1. Food crumbs and leftovers

Ants love sugar. A single drop of juice, a few crumbs on the worktop or a little syrup left in a glass are enough to attract them.

They locate these food sources using pheromones, chemical scents that they leave behind on their trail to guide their fellow ants.

3. Rubbish bins and poorly cleaned areas

Uncovered rubbish bins, sugary waste, or unwashed pet bowls attract ants. A sweet or greasy smell is enough to trigger an invasion within hours.

5. Seasonal changes

Ants become more active in spring and seek safe shelter when temperatures rise. During periods of rain or intense heat, they may migrate indoors in search of refuge and food.

See also: How to find and get rid of an ant nest?

2. Lemon and citrus fruits

Lemon, grapefruit and orange contain natural acids that disrupt the olfactory system of ants.

➡️ How to do it:

• Change them every two days.
• Squeeze a lemon and pour the pure juice on the entry points.
• Place pieces of citrus peel near cracks and skirting boards.

4. Diatomaceous earth

This natural white powder, composed of microfossils of algae, acts mechanically on insects. It tears the thin waxy layer of their bodies and dehydrates them.

➡️ How to use it:

• Sprinkle it around entry points, under skirting boards, near doors and windows.
• Use food-grade, uncalcined diatomaceous earth (safe for animals).
• Repeat after each cleaning or rainfall.

6. Coffee grounds

Natural, economical and biodegradable, coffee grounds give off a smell that ants hate. As well as acting as a repellent, they enrich your garden soil!

➡️ How to use them:

Sprinkle them around nests, on window sills or in the garden after rain.

2. Insecticide powders

These powders are mainly used outdoors, around nests, terraces, borders or cracks. They work by contact or ingestion and quickly eradicate visible ants.

➡️ Instructions for use:

• Lightly sprinkle the powder on areas where ants travel or at the entrance to the nest.
• Leave to work without watering or sweeping for 24 to 48 hours.
• Repeat after rain if necessary.

⚠️ Precaution: Avoid using the powder in living areas or near animals (toxic if ingested).

4. Slow-release granular bait

The ants carry these products back to the nest, which eliminates the colony at its source.

➡️ Instructions for use:

• Avoid mixing them with repellents (the aim is to attract the ants).
• Place the granules near their trails or around terraces.

Did you know?

An ant nest is home to several castes:

• The queen, the only reproductive member, sometimes lays several thousand eggs per year.
• The workers, which are sterile, take care of transport, food and nest maintenance.
• The larvae and eggs, which grow in protected, ventilated chambers.
• The soldiers, or more robust ants, are responsible for defending the colony.

Some species, particularly Myrmicinae such as the red ant, can have several queens and several thousand individuals.

Inside (house, flat)

An ant nest is home to several castes:

• Ants visible around crumbs, rubbish bins or pet bowls.
• Regular trails near skirting boards, cracks or electrical conduits.
• Ants present at night: they are more active at this time.
• Small particles of wood or dust at the foot of walls or furniture (sign of a carpenter ant nest).
• Practical tip: Place a drop of honey and observe the direction in which the workers return; this will lead you to the anthill.

2. If the nest threatens the garden or animals

A nest can become a nuisance when:

• The ants attack plants to protect the aphids they are raising.
• They settle near feeders, chicken coops or animal bowls, attracted by food.
• They dig under patio slabs or paving stones, causing the ground to lift.

Lemon

Its acidity acts as a natural repellent. Squeeze a lemon and place pieces or juice directly at the entrance to the nest.

➡️ Repeat every two days.

Diatomaceous earth

This 100% natural mineral powder works mechanically by cutting through the thin protective layer of ants. Use biocidal diatomaceous earth that is uncalcined, amorphous, and has a minimum silica (SiO2) content of 90% for greater safety and effectiveness.

➡️ Sprinkle or spray around the nest, under skirting boards, or near kitchen openings.

See also: Diatomaceous earth: an effective solution against bed bugs.

