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Common Bed Bug

Cimex lectularius

Use cautionCommon

Quick answer

Itchy bites at night; not known to spread disease. Safety level: Use caution.

How to identify the Common Bed Bug

A flat, oval, reddish-brown insect about the size of an apple seed (4-5 mm).
After feeding it swells and turns darker red.
Signs include small dark spots on sheets and mattress seams, tiny pale eggs and shed skins.
Size: 4–5 mm.

Where it lives

Found worldwide in homes, hotels, dormitories and public transport. It hides in mattress seams, bed frames, headboards, sofa cushions and behind skirting boards, and spreads in luggage and second-hand furniture.

Is it dangerous?

Bed bugs feed on blood at night. Bites are often itchy red bumps in lines or clusters, but some people show no reaction. They are not known to spread disease. Scratching can lead to skin infection, and infestations can cause stress and poor sleep.

Not sure what bug you found?

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Children and pets

Check mattresses and luggage after travel.

What to do

Wash bedding on the hottest setting.
Call a professional; they spread fast.

Fun fact

A bed bug can survive months without a meal.

⚠ Call emergency services straight away for trouble breathing, swelling of the face or throat, or a scorpion sting in a child. This page is general information, not medical advice.

Frequently asked questions

How do I know if I have bed bugs?

Check mattress seams and bed frames for live bugs, tiny dark spots and shed skins.

How do I get rid of bed bugs?

Wash and dry bedding on high heat and contact a pest professional; bed bugs are hard to remove alone.

How do I avoid bringing bed bugs home after travel?

Keep luggage off the bed, check the hotel mattress, and wash travel clothes on hot when you return.