You are correct that Asian lady bugs can cause inhalant allergy (1). Both respiratory symptoms and angioedema have been associated with Asian lady bug allergy (2). At least 2 proteins have been isolated showing strong binding to specific-IgE and cross reactivity with Blatella germanica, the German cockroach (1). These are outside insects but swarm and ‘invade’ buildings during the late fall to avoid exposure to cold weather. Thus, the allergy tends to be seasonal with symptoms worsening during the fall and winter. If your patient exhibits symptoms throughout the year, thorough cleaning to remove dead lady bugs and cockroaches should be considered. Immunotherapy would likely be beneficial but there is no commercial extract available for testing or treatment. I am not aware of any data showing whether small particle filters make any difference.
In summary, there are no specific therapies to offer your patients with Asian ladybug allergy. I think this problem would respond to immunotherapy if an appropriate extract were available. As for other options, you may wish to investigate cockroach avoidance as this may be a modifiable allergen with which cross reacts with the Asian ladybug.
1. Nakazawa T, Satinover SM, Naccara L, Goddard L et al. Asian ladybugs (Harmonia axyridis): A new seasonal indoor allergen. J Allergy Clin Immunol 2007;119:421-27.
2. Davis RS, Vandewalker ML, Hutcheson PS, Slavin RG. Facial angioedema in children due to ladybug (Harmonia axyridis) contact: 2 case reports. Ann Allergy Asthma Immunol 2006;97:440-42.
I hope this information is of help to you and your practice.
All my best.
Dennis K. Ledford, MD, FAAAAI