When I recommended here a month ago that we all get vaccinated against influenza this year, I had no idea how much controversy it would stir up. Some of the concerns are legitimate, but we have alternatives. Other concerns stem from irresponsible rants on the Internet that I've traced back to a totally discredited South Carolina doctor.
My article here last month jumped the gun. I knew that the flu authorities at the U.S. Centers for Disease Control and Prevention (CDC) wanted to talk with me so that I could help get the word out. But since CDC and the Health Central Network weren't able to work out the arrangement in time, I wrote then because the flu season was already upon us.
Now, I have had the opportunity to interview the CDC's expert on the flu. Carolyn B. Bridges, MD, is the associate director for science in its influenza division. I focused that interview on the concerns that you shared in your comments to last month's article.
One short comment succinctly summarizes those concerns. "I don't get the flu shot because it has [thimerosal] and other toxic substances,"mb wrote. "And the flu virus mutation which is going around is just as likely not to be covered by the virus design[ed] for the year. Also, I don't want a live virus vaccination for anything, as it would automatically give me the disease in question."
The biggest concern is the use of thimerosal, a preservative that the United States Code of Federal Regulations requires in multi-dose vials of flu vaccines. Flaming those concerns the most has been a doctor in South Carolina.foundDr. Fudenberg "guilty of engaging in dishonorable, unethical, or unprofessional conduct," fined him $10,000, ordered him to surrender his license to prescribe controlled substances (narcotic drugs), and placed his license on indefinite suspension."
And what about Dr. Fudenberg's "facts" about mercury and aluminum in the flu vaccine?
Indeed, some flu shots contain thimerosal, which is about 50 percent mercury by weight. But it's not the bad mercury we worry about in fish."Methylmercury makes its way through the food chain in fish, animals and humans. At high levels, it can be toxic to people," according to the Children's Hospital of Philadelphia. "Thimerosal -- a preservative still used in the influenza vaccine --contains a different form of mercury called ethylmercury. Studies comparing ethylmercury and methylmercury suggest that they are processed differently in the human body. Ethylmercury is broken down and excreted much more rapidly than methylmercury. Therefore, ethylmercury (the type of mercury in the influenza vaccine) is much less likely than methylmercury (the type of mercury in the environment) to accumulate in the body and cause harm.
Note that the Children's Hospital says that thimerosal is "still used" in the influenza vaccine. The governments of developed countries have removed it from vaccines given to children, who are of course most at risk of mercury poisoning."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," according to the CDC. "However, in July 1999, the Public Health Service agencies, the American Academy of Pediatrics, and vaccine manufacturers agreed that thimerosal should be reduced or eliminated in vaccines as a precautionary measure."
We can get thimerosal-free vaccines. Perhaps in an excess of caution, I'll do that next year (too late for this year, since I already got my flu shot).
It might not be easy to find. A correspondent named Bob wrote me personally:
"Of the seven sites that I have contacted about the thimerosal free flu shots, five basically laughed at me and told me not to worry. The VA said that I would have to order it for next year and were otherwise noncommittal. The last -Walgreens said that they were aware of it, but would not stock it for only one person. Even my own doctor said the call for it was so small they could not stock it for the flu season and he didn't recall anyone asking for it before. Even emails to news agencies and local newspapers have gotten me no response. Most said it is a non-story."
It's definitely not a "non-story." It is a big story. So I researched it as well as I could this year.
"For someone who is at high risk for influenza complications," Dr. Bridges says, "the potential risk of exposure to thimerosal needs to be weighed against the real risk of complications and death from influenza." But, she added, "There is quite a bit of vaccine out there that is in single dose vials that is mercury free or has only perhaps trace levels of thimerosal. If you have concerns, ask for a thimerosal-free or preservative-free vaccine. Clinicians may not choose to order it, so you may have to check other places to find it.
The starting place turns out to be Johns Hopkins Bloomberg School of Public Health. It describes the five inactivate flu vaccines and the one live flu vaccine available in 2008/2009.
Two of these vaccines, CSL Limited's Afluria and sanofi pasteur's Fluzone, are thimerosal-free, that is mercury-free, in their single-dose prefilled syringes and prefilled syringes or single-dose vials respectively. GlaxoSmithKline's Fluarix has a trace amount of thimerosal. Fluzone, however, does have a trace amount of another toxic substance, formaldehyde.