Clean your home regularly

This is the simplest and most effective thing you can do:

• Avoid leaving crumbs, sweet leftovers or pet food bowls uncovered.
• Clean surfaces with soapy water or vinegar.
• Empty and disinfect bins regularly.

The red ant (Myrmica rubra)

The nightmare of hikers and gardeners! Very common in temperate regions, the red ant lives in grassy, damp areas such as forests. Its bite is painful, comparable to a mild burn, and often causes a small red blister that itches for several hours. When it bites, it injects a formic acid-based venom that causes the burning sensation.

What does the red ant look like?

• Where to find it: lawns, gardens, damp meadows, under stones or tree stumps.
• Size: approximately 4 to 6 mm.
• Colour: brownish red, sometimes coppery.
• Appearance: slender body with bent antennae and a visible sting at the rear.
• Behaviour: very mobile, aggressive when its nest is disturbed.

The electric ant (Wasmannia auropunctata)

Less well known than the red ant, the electric ant is nevertheless one of the most invasive and painful species in the world. Native to South America, it has spread to several tropical and subtropical regions, including New Caledonia, Guadeloupe and French Guiana. It was first spotted in France in Toulon in 2022.

Its sting is sharp and burning, comparable to an electric shock lasting 2-3 hours, hence its nickname, the electric ant. It threatens not only local biodiversity, but also human dwellings, as it settles in electrical sockets, household appliances and wooden structures, sometimes causing short circuits.

What does the electric ant look like?

• Size: approximately 1.5 mm for workers and 4.5 mm for queens
• Colour: brown to orange body
• Where to find it: inhabited areas, sources of heat.

Frequent risk situations

Stings often occur accidentally, in everyday situations:

• Walking barefoot in the grass or on dry ground in summer, without seeing a hidden anthill.
• Stepping on a nest hidden under leaves, stones or grass.
• Sitting or picnicking on infested ground: ants, attracted by crumbs, climb onto skin or clothing.
• Gardening without gloves, handling soil, pots or wood stored near a colony.

Sensations following a sting

• A quick stinging or burning sensation upon contact with the insect.
• Itching in the hours that follow.
• In some cases, swelling or slight blistering that persists for 24 to 48 hours.
• Rarely, a throbbing pain or a feeling of local heat.

Aloe vera gel

Known for its anti-inflammatory and healing properties, pure aloe vera gel is very useful against insect bites.

➡️ Apply a small amount of gel to clean skin and allow to dry in the open air.

It instantly soothes the sensation of heat, reduces marks and promotes skin regeneration..

1. Protect yourself in high-risk areas

When walking, hiking or gardening:

• Wear long clothing (trousers, socks, long sleeves) to protect your legs and feet.
• Wear closed shoes and avoid walking barefoot in the grass.

3. Use natural repellents and insecticides

To repel ants without harsh chemicals, sprinkle a little bicarbonate of soda, diatomaceous earth or white vinegar around the infested areas..

These insects, which feed on human blood, never appear ‘by chance’.

Here are the main causes of bed bug infestations:

• Travel: suitcases and bags brought back from hotels, hostels or accommodation that is already infested.
• Second-hand furniture: mattresses, bed bases, sofas or chests of drawers picked up on the street or bought without checking them first.
• Clothing and textiles: sheets, curtains or clothing stored in infested communal areas or laundromats.
• Mattresses and contaminated items thrown away without precautions
• Moving house: a single bug hidden in a box or piece of furniture is enough to infest a new flat.
• Visits from outsiders carrying bugs on them

Step 1: Report it quickly

The first thing to do is to immediately alert the building manager or property manager. The sooner the problem is dealt with, the more effective and limited the treatment will be. Bed bugs multiply very quickly; an adult female can lay 5 to 10 eggs per day and around 500 during her lifetime. A colony can therefore form very quickly.

It is also important to inform your immediate neighbours (in adjoining flats, above and below) so that they can inspect their homes.

Silence only makes the situation worse and leads to higher costs for the entire building.

Who is responsible in the event of an infestation in a building?

The main task of a co-owners’ association is to maintain and manage the common areas (Article 14 of Law No. 65-557 of 10 July 1965).

