What is Asian Ladybug Allergy?

This colorful insect may seek out the warmth of your home.

Asian Ladybugs. Michigan Dept of Agriculture

Asian ladybugs (the scientific name being Harmonia axyridis) were released as a pest-control measure against aphids in many areas of the United States until 1990. These insects began to swarm inside houses in the late fall to protect themselves from freezing weather in the wintertime.

Since then, large populations of Asian ladybugs can be found infesting houses in Wisconsin, Kentucky, Missouri, West Virginia, and along the East Coast to as far south as Georgia.

Typically, rural and suburban homes are more commonly affected than homes in urban settings.

What Problems do Asian Ladybugs Cause?

There have been numerous reports and studies on Asian ladybugs causing allergic symptoms in people, including:

Various methods have been developed by research allergists for diagnosing allergy to Asian ladybugs— these include skin testing to extracts made from the ladybugs to RAST.

How Do Asian Ladybugs Cause Allergy?

Asian ladybugs release an orange-colored fluid as a defensive measure, which has a foul odor. Proteins from this fluid, along with dropping and other body parts, likely become airborne, causing allergic symptoms in susceptible people.

How Common is Allergy to Asian Ladybugs?

In certain areas of the country, such as West Virginia, positive allergy tests to Asian ladybugs in people seeking care from an allergist are as high as 21 percent.

This rate of positive skin tests is nearly as high as positive skin tests to cockroach (27 percent) and dust mite (40 percent) in the same population.

Do Asian Ladybugs Cause Allergy Symptoms Year-Round?

Unlike other common indoor allergy triggers, such as dust mites and cockroaches, Asian ladybugs are present in homes typically from September through March.

Therefore, this may be considered a form of seasonal allergy, similar to pollens.

How are Allergies to Asian Ladybugs Treated?

Avoidance of Asian ladybugs should be attempted, and various methods to reduce the infestation of homes by this insect have been tried. Ensuring that gaps around windows, doors and porches are sealed will reduce the number of ladybugs entering the home. Frequent cleaning of the dead insects should also reduce the number of insect proteins in the home.

Other methods to reduce Asian ladybugs have been suggested by pest control experts, and traps are available to capture the insects once they enter the home.

If allergies do occur, medications aimed at the allergic symptoms can be used in much the same way as treating allergy to pollens, dust mites and pet danders. Allergy shots to Asian ladybugs have been successful, but only experimental at this time.


Albright DD, Jordan-Wagner D, Napoli DC, et al. Multicolored Asian Lady Beetle Hypersensitivity: A Case Series and Allergist Survey. Ann Allergy Asthma Immunol. 2006; 97:521-7.

Nakazawa T, Satinover SM, Naccara L, et al. Asian Ladybugs(Harmonia axyridis): A New Seasonal Indoor Allergen. J Allergy Clin Immunol. 2007; 119: 421-7.

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