Worried about bedbugs? Well, now here’s something else to worry about: the pesticides used to kill them, according to federal health officials.

At least 111 people in seven states have gotten sick from being exposed to chemicals used to try to eradicate bedbugs between 2003 and 2010, the federal Centers for Disease Control and Prevention reported Thursday. Most of the cases were mild, and the victims recovered. But an elderly woman with a history of health problems died in North Carolina in 2010. She applied large amounts of insecticides in her home to try to get rid of bedbugs. She also went so far as to put bedbug and flea powder on various parts of her body, the CDC reported.

The other cases were in California, Florida, Michigan, Texas, Washington and New York, with more than half occurring in New York City. The problems commonly occurred because too much insecticide was used, or people failed to wash or change bedding that had been treated. Sometimes, they didn’t know chemicals had been applied, the CDC said. Most of the cases occurred among people in their homes. The most common symptoms were headaches, dizziness, nausea, vomiting and pain and discomfort breathing.

“Although the number of acute illnesses from insecticides used to control bedbugs does not suggest a large public health burden, increases in bedbug populations that are resistant to commonly available insecticides might result in increased misuse of pesticides,” the CDC wrote in its Morbidity and Mortality Weekly Report.

The agency urged greater efforts to alert people to the potential dangers of the substances and suggested people consider other means to control bedbugs and prevent infestations. For example, people should avoid buying used mattresses and box springs, the agency said.