Allergies Animal & Insect Allergies Risks and Prevention of Asian Ladybug Allergy Increased Rates Linked to Seasonal Infestations By Daniel More, MD Daniel More, MD Daniel More, MD, is a board-certified allergist and clinical immunologist. He is an assistant clinical professor at the University of California, San Francisco School of Medicine and currently practices at Central Coast Allergy and Asthma in Salinas, California. Learn about our editorial process Updated on March 05, 2022 Medically reviewed Verywell Health articles are reviewed by board-certified physicians and healthcare professionals. These medical reviewers confirm the content is thorough and accurate, reflecting the latest evidence-based research. Content is reviewed before publication and upon substantial updates. Learn more. by Daniel More, MD Medically reviewed by Daniel More, MD Daniel More, MD, is a board-certified allergist and clinical immunologist. He is an assistant clinical professor at the University of California, San Francisco School of Medicine and currently practices at Central Coast Allergy and Asthma in Salinas, California. Learn about our Medical Expert Board Print Asian ladybugs (Harmonia axyridis) are generally harmless, but some people develop allergic reactions from being around them, touching them, or to their bites. The allergy symptoms reported from exposure to these bugs include allergic rhinitis, conjunctivitis, asthma, and hives. Wahyu Amrullah / Getty Images Causes Asian ladybugs were introduced in the United States in the early 20th century as a means of pest control. While the colorful insects are highly effective at culling aphid populations, they are ill-suited to survive cold temperatures, so they tend to move indoors when it's cold out. By the mid-1990s, the Asian ladybug population in the US had grown to such a size that many rural and suburban communities began to experience severe home infestations. Infestations have been reported all along the East Coast as far south as Georgia and in states like Wisconsin, Kentucky, Missouri, and West Virginia. Scientists have discovered that ladybug "blood" (known as hemolymph), which it instinctively releases whenever agitated, can trigger an allergic reaction in some people. At least two allergens, Har a 1 and Har a 2, have been identified in these ladybugs.A chemical called isopropyl methoxy pyrazine (IPMP) is used by the ladybug to deter predators. The substance has a foul odor (similar to that of wet hay), and it leaves a visible, orangish stain on surfaces and fabrics. In addition to "reflex bleeds," ladybugs can also bite humans. While most people can barely feel the bites, they can sometimes cause localized irritation and an allergic cutaneous (skin) reaction. Frequency In certain parts of the country, such as West Virginia, positive allergy tests to Asian ladybugs are as high as 21%. The rate of positive results is nearly as high as those for cockroaches (27%) and a little more than half that of dust mites (40%) The allergies are considered seasonal as they most often occur in the autumn and winter months. Depending on the region, this can last from September to March. Prevention and Treatment The best way to prevent a ladybug infestation is to seal all cracks and openings that they can crawl through. If you find Asian ladybugs inside your house, use a vacuum cleaner rather than a broom to gather them. Sweeping may trigger a reflex bleed. Be sure to dispose of them quickly, rather than letting them collect inside your vacuum cleaner. And, if you have a strong allergic reaction, consider wearing gloves or a mask as you dispose of them to minimize your exposure. Wash your hands with warm soap and water after you finish handling the bugs and debris. If allergies do occur, they should be treated in the same way as an allergy to dust mites, pollen, or pet dander. This may include the use of antihistamines and other allergy medications. While there is no specific treatment for ladybug allergies, allergy shots have been explored in people who have a positive allergy test result. Was this page helpful? Thanks for your feedback! Sign up for our Health Tip of the Day newsletter, and receive daily tips that will help you live your healthiest life. Sign Up You're in! Thank you, {{form.email}}, for signing up. There was an error. Please try again. What are your concerns? Other Inaccurate Hard to Understand Submit 4 Sources Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. Albright DD, Jordan-Wagner D, Napoli DC, et al. Multicolored Asian lady beetle hypersensitivity: a case series and allergist survey. Annals of Allergy, Asthma & Immunology. 2006;97(4):521-527. doi:10.1016/s1081-1206(10)60944-1 Nakazawa T, Satinover SM, Naccara L, Goddard L, Dragulev BP, Peters E, Platts-Mills TA. Asian ladybugs (Harmonia axyridis): a new seasonal indoor allergen. J Allergy Clin Immunol. 2007 Feb;119(2):421-7. doi: 10.1016/j.jaci.2006.11.633. PMID: 17291858. Botezatu AI, Kotseridis Y, Inglis D, Pickering GJ. Occurrence and contribution of alkyl methoxypyrazines in wine tainted by Harmonia axyridis and Coccinella septempunctata. J Sci Food Agric. 2013 Mar 15;93(4):803-10. doi: 10.1002/jsfa.5800. Epub 2012 Oct 19. PMID: 23079938. Goetz DW. Harmonia axyridis ladybug hypersensitivity in clinical allergy practice. Allergy Asthma Proc. 2007 Jan-Feb;28(1):50-7. doi:10.2500/aap.2007.28.2956. PMID: 17390758. Additional Reading Goetz, W. "Harmonia axyridis ladybug invasion, and allergy." Allergy Asthma Proc. 2008;29(2):123-9. DOI: 10.2500/aap.2008.29.3092.