Flu shots can save kids from coughing, feverish misery and potentially deadly complications such as pneumonia. So Elena Geil was willing to devote "a very intense few weeks" of her time last October to finding her two children and her unborn baby flu shots free of the mercury-containing preservative thimerosal.
Although most scientific studies say otherwise, some doctors, researchers and parents including Ms. Geil worry thimerosal might cause autism or other brain damage.
Brands of mercury-free flu shots:
Fluzone. Sanofi Pasteur. Inactivated virus. Mercury-free version, approved for adults and for children ages 6 months and older.
FluMist. MedImmune. Live virus. Mercury-free, approved for most adults (not pregnant women and some others) and for children ages 2 and older.
Fluarix. GlaxoSmithKline. Inactivated virus. Trace thimerosal, approved for adults ages 18 and older.
For more information and to locate mercury-free shots:
Allegheny County Health Department. 412-687-ACHD
State Department of Health. 1-877-724-3258.
Ms. Geil called pediatricians, primary care doctors, her obstetrician, the Visiting Nurses Association, and flu clinics at grocery stores and drug stores around her hometown of Mars, and then around greater Pittsburgh. Many people didn't know what she was talking about when she asked for thimerosal-free flu shots.
Others, such as several of her children's pediatricians, dismissed her worries and resisted her attempts to get preservative-free shots. And when she went through a similar process again this month, one doctor even said worries about a link between thimerosal and autism were "hogwash," according to Ms. Geil.
Her practice, the pediatrician said, refused to order mercury-free shots on principle because that would be admitting concerned parents were right to worry.
"For me, the verdict was still out," said Ms. Geil, who ultimately got two mercury-free flu shots from a relative's primary care doctor and transported them in an ice-packed cooler to her children's pediatrician. "I'm told as a pregnant woman not to eat tuna because of the mercury in tuna -- although I know it's a different kind -- so why would I want to put it into my body and my children's bodies even if a doctor is telling me it's OK? Why would I want to take that chance?"
Officials at the Centers for Disease Control and Prevention, which most doctors look to as a guide for their treatment policies, say thimerosal is safe and that the risk of serious complications from the flu is much greater than the risk, if any, of complications from thimerosal.
More than 200,000 people are hospitalized each year from flu-related illnesses, and about 36,000 people die from flu-related complications, according to the CDC. During the 2003-04 flu season, 157 children -- about 60 percent of whom were under the age of 5 -- died from the flu. Last year, about 60 children died.
While it's important for high-risk people such as young children, the elderly and their caregivers to get an annual flu shot, the CDC takes no position on whether consumers should get the version with or without thimerosal, according to spokesman Curtis Allen. If patients are concerned about mercury in the shots, they should ask their doctors for the mercury-free version, he said.
"As consumers, if the patients demand a product, providers would recognize that," Mr. Allen said. "At the same time, we're neutral on that issue because there is no scientific evidence that there's a causal relationship between thimerosal and autism."
Some doctors and public health agencies, however, have bowed to parents' concerns in recent years and begun ordering mercury-free flu shots.
The Allegheny County Health Department, for instance, has ordered 200 preservative-free doses for children this year, although it has none this year for pregnant and breastfeeding women because of previous lack of demand. Last year, the health department ordered about 1,000 thimerosal-free adult shots but did not publicize the mercury-free vaccines. Many went unused.
The state Department of Health also has ordered mercury-free doses for poor and uninsured children who visit its clinics.
But most parents take their children to pediatricians, not a county health department or state clinic, to get an annual flu shot. And years after thimerosal was removed from most children's vaccines as a precaution, many of those doctors are still ordering versions of flu shots that contain the chemical.
Children's Hospital, for instance, orders both versions to offer patients a choice, according to spokesman Marc Lukasiak.
For providers, mercury-containing pediatric vaccine shots are about $4 per dose cheaper than mercury-free versions, and they also are easier to store.
Both versions of the flu shot must be kept refrigerated. But while mercury-free versions of the vaccine are produced in bulky single-dose shots, the mercury-containing vaccine is kept in vials that contain 10 doses, allowing more vaccine to be stored in less space.
Because they are used more than once, such vials can be contaminated by bacteria and funguses. Thimerosal has been used since the 1930s as a preservative for such multi-use vials of vaccine.
And while many doctors say there is no reason to go through the extra hassle of ordering and storing preservative-free flu shots and the CDC continues to stand by the use of thimerosal, public health officials have worked to remove the preservative from most other childhood vaccines.
In 1999, the U.S. Public Health Service and the American Academy of Pediatrics asked drug makers as a precaution to voluntarily reduce or eliminate thimerosal in the other vaccines routinely given to children. Other vaccines in the recommended childhood immunization schedule, such as those for whooping cough, tuberculosis and diphtheria, have been free of mercury since 2002.
And in a study released Sept. 26 and published in the New England Journal of Medicine, researchers did find a possible connection between boys receiving high doses of mercury from vaccines and developing motor and verbal tics. Such tics can be symptoms of autism or other neurological problems.
The potential connection had been seen in two previous studies and "might merit more consideration," Dr. Anne Schuchat, director of the National Center for Immunization and Respiratory Diseases, said during a CDC teleconference call with reporters on Sept. 26.
Other studies have suggested that the mercury in thimerosal might act as a trigger for neurological problems only in certain people.
A 2004 study by researchers at Columbia University's Mailman School of Public Health found that a strain of mice that is genetically vulnerable to mercury developed autism-like symptoms such as delayed growth and social withdrawal when injected with thimerosal.
As a result of concerns about the preservative's possible side effects, California, Delaware, Illinois, Iowa, Missouri, New York and Washington have banned flu vaccines containing thimerosal. All children's vaccines in the United Kingdom are thimerosal-free.
But in spite of such questions, most doctors and public health officials say pregnant women, children between the ages of 6 and 59 months, and other high-risk people should get a flu shot each fall even if it contains mercury.
But if the mercury-free shots are difficult for consumers to find, the problem isn't adequate supply, according to Patty Tomsky, a spokeswoman for Lyon, France-based pharmaceutical company Sanofi Pasteur.
It's doctors' unwillingness to order them, she said.
The company makes preservative-free Fluzone, the only mercury-free vaccine approved for children as young as 6 months old. Sanofi Pasteur will make from 10 to 12 million doses of mercury-free flu vaccine this year, with most of that produced as shots for children, she said.
But many of those shots, she said, will be destroyed after this year's flu season -- just as they are every year.
"We've always had excess production, so you can see the disconnect there," Ms. Tomsky said.
Correction/Clarification: (Published Oct. 29, 2007) People interested in finding a thimerosal-free flu shot can call the state Department of Health at 1-877-724-3258. This article as originally published Oct. 24, 2007 gave an incorrect number.
Amy McConnell Schaarsmith can be reached at 412-263-1760 or firstname.lastname@example.org .