This is an I-Heart podcast.

We were talking about the flu shot and how the studies show it doesn't actually work.

In fact, it kills more people than it saves.

Then in 2008, Cheryl Atkinson did a piece on how top vaccine advocates were receiving substantial

funding from pharmaceutical companies.

Years now, parents have wondered if vaccines are linked to conditions like autism and ADD.

Government officials and some scientists say there is no connection and they're often backed by independent experts.

But just how independent are they? You may be surprised at what Cheryl Ackison found when she set out to follow the money.

There's some of the most trusted voices in the defense of vaccine safety.

The American Academy of Pediatrics, every child by two, and pediatrician Dr. Paul Offutt.

But CBS News has found these three have something more in common.

Strong financial ties to the industry whose products they promote and defend.

The vaccine industry gives millions to the Academy of Pediatrics for conferences, grants,

medical education classes even helped pay to build their headquarters.

The totals are kept secret, but public documents reveal bits and pieces.

$342,000 was given to the Academy by Wyeth,

maker of the Numa Cawkel vaccine for a community grant program.

$433,000 was contributed to the Academy by Merck the same year the Academy endorsed Merck's HPV vaccine.

Another top donor, Santa Fe AV Ventis, maker of 17 vaccines, and a new 5-1 combo shot just added to the Childhood Vaccine Schedule last month.

Every child by two, a group that promotes early immunization for all children, admits the group takes money

from the vaccine industry too, but wouldn't tell us how much. A spokesman told us, there are

simply no conflicts to be unearthed. But guess who has been listed as the group's treasurers,

...