If several units and/or common areas are affected by bed bugs, the infestation may be considered a structural problem. In this case, the property manager or landlord is responsible for organising and financing the treatment of the common areas and affected dwellings (unless otherwise explicitly stated in the co-ownership regulations).

See also: Bed bugs in university residences.

For co-owners and tenants

Every resident of the building can reduce the risk of infestation by taking simple steps:

If you suspect an infestation, alert your neighbours and the property manager immediately rather than treating it yourself, as this may cause the bedbugs to spread.

• Regularly inspect bedding: sheets, mattresses, box springs and pillows.
• Check bedrooms for small black spots (excrement), traces of blood or moulted skin.
• Wash textiles (sheets, curtains, covers, clothing) at a minimum temperature of 60°C after travelling or staying in a potentially infested place.
• Avoid picking up furniture, mattresses or bed bases that have been abandoned on the street or in the common areas of the building.

A high turnover of students

University residences and campuses are constantly busy places. Every semester, new French and international students arrive, while others leave their accommodation for internships, university exchanges or to finish their studies. This constant turnover makes it easy for bed bugs to take hold. These small insects can easily be carried in students’ belongings, such as suitcases, clothing and bed linen.

The situation can quickly escalate, as a single bed bug in a room can cause an infestation throughout the entire building.

The start of the school year is a particularly risky time. With holidays and trips abroad, the chances of bringing bed bugs home with you are multiplied. This is especially true since cases of infestation increase in summer.

Insufficient prevention measures

The State owns 82% of university buildings (source). Unfortunately, investment is clearly insufficient.

Landlords, CROUS (the French student housing agency) and higher education institutions have limited resources to implement effective prevention policies. Financial priorities generally focus on routine maintenance, urgent repairs and services for students receiving grants.

As a result, control measures are often taken too late, once the infestation is well established.

The lack of standardised protocols, regular inspections and staff training exacerbates the problem.

Areas to inspect first

Bed bugs hide mainly near their food source and in dark corners. Here are the places to check first:

Bedding:

• Seams and folds in the mattress.
• Slats, gaps and stapled fabric on the bed base.
• Pillows, covers and blankets.

Furniture near the bed:

• Bedside tables, drawers and shelves.
• Cracks in desks, wardrobes and chests of drawers.

Fixed structures:

• Behind skirting boards and cracks in walls.
• Under loose wallpaper.
• In electrical sockets and switches.

Personal items:

• Suitcases, backpacks and folded or stacked clothing.
• Curtains, rugs and decorative cushions.

➡️ Good to know: canine detection is the most reliable and accurate method for detecting bed bug infestations.

Raising awareness among students

Informing students is essential to limit the appearance and spread of bed bugs.

Here is an example of what an effective awareness campaign might include:

☑️ Posters and visual aids in halls, lifts and common areas explaining:

• How to recognise bed bugs and their eggs.
• The main signs of infestation (bites, black spots, traces of blood).
• What to do immediately if you suspect an infestation.

☑️ Information meetings at the beginning of the year:

• Presentation of the risks and consequences of an infestation.
• Advice on how to avoid bringing them back after a trip or stay away from home.

☑️ Practical guides distributed to students:

• Rules for maintaining bedding (regular washing at high temperatures).
• Use of anti-bedbug covers on mattresses and pillows.
• Importance of reporting any suspicions to the manager immediately.

☑️ Digital communication

• Emails and posts on the university’s social media accounts.
• Video tutorials on inspecting rooms and furniture.

Size and shape of eggs

Bed bug eggs are extremely small and difficult to spot.

Here’s how to recognise them:

✅ Size: approximately 1 mm long and 0.5 mm wide, about the size of a pinhead.

✅ Shape: elongated and slightly curved, resembling a small grain of rice, but much smaller and thinner.

⚠️ Caution: to the naked eye, they can be mistaken for light-coloured dust, dandruff or micro-debris.

Where do female bed bugs lay their eggs?

Female bed bugs lay their eggs in strategic locations, close to their food source (your blood) and away from light.

