You might want to sit down for this -- or maybe not. This is a story about germs on public seats, and just how common and hazardous they might be.
When "Good Morning America" learned that Bay Area Rapid Transit commuter train seats in San Francisco had recently tested positive for all sorts of bacteria, our first reaction was, "Eeeeuuuww!"
And our second reaction was: Is it just the BART seats, or are all public seats germ factories? So we decided to go visit BART and test every seat we sat in along the way.
Click HERE to see the rest of our results and to get tips for warding off germs.
Our journey began with a single swab -- on the seat of my car in Washington, D.C. -- and ended 3,000 miles away in San Francisco. Along the route, my producer and I swabbed every seat we came into contact with.
We tested the airport waiting area, the plane itself, the back row of a movie theater and a restaurant in the heart of San Francisco's Chinatown, where a creepy coincidence made us think we'd find germs for sure.
More on that later.
The Dirty Dozen?
When we were done, we'd gathered samples from 12 targets anyone could encounter on a trip -- the seats in a car, taxi, airport, airplane, rental car, restaurant, hotel lobby, hotel room, movie theater, park bench and toilet seat. Then, finally, BART itself. Would they be the dirty dozen?
Bacteria build-up on the cloth seats in San Francisco's commuter trains had been a "sticky" point for riders for a long time.
One rider said she avoids the seats at all costs, adding that she'd have to be "dead tired" to sit down on the train.
"The fabric covers are really filthy," said another rider, while a third noted, "I might think twice about sitting down."
BART spokesman Linton Johnson said passengers seem to overlook the fact that it's people who bring bacteria on to the trains.
"When you have 350,000 tushes on these seats, it's going to get a little bit of bacteria on them, you know?" he said.
That's why BART provides hand sanitizer at some stations, and why every night, BART employees swap out the very worst seats. Every year, the system spends about $600,000 dollars on dry cleaning.
And now, it's time for the results of the tests on the samples we gathered.
We sent our samples to New York University's microbiology department to be analyzed by a germ guru, Dr. Philip Tierno, the director of microbiology and immunology at the NYU Langone Medical Center.
"There were so many organisms on these seats that I would say that they were never cleaned or rarely cleaned, and that is something to be reckoned with," Tierno said.
Nearly 28 percent of the seats contained traces of E. coli.
More than half, 52 percent, of the samples showed indications of fecal matter.
But BART wasn't one of them. Other not-so-bad seats from our experiment?
My car. Phew! The hotel and the toilet seat. That's right. No E. coli where you'd expect and accept it.
Remember the restaurant in Chinatown where we predicted we'd find bad bacteria? We thought we would because, as we were finishing our lunch, a health inspector department inspector asked us to leave. They locked the doors and closed the restaurant after we left.
Turns out the restaurant had cockroaches, but no significant bacteria. Go figure. The restaurant has since taken care of the problem and re-opened.
It's time now for the doozies.