Second of two parts
A decade ago, doctors hailed Rotashield as a miracle vaccine that could save thousands of lives each day. It would fight rotavirus, a nasty bug that causes dehydration so severe it kills more than 600,000 babies each year, mostly in developing nations.
But within months of its release, after a million children received it, the vaccine's makers discovered a rare, dangerous side effect and pulled it from the market.
The Rotashield story has become well-known in the controversy about childhood vaccines. For advocates of vaccination, it shows that the system catches even rare problems and corrects them. But for those who suspect — despite ample science to the contrary — that vaccines cause autism, Rotashield proves that unsafe compounds sometimes make it to market.
"The government is always trying to cover stuff up, just to make more money," said Brandon parent Leesa Davis, who was concerned enough about autism to change the schedule on which her baby received vaccines. "They've said many times that we were safe, and then we weren't, about a lot of things."
But to nationally known vaccine advocate Dr. Paul Offit, Rotashield teaches the opposite lesson.
Researchers realized the vaccine was flawed after about 100 children developed a rare intestinal blockage called intussusception. It occurred in 1 in 10,000 children before Rotashield was pulled in 1999. To Offit, the experience proves that if vaccines caused something as common as autism — occurring in up to 1 in 150 children — scientists would have realized it by now.
"With rotavirus vaccine, (a problem) was found in 100 children, and it was easily picked up," said Offit, director of the Vaccine Education Center at the Children's Hospital of Philadelphia.
It also shows there was no coverup, he said.
"There are those who are convinced there's a conspiracy to sell vaccines, and we're all in it to make money," he said.
But doctors and parents don't always see the world the same way.
Part of the difference is how people perceive danger. Studies show people don't gauge risks well. Unlikely events like shark bites grab headlines, and people may worry more about those remote risks than they do about daily dangers.
"When all that bird flu rigmarole was on the news all the time, people were coming in asking me for Tamiflu, in case they got bird flu," said Tampa pediatrician Marcy Baker. "But they're not getting their flu shot" for the common seasonal virus.
Rarely, vaccines can be dangerous. Most often, reactions are mild, such as soreness or fever. But more serious reactions can occur. In about 3 in 100,000 children, the vaccine for diphtheria, tetanus and pertussis can cause shock and brain inflammation. Another extremely rare risk is allergic reaction.
Most doctors believe the risks of not vaccinating are far greater.
"I understand you might be upset about a 1 in 500,000 chance" of a bad reaction, said Dr. Greg Poland, director of the Vaccine Research Group at the Mayo Clinic. But, he said, compare it to the chance of dying in a car crash. Over a year: 1 in 6,500. Over a lifetime: 1 in 84.
"We try to make cars as safe as we can, but we accept that risk," he said. "It's always a risk-benefit. There is no vaccine that is 100 percent safe for everybody."
To Davis, the Brandon mom, news stories of children who developed autistic symptoms after vaccines scared her enough to give her baby separate shots for measles, mumps and rubella.
"The fact is, there have been people who have had these shots and then their child is changed forever," Davis said. "It can't be purely coincidence."
But most doctors say that it is just coincidence. Autism appears at the same time many children get shots. But studies don't show a link.
"You can have A and B, and they look correlated," said Poland, who helps to set national vaccine policy. "But they're due to separate factors."
He tells this story: After World War II, birth rates in Europe fell. Meanwhile, the stork population took a similar drop. Interesting, yes. Related, no.
Offit says his wife, also a pediatrician, once picked up a needle to vaccinate a child, and the baby had a seizure.
"If she had given the vaccine five minutes earlier, nobody would have been convinced" it was a coincidence, he said. But the baby later was diagnosed with a seizure disorder.
Since the failure of Rotashield a decade ago, researchers — including Offit — have developed a new rotavirus vaccine.
Scientists are monitoring the new vaccine, RotaTeq, and have not found any link to intussusception. A recent study found a dramatic drop in hospitalizations from rotavirus since the vaccine came into use.
Lisa Greene can be reached at firstname.lastname@example.org or (813) 226-3322.