Young children spread the flu (and lots of other stuff) so will likely be a major vector in the spread of swine flu (H1N1). But according to the Centers for Disease Control, fewer than 45 percent of babies, toddlers, and preschoolers are usually vaccinated against influenza. “But, why?” you ask. Why is this post in the Environment & Wildlife causes blog at Care2? Because one of the concerns is mercury. Because environmentally conscious parents work to keep toxins out of their children’s water, food, and home and many are uncomfortable injecting even small amounts of this toxic heavy metal into their children’s bloodstreams.
Mercury in the Environment
When the heavy metal mercury is released into the environment – mostly from digging up and burning coal, but there are few other sources as well – it contaminates rivers, streams, and ocean waters where it is converted into an organic form of the metal – methyl mercury. Methyl mercury then accumulates in fish and wildlife and eventually people.
Mercury is a poison that targets the nervous system. This is of special concern for children (and therefore pregnant women) because mercury can permanently damage a developing brain. To prevent mercury building up to toxic levels in the body, EPA recommends keeping exposure under 0.1 mcg per kilogram of body weight. For most people, this means being careful not to eat too much fish too high in mercury (which is very upsetting for the tuna industry but good for recovering the swordfish population).
Mercury in the Flu Vaccine
In the late 1990s and early 2000s, concerns that ethyl mercury in the many vaccines commonly administered before the age of two would bring infants above the EPA threshold encouraged the vaccine industry to eliminate the mercury-containing preservative thimerosal from all vaccines given to children younger than six years old. Mercury-preservatives are still used in vaccines given to adults, including all multi-dose vial preparations of the flu vaccine.
There are four manufacturers of the H1N1 vaccines that will be available in the United States – three for injected vaccines and one for a nasal mist vaccine. The injectable vaccines are available either in single dose vials or pre-filled syringes, which are mercury-free, or a 10 dose vial, which contains about 25 mcg of mercury per full dose. The nasal mist is mercury-free.
However of the mercury-free options, only the Sanofi Pasteur single-dose and 1/2-dose preparations is approved for infants and toddlers. The Novartis single-dose preparation is approved for kids four years and older. The CSL single-dose preparation is only approved for adults. So, parents of babies and toddlers looking for mercury-free vaccines will only have the one choice.
To Worry or Not to Worry about Mercury in the Flu Vaccine
The World Health Organization has concluded that use of thimerosal is acceptable in vaccines. The organization feels that risk is unproven and the benefit of using the preservative, which allows manufacture of multi-dose vials essential in the developing world, outweighs a theoretical risk of mercury in the vaccine. But for those of us with the luxury of obtaining a mercury-free, single-dose vaccine, should we?
The ethyl mercury used in vaccines is different from the methyl mercury found in fish in that it is excreted from the body much faster, usually in less than a week, so it doesn’t build up to toxic levels as easily. Unfortunately, the National Institutes of Health fact sheet on the safety of thimerosal was disappointingly unspecific on why thimerosal is safe.
Note that to protect against both the seasonal flu and H1N1, you need two vaccines.
Dr. Robert Sears, author of The Vaccine Book, recommends that pregnant women and children under three skip the flu vaccine unless they can get the single-dose, mercury-free injection or the nasal mist (not for preganant women).
Practicality of the Flu Vaccine for Children
Anyone under 10 getting vaccinated for the first time is supposed to get two doses spaced a month apart (If your child missed a dose the first time they were vaccinated, they need two doses this time). If you are vaccinating for both seasonal flu and H1N1, is that four doses over four months? That’s Dr. Sears’s recommendation anyway.
A query on my moms list serv elicited a response from a Department of Health and Human Services staff person (I live on Capitol Hill; it’s a connected group of moms.) who assured me that both the seasonal flu and H1N1 could be administered together, provided I can find the two from the same provider.
Update from that listserv post: Since posting to my neighborhood parents’ e-mail list, a few moms have posted stories of their own experiences with the swine flu. It has already hit our neighborhood and those neighbors who’ve had it are reporting that it made their families sicker than anything in recent memory – parents and kids. Not fun and not something to take lightly. Don’t miss Jessica’s personal account here on Care2.
So bottom line?
I don’t know what I’m doing, yet. According to the New York Times, I’m not alone: only 40 to 51 percent of patients surveyed by the Harvard School of Public Health are definitely planning to get the vaccine.
What about you?
Read more about H1N1 innoculations: