Vaccine Letters

Sampling of IDSA Letters Opposing Bills to

Make Vaccines Safer & Address Autism/Mercury Concerns

To see all letters published click HERE.

Sampling of a few IDSA letters below regarding vaccines, the relationship to autism and why they should remain on the market in spite of the potential damage they cause.

Opposing Maryland Bill 586

February 14, 2008

The Honorable Richard B. Weldon

Maryland House of Delegates

House Office Building, Room 324

6 Bladen St.

Annapolis, MD 21401

Dear Representative Weldon,

I am writing on behalf of the Infectious Diseases Society of America (IDSA) to

express the Society’s strong opposition to Maryland House Bill 586, which would

prohibit administering vaccines that contain more than 1.25 micrograms of mercury

per 0.5 milliliter dose. IDSA represents more than 8,000 infectious diseases

physicians and scientists devoted to patient care, education, research, and public

health planning. The Society's members focus on the epidemiology, prevention,

diagnosis, investigation, and treatment of infectious diseases in the U.S. and abroad.

Our members care for patients of all ages with serious infections, including influenza

and other vaccine preventable diseases.

The legislation, while well intentioned, uses flawed and refuted “pseudo-scientific”

evidence of an association between the form of mercury used in vaccines and adverse

effects on children. Furthermore, it has the potential to cause significant harm by

leading to overall reduced vaccination rates as well as unavailability of influenza

vaccines for children. This would be a double blow because influenza can be very

serious for young children and because children are the most significant transmitters

of influenza to the population at large. This legislation’s passage would serve

absolutely no beneficial purpose.

THE FACTS ABOUT THIMEROSAL

Thimerosal, or sodium ethylmercury thiosalicylate, is a preservative that has been in

use since the 1930s for vaccines and other pharmaceutical products. It is no longer

used in most of the vaccines that are commonly given to U.S. children, although some

vaccines against influenza, tetanus, and diphtheria still contain it. Preservatives are

necessary for vaccines that are packaged in multi-dose vials. These vials contain

enough volume for the administration of many doses of vaccine, but the fact that one

must repeatedly puncture the vial’s rubber stopper to withdraw the doses could leave

the fluid vulnerable to contamination, if no preservative is added. Single-dose vials or

pre-filled syringes do not require preservatives, but are more expensive and take up

more storage space. The ethylmercury that is in thimerosal is completely different

from the methylmercury that has been associated with some kinds of neurological

damage (but NOT with autism). Grouping these two compounds together is

misleading and has no scientific basis.

Page Two: Thimerosal Letter

In 1999, vaccine manufacturers in the U.S. and Europe were asked to prepare their vaccines

without thimerosal. This request was the result of a theoretical concern about giving ethylmercury

to infants less than 6 months of age. There was no evidence then—and there is no evidence

now—of an association between thimerosal and autism. The concern that there could be an

association between thimerosal exposure in vaccines and childhood autism is not grounded in

science. Dr. Nancy J. Minshew, a leading autism researcher at the University of Pittsburgh,

recently was quoted by the Pittsburgh Post-Gazette as saying that “the weight of the evidence

[against a correlation between autism and thimerosal] is so great that I don't think there is any

room for dispute. I think the issue is done.”

A few of the more important lines of evidence about thimerosal and autism are summarized in the

paragraphs that follow and several scientific papers that will allow the interested reader to delve

more deeply into the subject are referenced.

The Institute of Medicine (IOM), an expert, independent and non-political division of the National

Academy of Sciences, has reviewed all of the evidence and concluded that there is no association

between thimerosal and autism. They looked at the most important studies that have been cited

in support of an association and found them to be flawed. Furthermore, the findings from those

studies could not be reproduced by others, which is a fundamental hurdle that any new scientific

hypothesis must cross in order to be accepted (Institute of Medicine, 2004).

Perhaps the best evidence against the argument that thimerosal causes autism is that removal of

thimerosal from vaccines in both the U.S. and other countries has not led to a decrease in the

number of new cases of autism. If autism were due to excess infant exposure to thimerosal, then

removal of thimerosal should have lead to a decrease in autism. In Denmark, for the 19 years

when thimerosal was used in infant vaccines in that country, there was no increase in autism rates.

The rates actually began to rise in 1992, when thimerosal was removed from vaccines in Denmark

(Madsen, 2003). An even more compelling study was published from Montreal, Canada in 2006.

In that study 27,749 schoolchildren immunized between the years 1987 and 1998 were followed

through 2005. Thimerosal was completely removed from all vaccines beginning in 1996. From

that time forward, the incidence of autism actually increased compared to previous years

(Fombonne, 2006).

As such, it is senseless to enact legislation that removes thimerosal from vaccines, thinking that

we will be protecting our children. In reality, if this legislation is passed, we run a grave risk of

harming these same children due to unintended consequences.

