Ladybugs are often seen as harmless, beneficial insects, valued as natural pest controllers. These small beetles can, on occasion, bite humans. While bites from most native ladybug species are rare, some, particularly the invasive Asian lady beetle, are known to do so.
When Ladybugs Bite
Native ladybugs generally do not bite humans. Bites most often involve the multicolored Asian lady beetle (Harmonia axyridis), an introduced species brought to control agricultural pests. Asian lady beetles possess mandibles, or chewing mouthparts, typically used for consuming soft-bodied insects, but they can use these to bite human skin. The sensation of a bite is often described as a mild pinch or a sharp, momentary sting. While it may cause minor irritation, it typically does not break the skin or cause bleeding.
Asian lady beetles may bite for several reasons. They might bite if they feel threatened or handled carelessly. During colder months, as they seek warmth and shelter indoors, their need for moisture and food increases, leading them to bite. They may also mistake human skin for a food source or seek moisture during dry periods.
Identifying Asian Lady Beetles
Differentiating between native ladybugs and Asian lady beetles can be helpful. Native ladybugs are typically a vibrant red with black spots. Asian lady beetles can vary in color from orange to red or even yellow, and may have varying numbers of spots or no spots at all. A key identifying feature is a distinct black “M” or “W” shaped marking on the white area behind its head.
What to Do After a Bite
Ladybug bites are generally not dangerous and do not transmit diseases or pose significant health risks to humans. A typical bite mark appears as a small, raised red bump, which usually resolves within a few hours.
Cleaning the affected area with mild soap and lukewarm water reduces the risk of infection and removes irritants. Applying a cold compress can help alleviate any mild swelling or discomfort. Over-the-counter anti-itch creams or antihistamines can provide relief if itching or irritation persists. Although rare, some individuals may experience an allergic reaction, with symptoms such as persistent redness, swelling, itching, hives, or, in severe cases, respiratory issues. If these more pronounced symptoms occur, or if the bite area shows signs of infection like increased pain, warmth, or pus, seeking medical attention is advisable.