Here are their favourite hiding places:

✅ Mattresses and bed bases: they often lay their eggs in the seams, folds, labels and zips of mattresses, as well as under the fabric of upholstered bed bases.

✅ Headboards and bed frames: cracks in the wood, grooves and gaps in metal or wooden frames are ideal places, especially if they are close to where you sleep.

✅ Skirting boards and cracks in walls: female bed bugs like to lay their eggs in small cracks, behind skirting boards, under loose wallpaper or at the junction between the floor and the wall.

✅ Furniture near the bed: bedside tables, bed frames, shelves and even drawers can harbour eggs, especially in cases of advanced infestation.

✅ Textiles and clothing: although less common, eggs may be laid on fabrics left on the floor or piled up near the bed, as well as on curtains or carpets.

See also: How to recognise a bed bug nest

Heat treatment

High temperatures are the most reliable method for eliminating bed bug eggs.

We therefore recommend using a dry steam cleaner (minimum 120°C). For your information, this type of appliance can be rented from specialist DIY stores.

➡️ Slowly steam all infested surfaces: mattress seams, skirting boards, headboards, upholstered bed bases, cracks. Hold the nozzle 5-10 cm from the surface for at least 2 to 3 seconds to reach the inside of the eggs and kill them.

➡️ Place clothes, bags and small non-washable items in an airtight bag and then directly into the freezer. Please note that a simple freezer compartment is not sufficient; you need a freezer that can actually reach -20°C.

Washing textiles at high temperatures

Wash sheets, covers, clothing and any other machine-washable textiles at 60°C for at least 30 minutes. Bed bugs do not survive at this temperature.

In addition to washing, especially for thick textiles or removable mattress covers, use a tumble dryer on a high heat cycle for at least 30 minutes.

➡️ See also: How to wash your bedding and clothes if you have bed bugs?

✅ Wash bed linen regularly

Change and wash your sheets, pillowcases, blankets and covers at a minimum of 60°C every week if you live in a high-risk area or in an infested building.

Mattresses, box springs and headboards

The seams, folds and corners of mattresses are very popular with bed bugs. This allows them to stay close to their food source (you) at first. If the infestation is not treated, bed bugs will eventually move and create nests further and further away from the bed.

Inspect the edges, seams, zips and the inside of bed bases, where they also lay their eggs.

Another possible hiding place: headboards (wooden, fabric or leather). Bed bugs often leave traces (excrement, eggs, moulted skin) here.

➡️ See also: Bed bugs in a mattress: what to do?

Furniture near the bed

Bedside tables, bed frames, shelves and any furniture near the bed may be infested, especially in cases of advanced infestation. Check every crack and crevice.

Bed bugs love rough textures such as untreated wood.

Clothing and textiles

Be careful with clothes left near the bed! This is a common source of contamination in other homes. Bed bugs can also hide in curtain hems, under rugs and behind picture frames.

➡️ See also: Washing clothes contaminated with bed bugs.

Presence of live and dead insects

You will find bed bugs of all sizes:

• Nymphs (immature stages): translucent to yellowish, measuring 1 to 4 mm.
• Adults: brown, the size of an apple seed (5 to 7 mm).

Presence of eggs

The eggs are tiny (about 1 mm), white and slightly shiny. They are often stuck in clusters to surfaces (seams, wood, cracks) thanks to a waxy substance that makes them difficult to remove.

Presence of exuviae (moulted skins)

Bedbugs moult 5 times before reaching their adult size. You will therefore find small translucent skins in their hiding places.

1) Inspect the bedding first

Start with the bed, as this is the main hiding place for bed bugs.

✅ Remove all sheets, pillowcases and blankets.

✅ Check the seams, folds and labels on the mattress: use a torch to see better.

✅ Examine the slats and bed base, especially if they are upholstered. Bedbugs like to hide under stapled fabric and in cracks in the wood.

3) Inspect at night

Bed bugs are nocturnal insects.

To confirm their presence:

✅ Turn off the lights at night and then turn them back on suddenly to see them moving.