THE CONSEQUENCES OF MANDATING THIMEROSAL-FREE VACCINES

IDSA has significant concerns that passage of this legislation would perpetuate the misleading

notion that vaccines are not safe or that vaccine safety oversight is inadequate. The legislation

could lead people to mistakenly conclude that vaccines still containing thimerosal, such as certain

influenza vaccines, are not safe. Likewise, it could cause some parents to question vaccines’

safety regardless of whether they contain thimerosal. Overall immunization rates could fall and

the rates of many vaccine preventable diseases could rise. This includes measles, whooping

cough, and meningitis to name just a few, in addition to influenza.

Page Three: Thimerosal Letter

Furthermore, the legislation could result in children going unvaccinated from influenza because

current U.S. manufacturing capacity cannot produce enough thimerosal-free vaccine each year to

vaccinate all children. Additionally, there is no guarantee that the supply situation will improve

by the legislation’s proposed implementation date of January 1, 2009 as thimerosal free vaccines

are more costly and more difficult to package. Influenza vaccine without thimerosal needs to

come in either pre-filled syringes or single dose vials, both of which are more expensive. The

increase in cost is estimated to be between 16-24%. This means that for every 100,000 persons

enrolled in the state’s Medicaid program who are vaccinated for influenza, the state will pay an

additional $160,000 to $240,000. Using scarce resources to buy thimerosal-free vaccines would

limit the state’s ability to purchase other critical vaccines and life-saving drug therapies.

Finally, mandating thimerosal free vaccines would add even more complexity to the current

vaccine delivery system. The number of vaccines given to infants and children has increased from

7 in 1985 to 10 in 1995 and to 14 for 2007. With new vaccines being introduced, changes in

scheduling, and all of the other complexities of vaccination delivery, it is already difficult for

providers to stay current with the recommendations. Adding a requirement that providers may use

only vaccines that are thimerosal free would add even more complexity to the delivery system.

CONCLUSION

In sum, this legislation would do harm as a ban on thimerosal in vaccines likely would cause

significant, negative consequences to the overall health of your communities. Vaccines are among

the greatest achievements in the history of science, and represent the single greatest hope for

several as yet unconquered diseases like AIDS, malaria and avian influenza. Not only is the

legislation unnecessary but it is also potentially harmful because it would perpetuate false and

misleading information about vaccine safety and would limit critical vaccine supply.

For these reasons, I urge you not to support Maryland House Bill 586. If you have any

questions concerning this matter, please contact Robert J. Guidos, JD, IDSA’s Director of Public

Policy and Government Relations, at 703-299-0200. You also may want to visit the National

Network for Immunization Information at http://www.immunizationinfo.org/ for more information

about thimerosal and other vaccine issues.

Sincerely,

Donald Poretz, MD, FIDSA

IDSA President

cc:

Stephen H. Johnson

General Counsel, Director of Law & Advocacy Division

Maryland State Medical Society

References

1. Andrews et al. Retrospective cohort study of 109,000 children born in the UK from 1988-

1997. Pediatrics, September 2004

2. Clarkson TW, Magos L, Myers GJ. The toxicology of mercury- current exposures and clinical

manifestations. New England Journal of Medicine 2003;349(18):1731-7

3. Clements CJ. The evidence for the safety of thimerosal in newborn and infant vaccines.

Vaccine 2004;22(15-16):1854-61

4. Fombonne E, Zakarian R, Bennett A, Meng L, McLean-Heywood D. Pervasive developmental

disorders in Montreal, Quebec, Canada: prevalence and links with immunizations. Pediatrics

2006;118(1):e139-50

5. Heron et al. Prospective cohort study of over 14,000 children born in Avon (UK) in 1991-

1992. Pediatrics, September 2004

6. Hviid et al. Retrospective cohort study of all 467,450 children born in Denmark between 1990

and 1996. JAMA, September 2003

7. Institute of Medicine. Immunization Safety Review: vaccines and autism. Washington, DC.

National Academy Press, 2004

8. Madsen KM, Lauritsen MB, Pedersen CB. Thimerosal and the occurrence of autism: negative

ecological evidence from Danish population based data. Pediatrics 2003;112(3):604-6

9. Parker SK, Schwartz B, Todd J, Pickering LK. Thimerosal containing vaccines and autistic

spectrum disorder: a critical review of published original data. Pediatrics 2004;114(3):793-804

10. Thompson et al. Retrospective cohort study of 1,047 U.S. children who received vaccines

during the 1990s to evaluate 42 neuropsychological outcomes (excluding autism). New

England Journal of Medicine, September, 2007

11. Schechter et al. Ecological study of time trends in autism diagnoses among clients of the

California Department of Developmental Services from 1995-2007, a period encompassing the

1999-2001 removal of thimerosal from most US vaccines. Arch Gen Psychiatry, January 2008

12. Virginia Hughes. “Mercury Rising.” Nature Medicine: Vol. 13, No. 8, August 2007

See letter at IDSA website:

http://www.idsociety.org/Content.aspx?id=10016

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February 14, 2008

The Honorable James C. Rosapepe

Maryland Senate

James Senate Office Building, Room 314

11 Bladen St.

Annapolis, MD 21401

Dear Senator Rosapepe,

I am writing on behalf of the Infectious Diseases Society of America (IDSA) to

express the Society’s strong opposition to Maryland Senate Bill 304, which would