Asian Lady Beetle Infestation: Not Ladybugs, and They Bite

Identification: Asian Lady Beetle (Harmonia axyridis)

• Variable color: orange, red, tan; 0–19 spots.
• Distinct "M" or "W" mark on white pronotum.
• Aggregates in huge numbers on/in buildings in fall.
• Yes, they bite (pinch) and release foul-smelling yellow fluid (reflex bleeding).

Why They're Inside

They overwinter in wall voids, attics, cracks. Warm winter days or indoor heat trigger activity. Vacuuming 50–75 daily indicates a large wall/attic population.

Professional Treatment Required

• Not a DIY job—requires wall void dusting, attic treatment, exterior perimeter spray.
• Timing: late summer/early fall before entry.
• Find a local pest control company with specific experience in Asian lady beetle management.

Immediate Relief

• Vacuum (empty bag outside immediately).
• Seal interior cracks (windows, baseboards, outlets).
• Use light traps in dark rooms.

Key Point

They are beneficial outdoors (aphid predators) but a significant nuisance indoors. Professional exclusion and treatment is the only reliable solution.