✅ You can also observe their movements on the mattress or even on your body if you sleep for a few minutes with the lights off.

Feel free to use a powerful torch to illuminate dark corners. A magnifying glass can also be useful for inspecting eggs, which are very small and stick to surfaces.

First steps to take

✅ Vacuum with a narrow nozzle and a sealed bag

• Vacuum thoroughly around the nest, eggs, cracks and seams.
• Dispose of the bag immediately in a sealed bag outside to prevent recontamination.

Throw the bag immediately into a sealed bag outside to prevent recontamination.

✅ Wash your sheets and clothes at a high temperature

• For non-washable textiles, use a steam cleaner at 120°C (this equipment can be rented) or place them in the freezer at -20°C for 72 hours.
• Wash all infested laundry at a minimum temperature of 60°C for 30 minutes.

Regularly check areas at risk

✅ Inspect your mattress, bed base and skirting boards every month, especially if you live in a shared building.

✅ Keep an eye on furniture near your bed, curtains, carpets and clothes that have been stored away for a long time without being used.

✅ Be vigilant after travelling or buying second-hand furniture.

In summary, they can:

✅ Spread a natural odour barrier throughout the room or bedding;

✅ Help relieve irritated skin after bites;

✅ Complement a comprehensive treatment for mild infestations.

1. Lavender essential oil (Lavandula angustifolia)

Known for its soothing properties, lavender is also effective against pests. Its floral scent is highly unpleasant to bed bugs. In addition, it calms the itching associated with bites.

💡 How to use it?

Here is a recipe for a lavender repellent spray:

• 500 ml of warm water
• 40 drops of true lavender essential oil
• 10 drops of tea tree essential oil (to enhance the anti-parasitic effect)
• An opaque glass spray bottle
• Shake the bottle well before each use. Spray generously on mattresses, sheets, curtains, bed frames and infested textiles. Avoid direct contact with the eyes and skin.

➡️ Frequency:

Apply morning and evening for 7 to 10 days, then every 2 or 3 days as needed.

3. Clove essential oil

Thanks to its eugenol content, it has powerful pest-repelling properties. Its strong scent acts as a natural barrier against bedbugs.

💡 How to use it?

Here is an anti-bedbug formula based on clove essential oil:

• 500 ml of warm water
• 30 drops of clove essential oil
• 10 drops of lemon eucalyptus essential oil (enhances the repellent effect)
• A sturdy glass or plastic spray bottle

Shake the bottle well before each use. Spray on areas at risk: mattresses, sheets, skirting boards, bed bases, corners of furniture, fabric seams.

➡️ Frequency: twice a day for a week, in addition to a treatment protocol against infestation.

5. Lemon eucalyptus essential oil

Refreshing and powerful, eucalyptus essential oil combines anti-inflammatory (ideal for bites) and repellent properties.

💡 How to use it?

Here is a recipe for a lemongrass spray:

• 500 ml of warm water (preferably distilled)
• 30 drops of lemongrass essential oil
• 15 drops of tea tree essential oil (optional, to enhance the effect)
• An opaque spray bottle

Shake well before each use. Spray on sensitive areas: mattress seams, bed base, skirting boards, underside of the bed, curtains, carpets, etc.

➡️ Frequency: once a day for 7 to 10 days in case of infestation, then twice a week for maintenance.

7. Peppermint essential oil

Highly fragrant, peppermint acts as a powerful repellent against bed bugs and other crawling insects.

💡 How to use it?

Here is a recipe for a natural repellent spray made with peppermint essential oil:

• 500 ml water
• 30 drops of peppermint essential oil
• 10 drops of tea tree essential oil (for its anti-parasitic effect)
• 1 tablespoon of white vinegar or 70% alcohol
• An opaque spray bottle

Shake before each use. Spray on mattress seams, bed bases, skirting boards, curtains and textiles at risk (sheets, sofas, etc.). Avoid direct contact with the skin, especially in children under 6 years of age or pregnant women.

➡️ Frequency: one application per day for 7 to 10 days, then every 2-3 days for maintenance.