Ladybug allergies are on the rise, as masses of the farmer-friendly beetles find their way "home" to get in out of the cold, researchers say.
“During fall, they come inside houses to hibernate, giving rise to increasing complaints of home infestations,” says Kusum Sharma, MD, of the University of Louisville School of Medicine in Kentucky.
Her new survey shows that in some places, as many as 50 percent of people say they’re allergic to ladybugs.
If not brought under control, “ladybug infestation poses a potential health hazard as it continues to spread throughout the United States,” she says.
The new research on ladybugs -- actually, Asian ladybugs, or Harmonia axyridis -- was presented at the annual meeting of the American Academy of Allergy, Asthma, and Immunology meeting.
According to Sharma, Harmonia axyridiswas introduced from Asia in the 1970s and early 1980s in some Eastern and Southeastern states by farmers seeking to control aphids and other agricultural pests. Now, however, the Asian ladybug is gradually replacing the native species. In fact, they’re all over, from “Wisconsin and Missouri to Georgia and New England,” says Takuya Nakazawa, MD, of the University of Virginia in Charlottesville.
Itchy Eyes, Runny Nose Common Symptoms
For the study, Sharma and colleagues anonymously surveyed 99 people, asking when the beetles invaded their homes, what symptoms they developed, and how much allergy medication they used.
Of the total, half said they were allergic to the beetles, and 19 percent reported that they developed symptoms on direct contact. The most common symptoms: itchy eyes, runny nose, sneezing, and rash.
Eighty percent of participants said ladybugs hit their homes in the fall, 60 percent said in spring, and 67 percent said in winter. During the seasonal infestations, 31 percent said they had to reach for extra allergy medication.
“Patients with spring, fall, and winter allergies should be asked about ladybug infestation,” a previously unrecognized cause of symptoms, Sharma says.
David W. Goetz, MD, an allergy specialist in Morgantown, W.Va., agrees. His research shows that ladybug allergies affect people of all ages and is as common as cockroach and cat allergies.
Goetz reviewed approximately 1,400 skin prick tests. Twenty-one percent of the tests were positive for ladybug sensitivity, compared with 24 percent for cats, 27 percent for cockroaches, and 40 percent for dust mites.
“Increased research into ladybug allergy is paramount for future patient care,” he says.
In the meantime, what should you do if you see ladybugs taking up residence in your house? Reach for the vacuum, the experts say.
By Charlene Laino, reviewed by Louise Chang, MD
SOURCES: American Academy of Asthma, Allergy and Immunology 2006 Annual Meeting, March 3-7, 2006, Miami Beach, Fla. Kusum Sharma, MD, University of Louisville School of Medicine, Kentucky. Takuya Nakazawa, MD, University of Virginia, Charlottesville. David W. Goetz, MD, Morgantown, W.Va.