[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Microbiology](https://durgical.com/en/microbiology/) › [Ectoparasites](https://durgical.com/en/microbiology/groups/ectoparasites/) › Cimex lectularius and Cimex hemipterus

# Cimex lectularius and Cimex hemipterus

- Parasite
- For completeness

Flat, reddish-brown insects that hide in beds and bite at night. Bites itch and disturb sleep, but bed bugs are not known to spread disease.

Updated Nov 13, 2026

Also called: bed bugs, chinches de cama

## Quick facts

**Type**
Parasite · [Ectoparasites](https://durgical.com/en/microbiology/groups/ectoparasites/)

**Gram / shape**
Oval

**Spread**
Carried in luggage · They come out at night

**Causes**
Cimicosis · Papular urticaria and

**Treatment**
Bites

On this page

- The basics Key points
- At a glance
- Morphology
- Transmission
- Life cycle
- Memory aid
- What the colours mean

- Clinical Virulence factors
- Diseases it causes
- Clinical picture
- Diagnosis

- Treatment Treatment
- Prevention

- Study Test yourself

- Connections Connections

## Key points

- Bed bugs bite at night and hide by day in mattress seams and cracks.
- Not known to transmit disease to people.
- Bites in rows or clusters on exposed skin; diagnosis needs finding the insect.
- Each nymph needs a blood meal to moult; adults survive months without food.
- Control: integrated pest management, heat and laundering; insecticide resistance is common.

## At a glance

**Shape**
Oval, flat, reddish-brown body that swells and darkens after feeding

**Family**
Cimicidae

**Type**
Wingless blood-feeding insects (Hemiptera), temporary ectoparasites

**Size**
About 1–7 mm depending on stage

## Morphology

- Flat body that fits into mattress seams, bed frames, cracks and behind sockets.
- Beak-like piercing mouthparts folded under the head.
- Nymphs are paler, almost translucent, and turn red after a meal.

## Transmission

- Carried in luggage, clothing, used furniture and mattresses between homes, hotels, hostels and shelters.
- They come out at night, feed for a few minutes on sleeping people, then hide again.
- Infestation has nothing to do with dirt: it follows travel and moving belongings.

**Reservoir:** Human dwellings, hotels, shelters, dormitories and public transport; Bats and birds for related species

### Isolation precautions

What the care team adds to standard precautions.

- Standard

## Life cycle

- The female lays a few eggs a day in cracks and seams, glued to surfaces.
- Eggs hatch in about one to two weeks into nymphs that look like small adults.
- Each of the five nymph stages needs a blood meal before moulting.
- Adults feed every few days and can live many months.
- Adults and nymphs survive several months without feeding, so empty rooms stay infested.

## Virulence factors

- Saliva with anaesthetic and anticoagulant substances: the bite is not felt.
- Reactions are hypersensitivity: many people have none, others itchy wheals.
- Infestations cause insomnia, anxiety and social stigma.
- Widespread resistance to common insecticides.

## Diseases it causes

- Cimicosis: itchy bite reactions, often in rows or clusters
- Papular urticaria and, rarely, severe allergic reactions including anaphylaxis
- Secondary bacterial infection from scratching

## Clinical picture

- Itchy red papules or wheals on exposed skin (face, neck, arms), often in a line or cluster.
- Reactions may appear one to several days after the bite.
- Several people sleeping in the same place are affected; insomnia and anxiety are common.

## Diagnosis

- Clinical picture plus finding the insect: live bugs, shed skins and eggs in mattress seams and furniture.
- Rusty or dark spots of blood and faeces on sheets and mattresses; a sweet, musty odour in heavy infestations.
- Bites alone cannot confirm bed bugs: mosquito and flea bites look alike.

## Treatment

Bites: avoid scratching, antiseptic care, topical corticosteroids and oral antihistamines for itch; emergency care for anaphylaxis. Infestations need professional integrated pest management, not repeated self-spraying.

Drug class only; doses and regimens are set by the clinician from the current guideline.

In Pharmacology:

- [Hydrocortisone](https://durgical.com/en/pharmacology/hydrocortisone/)
- [Cetirizine](https://durgical.com/en/pharmacology/cetirizine/)
- [Epinephrine](https://durgical.com/en/pharmacology/epinephrine/)

## Prevention

- Inspect beds and luggage when travelling; keep bags off the floor and bed.
- Wash and dry clothing at high temperature after trips or when infested.
- Inspect second-hand furniture and mattresses before bringing them home.
- Mattress encasements, reducing clutter and vacuuming seams and cracks.
- Early detection: small infestations are much easier to control.

## Memory aid

Breakfast, lunch and dinner in a row: three bites in a line, and the waiter hides in the mattress seam.

## Test yourself

Think of the answer, then tap the question to see it.

## Do bed bugs transmit infections to people?

They are not known to spread disease; the problems are itching, allergic reactions, superinfection and sleep loss.

## Where do bed bugs hide during the day?

In mattress seams, bed frames, headboards, furniture cracks and behind wall fittings near where people sleep.

## Why can an empty apartment stay infested?

Because adults and nymphs can survive several months without a blood meal.

## What signs on the bed suggest an infestation?

Rusty blood or faecal spots, shed skins, eggs and live bugs in seams, and a musty odour.

[Add to my cards (4)](https://durgical.app/estudiar/?add=/en/microbiology/cimex-lectularius-and-cimex-hemipterus/)

## What the colours mean

**Gram-positive**
Thick peptidoglycan wall: stains purple.

**Gram-negative**
Thin wall with an outer membrane: stains pink.

**Acid-fast**
Lipid-rich wall (mycobacteria): Ziehl–Neelsen stain.

## Connections

## Related 4

- [Pulex, Xenopsylla and Ctenocephalides](https://durgical.com/en/microbiology/pulex-xenopsylla-and-ctenocephalides/)
- [Sarcoptes scabiei](https://durgical.com/en/microbiology/sarcoptes-scabiei/)
- [Pediculus humanus and Pthirus pubis](https://durgical.com/en/microbiology/pediculus-humanus-and-pthirus-pubis/)
- [Triatomines (Rhodnius prolixus, Triatoma dimidiata)](https://durgical.com/en/microbiology/triatomines/)

[← Back to the group: Ectoparasites](https://durgical.com/en/microbiology/groups/ectoparasites/)

Educational content on microorganisms; not a treatment guide and no substitute for a health professional's advice. No doses are given.

Sources: [About Bed Bugs | Bed Bugs | CDC](https://www.cdc.gov/bed-bugs/about/index.html) (CDC, 2024); [Bed Bugs: Get Them Out and Keep Them Out](https://www.epa.gov/bedbugs) (US EPA, 2025).

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Representative model, for educational purposes only.

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License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/microbiology/cimex-lectularius-and-cimex-hemipterus/