The bloodsucking pests, which are not known to spread disease but can cause great mental anguish with their persistent and fast-growing infestations, have rapidly multiplied throughout New York and many other U.S. cities in recent years.
Health officials and pest control specialists nationwide report surges in sightings, bites and complaints. The Environmental Protection Agency hosted its first-ever bedbug summit last year.
In New York City, the pests have been discovered in theaters, clothing stores, office buildings, housing projects and posh apartments.
The stigma of having bedbugs - whose bites leave itchy red welts - and the elusive nature of the pests make it impossible to fully understand the problem, experts say.
But in 2009, for the first time, Mayor Michael Bloomberg's administration included a question about bedbugs on its community health survey, and it revealed the finding to The Associated Press on Wednesday: More than 6 percent of New Yorkers who responded said they had battled the pests in the last year.
The figure would equal roughly 400,000 adults in the city, the health department said.
Data previously has been limited to government statistics on complaints and surveys of private pest-control companies, which also have reported nationwide spikes.
The Bloomberg administration fielded 537 complaints about the bugs in fiscal 2004. In fiscal 2009, there were nearly 11,000.
"This is happening globally, and I don't think anybody has figured out exactly why," said Daniel Kass, the city's deputy commissioner for environmental health. "So what we're left with is managing them and keeping them from spreading. They're going to be with us for some time."
Bedbugs are about the size of an apple seed and burrow into many more places than beds. They can slip into floor cracks, wall outlets, picture frames, lamps - any tiny space.
People who have bedbugs often never see them. The most obvious signs are bites, blood on bedsheets and their waste, which looks like black pepper. They are known for being extremely difficult to eradicate and can go a year without feeding.
Bedbugs were nearly dormant for decades, and the recent comeback has experts scratching their heads. Some attribute the resurgence to an increase in global travel and the prohibition of potent pesticides like DDT.
New York convened a government advisory board last year to study the problem and make recommendations.
The report said one major roadblock to stopping the bedbug spread is lack of knowledge about prevention and the patchy and sometimes erroneous information about treatment.
"If you have termites, you know how to deal with it. If you see a rat, you know who to call. This is confusing," said City Council Speaker Christine Quinn. "The biggest issue is lack of clarity and not having any actual sense of what the next step is and where you go to get that."
Carol Gittens said she discovered bedbugs in her Brooklyn apartment two years ago and estimates she has spent at least $3,000 replacing her things.
"We had to throw everything out - mattresses, clothes," she said.
The apartment was thoroughly cleaned and she thought she had eliminated them. But a neighbor recently reported she has bedbugs, and Gittens said she might have them in her apartment again.
The high cost of throwing out infested belongings and hiring exterminators contributes to bedbugs' spread, officials said. Many people, particularly those with low incomes or in public housing, cannot afford to do what it takes.
Acting on the report's recommendations, New York City said Wednesday it was re-appropriating $500,000 of health department money to begin the first phase of a bedbug battle plan, which is mostly concentrated on information, outreach and the creation of an entomologist-led bedbug team.
Some of the money will go toward creating an online bedbug portal where New Yorkers can find information about avoiding the pests as well as how to treat their homes. The city already has a rat-information portal.
Many people are unaware they have the bugs, officials said, and end up spreading them by carrying them on their clothing or discarding personal items that have the bugs.
Travelers also need to be more vigilant, the city says.
"Everyone has got to get used to the idea that they have got to check for them periodically," Kass said. "People who travel should look at the rooms they're staying in. They should check their clothing. There are good preventive measures."
Experts recommend looking for bugs with a bright flashlight, and using a hot hair dryer to flush them out of hiding places and cracks.
Bedding, linens, curtains, rugs and clothes from infested homes must be washed in hot water. Mattresses, furniture and floors must be vacuumed, and vacuum bags should be immediately disposed in sealed plastic bags. Hiring a certified exterminator to apply pesticides is also recommended.
Officials also said the city would adopt the report's recommendation of working to establish protocol for disposing of infested furniture and other personal items.
The report also suggested more work should be done by agencies that serve lower-income New Yorkers, and public housing infestations should be addressed more quickly. But at a time when the city is cutting services and shrinking its job force to save money, those goals are likely not immediately achievable.