, the manufacturer of Fluzone, they do not have information on studies correlating adverse effects with specific vaccine ingredients. They do not cite data on the potential toxicity of the previously mentioned additive ingredients. All adverse effects observed in their clinical trials are attributed to the vaccine as a whole. In addition and as found on the package insert, "Fluzone vaccine has not been evaluated for carcinogenic or mutagenic potential, or for impairment of fertility." Similarly, "FluMist has not been evaluated for its carcinogenic or mutagenic potential or its potential to impair fertility." But just because there is no data, does not mean the potential for toxicity does not exist. While the toxicity of these additive ingredients at the levels found in various flu vaccines continues to be a source of debate, these are certainly not innocuous substances.
According to the CDC, those who want to reduce their chances of getting the flu can get vaccinated. But it is recommended for those at high risk of having serious complications or those who live with or care for those at high risk for serious complications. The reality is that the flu virus can cause serious illness, even death, for certain people with chronic health conditions. Every year, more than 200,000 people are hospitalized and 36,000 die as a result of the flu and its complications. There is an increased risk for young children 6 months to 4 years and the elderly. It is important to evaluate the full risk to benefit of getting the flu shot versus not, especially for high-risk groups. But considering all the questions surrounding the effectiveness and safety of yearly flu vaccination, this is not a decision to be taken lightly. If you opt against flu vaccination, it is important to be aware of non-pharmacological immune support during flu season. Some basic tips for avoiding and dealing with the flu include:
– Wash your hands frequently
– Minimize contact with people who have the flu
– Do not share cups, glasses, or utensils
– Disinfect workspace (desk, keyboard, and telephone)
– Stay hydrated
– Eat a diet rich in whole grains and the rainbow of fruits and vegetables. Some immune supportive foods include citrus fruits, dark and leafy greens, parsley, cauliflower, tomatoes, and carrots. Also consider increasing your intake of probiotic-rich foods like yogurt, kefir, kombucha, miso, and sauerkraut (raw and fermented).
– Get plenty of rest
– Some supplements to consider include a daily multivitamin and antioxidants, echinacea, goldenseal, immune-enhancing mushrooms (maitake, shiitake, and reishi), and astragalus
