Whether it's for business or pleasure, travel is supposed to be an enjoyable experience. But these days, taking a simple getaway is riskier than you think.
That's because when you enter a hotel room, you never know what kind of critters entered the room before you. Not people. Critters.
At first, opera singer Alison Trainer didn't feel the bed bugs when she stayed at a Phoenix hotel, but she woke up in the middle of the night and saw them.
"They were all over the bed and the comforter and the pillows and I pulled the sheets off and they were just everywhere," she said.
Trainer ended up with about 150 bites and 23 scars.
"It's not safe - what happened to me was not safe," she said.
Bed bugs are smaller than your fingernail, only come out at night, and are very flat -- until they feed on humans.
"They're like little vampires, like stealth feeders at nighttime," said Michael Raupp, an entomology professor at the University of Maryland. "You're asleep. They crawl into your bed and you may not be able to feel them."
To check for bed bugs, experts say to pull back the sheets and look for the rust-colored stains that bed bugs leave. You should also scrutinize the mattress seams and use a flashlight to check behind the headboard. If you put your luggage on a rack to keep it off the floor; you will reduce the chances you'll bring bedbugs home with you.
But there are smaller organisms lurking in hotel rooms as well: germs. Experts say it's like sharing a room with thousands of strangers and their germs. Hotel faucets and sink bottoms are moist areas where E. coli sometimes collects. Hotel floors can harbor athlete's foot germs for up to three months.
Chuck Gerba, a microbiologist at the University of Arizona, says the virus is causing huge problems within the travel industry.
"They can usually survive several days, to weeks, compared to other types of viruses," Gerba said.
One solution is to keep your socks on instead of going barefoot. Also, use a disinfectant on germ hot spots like the TV remote, light switches and the phone.
ABC News' "Primetime" previously went to 20 well-known hotels in New York, Miami, Houston and Los Angeles armed with a black light. The light revealed dried semen on bedspreads and urine stains on the bedroom walls.
"If it isn't clean, then the hotel has got a problem, because word-of-mouth is terrible advertising," said Joe McInerney, president and CEO of the American Hotel and Lodging Association.
The American Hotel and Lodging Association says hotels have become more proactive about keeping rooms clean and safe by switching from bedspreads to duvet covers that get washed between guests; they are also scheduling regular pest control services.
"It's one of the fundamental things that we provide the guest: a clean, sanitized room so they can have a great experience," McInerney said.
There's another hotel hazard even more invisible than bedbugs and germs -- carbon monoxide.
Late last year, a 26-year-old man died in a Florida hotel room after a boiler beneath the room released the odorless, colorless gas. A few states do require carbon monoxide detectors in hotels, but most don't require hotels to install the detectors in your room.
Travelers can use a few things to protect themselves: any kind of disinfectant, slipper socks to protect your feet and a mini-flashlight to help you search for bedbugs.