European wasp

The European wasp (Vespula germanica) is originally native to Europe, Asia, and North Africa. Where it has been introduced to other regions, it often lacks the natural predators that would keep its numbers in check. In its native range, cold winters mean that usually only the queen survives, but in warmer climates an entire nest can survive through the year, and some nests may contain more than 100,000 wasps. With few predators and favorable weather, the wasp can become an increasing problem in areas where it is introduced.

This insect likes to live around people because of the ready supply of food and drink, particularly sweet items.

Identifying the European wasp#

Physical characteristics include:

• looks similar in size and shape to a bee
• around 15 mm in length (a queen is about 20 mm long)
• a bright yellow body with triangle-shaped markings
• two long antennae
• wings that are folded when at rest

Unlike a bee, which can only sting once and leaves its stinger behind in the skin, the European wasp can sting repeatedly. It also releases a scent chemical (pheromone) that alerts other wasps to attack.

Wasp stings and allergic reactions#

The sting of a European wasp typically causes local inflammation, with symptoms such as:

• burning pain
• a raised lump
• redness

Although they are painful, isolated wasp stings seldom cause serious problems. However, the venom contains toxins that can cause allergic reactions in susceptible people. Around one in 10 people who are stung two or more times become allergic, which means they will have severe reactions to any later stings. The most severe allergic reaction of all is anaphylaxis, which can be life threatening.

Symptoms of a severe allergic reaction may include:

• itchy, burning, or reddened skin
• swelling of the mouth, tongue, or throat
• difficulty breathing or swallowing, or noisy breathing
• abdominal cramps or nausea
• a sudden feeling of weakness, or collapse and unconsciousness
• increased heart rate, palpitations, or chest pain or tightness
• a strange metallic taste in the mouth
• in children, looking pale and floppy

When to seek urgent help#

Call for an ambulance immediately if:

• a child is stung more than 5 times
• an adult is stung more than 10 times
• anyone is stung in the mouth or throat, as swelling there can block the airway
• there is a severe allergic reaction, or a history of an allergic reaction to wasp stings

First aid for less severe stings#

• clean the affected area with soap and warm water
• use a cold pack to reduce swelling and pain
• use pain-relieving medication and creams
• treat prolonged swelling at the site with antihistamines – ask your pharmacist for advice

Be alert for signs of anaphylaxis. Your doctor may advise you to carry a self-injectable adrenaline (epinephrine) auto-injector (for example, an EpiPen) if you have been stung by wasps before.

First aid if allergic to wasp venom#

Anaphylaxis is a life-threatening reaction that can cause death from swollen airways. The following steps are only for use in the event of a severe allergic reaction:

• Call your local emergency number (for example 911 in the US and Canada, 112 across the EU and many countries, 999 in the UK, or 000 in Australia) immediately for an ambulance.
• If breathing stops, begin resuscitation immediately.
• Follow the person’s emergency plan if they have one, and administer their own medication into the thigh.
• Apply a pressure immobilization bandage over the site to restrict the spread of venom, and avoid all unnecessary movement, which helps prevent the venom from entering the bloodstream and lymphatic system.

To apply a pressure immobilization bandage:

• If the sting is not on a limb, firm direct pressure over the site may help.
• Otherwise, apply a firm broad bandage over the site, wrapping away from the heart.
• Wrap the complete limb, from the fingers or toes toward the shoulder or groin.
• Wrap firmly but not so tightly that circulation is cut off.
• Splint the limb, including the joint above and below the sting if possible.
• Do not remove the bandage or splint once it has been applied, and do not use a tourniquet.
• Keep the person as still as possible, and bring transport to the person if at all possible.

It is strongly advised that you attend a first aid course so you can deal with an emergency of this kind. If you have had a severe allergic reaction to a wasp sting, you will need specialist assessment for immunotherapy after your recovery.

Dealing with nests#

It is strongly recommended that you hire a licensed pest control operator to destroy any wasp nests on your property. This is especially important if you have had an allergic reaction to a wasp sting in the past, or if you have never been stung and are unsure of your allergy status.

It can help to locate the nest before you call a pest control operator, as the nest may not actually be on your property. To locate a nest:

• Remember a European wasp may forage for food up to about half a kilometre from its nest, so you may need your neighbors’ cooperation.
• Place food (preferably meat) in a visible outdoor spot.
• Once it finds the food, the wasp will fly almost in a straight line back to its nest.
• If necessary, keep relocating the food until you see the wasp fly into its nest.

Nests are usually built in sheltered locations, such as underground, within retaining walls, in tree hollows, and in holes in walls. The nest looks as though it is made of gray papier-mache.

Reducing wasps around your home#

You can reduce the number of European wasps around your home and lower the risk of stings:

• Don’t leave food, drink, or pet food outside.
• Pick up any fallen fruit.
• Make sure outdoor rubbish bins have tight-fitting lids, and cover compost bins.
• Cover food during a barbecue or picnic.
• Don’t drink straight from a can or bottle outdoors, as it could contain a wasp – use a straw.
• If you see a European wasp, leave it alone; it will only attack if provoked.

A poisons information service may be available in your area, often around the clock, for advice about poisonings, suspected poisonings, bites and stings, mistakes with medicines, and poisoning prevention.

Key points#

• The European wasp can sting repeatedly and releases a pheromone that calls other wasps to attack.
• Isolated stings are painful but seldom serious; however, the venom can trigger allergic reactions, and anaphylaxis can be life threatening.
• Know the signs of a severe allergic reaction, follow first aid steps, and call for an ambulance urgently when warning signs are present.
• Reduce risk by keeping food and drink covered outdoors and by having a licensed pest control operator destroy any nests.

Where to get help#