None of the flu vaccine have the other toxic substance that Dr. Fudenberg wrote about, aluminium or alum any more, if they ever did, according to the Johns Hopkins table. Dr. Bridges confirms this:"As for aluminum, none of the U.S. flu vaccines contains aluminum that I am aware," she wrote me. "However, an adjuvant (a substance added to a vaccine to help boost the immune response and, hence, level of protection against getting sick) that has been evaluated in some vaccines does contain aluminum -- theadjuvant is called alum. I do not believe any influenza vaccine is licensed for use anywhere, though, that uses alum."
Next year I'll search for Afluria, since it is the only flu vaccine that is totally free -- not even any trace amounts -- of all these toxic substances. If that fails, I will usesanofi pasteur's Fluzone vaccine. But not even people at CSL Limited or sanofi pasteur could tell me which clinics have their thimerosal-free vaccine. That's because all these companies use a middle man, a so-called distributor.
However, Donna Cary, sanofi pasteur's director of public relations, was able to tell me which distributors have which vaccines on hand or on order at the moment. That information is online in an Excel spreadsheet.
What about the live vaccine, MedImmune's FluMist? The comment by mb, which I cited earlier, says that he or she doesn't want it.
Quite correct. Dr. Bridges confirms that people with diabetes should not take the live vaccine.
And what about mb's other comment that because the virus mutates, it is "just as likely not to be covered" by this year's vaccine.
That is half true. The virus does mutate from year to year."So far things look very good," Dr. Bridges told me. "We are very encouraged how it is going to work. Most of the time the decision is correct and the predominant strain is well covered by the vaccine. In the past 21 years we have had only one year when the vaccine was so off -- the strain was so much different from the vaccine -- that there was very little to no benefit. That was the 1997-98 season when the Sydney strain emerged. We have had some other years when there wasn't a perfect match, but the viruses have been similar enough that the vaccine provided at least partial protection. Even when we didn't have an optimal match, lots of studies still showed benefit."
Even before Dr. Bridges and I talked, she read my previous article. She took exception to a couple of points that I made.
"If you live in Alabama, Delaware, Georgia, Kentucky, Mississippi, South Carolina, Virginia, or West Virginia," I wrote, "it may be too late for you [to get vaccinated]. The flu has already reached a 'moderate' level in those eight states, according to a great new Google tool."
I met that it might be too late -- if you already have the flu, but didn't write that well. Dr. Bridges says that, "CDC would like to emphasize that yearly flu vaccination should continue throughout the influenza season, into December, January, and beyond. Most of the time influenza activity peaks in January or later, so people who reside in the states listed above should still go out and get a flu vaccine if they haven't already."
She also emphasize that there are important limitations to Google Flu Trends tool:
"Flu Trends is a useful adjunct to the current CDC surveillance systems, but it should not be considered a replacement. One of the main strengths of this system is its timeliness. This system can act as an early warning system for outbreaks since the lag time on this system is only one day, compared with other systems that are updated weekly. Another advantage is its simplicity. The system was very complex to develop, but now is fully automated. Also, the system doesn’t rely on reporting by providers, which can be patchy and time-consuming.
However, evaluation of the data quality is difficult with a system like this. There is no laboratory confirmation of cases. Any blip in the data needs verification that an outbreak is indeed occurring. The overall quality of the data depends on the assumption that web searches do in fact reflect health care-seeking behavior. It is possible that newspaper headlines can cause a spike inILI -related web searches that have nothing to do with someone actually being sick. A drug recall for a brand of cough syrup could also cause a false spike. And finally, it’s unclear how people will change their web searching behavior once it is known that Google is using their data for surveillance. The stability of the system is dependent on consistent Internet access over time. And finally, it will need ongoing adjustment and validation to keep it up-to-date."
Further, she says that the Google Flu Trends tool has some additional limitations:
Accuracy, although this system correlated well, we can not know the effects of media or other biases until they happen.
The tool may miss cases of influenza spreading among elderly people, because they are less likely to use the Internet than younger people
Also, many people who search for flu-related terms have viral infections that are not actually influenza.
Not every person who searches for "flu" is actually sick, but a pattern emerges when all the flu-related search queries from each state and region are added together.All in all, your comments and the response by Dr. Bridges shed a lot of light on a complicated flu shot picture. While the picture is complicated, it's not cloudy:
We need to get our annual flu shot. If we can, I think it would be wise to get one without any toxic additives. But if that's not possible, even a shot that contains thimerosal is better than the possible alternative -- a case of flu.
Published On: December 14, 2008