By Matt Jones

Britain's insects are mostly fairly benign, but a few can bite, sting or otherwise irritate walkers, and sometimes this can have more serious consequences. So, swot up with our practical advice to keep yourself and others safe on summer rambles, plus a handy spotters' guide to potentially problematic pests. 

Sometimes the smallest countryside creatures can cause the biggest annoyance. A sting or bite can be unpleasant and painful, and for people with allergies or sensitivities, the effects could be serious - even life-threatening. Evidence suggests insect bites and stings are becoming more common in the UK - so make sure you're prepared when you go walking.  

 

Don't bug me!  

Insect bites tend to be seasonal, partly because biting creatures are more active in summer, but also because we often wear clothes that leave more skin exposed in the warmer months. Stick to long-sleeved base layers and trousers (see Gear on Test, p66, for suggestions) to guard against bites and stings, and choose lightweight, wicking fabrics to stay cool and comfortable. Hiking boots and longer socks also provide more protection than low-cut walking shoes or sandals.  

Apply insect repellent to exposed skin before you head out, topping up throughout the day. Products containing at least 30% DEET (diethyltoluamide) are most effective, and proven safe. (Government advice is that up to 50% DEET is safe for those who are pregnant or breastfeeding, and for babies older than two months.) Repellents that use natural oils such as citronella are also popular. Avoid strongly scented toiletries, which can attract insects.  

If you're leading a group walk, make sure you're aware if anyone has allergies or sensitivities to bites and stings. And if someone carries an adrenaline auto-injector pen, find out how and when to use it.  

Dense vegetation, stagnant water and cafes with outdoor seating are insect hot spots, so plan a route that avoids these if possible. When stopping for refreshments, avoid sitting near leftover food or overflowing rubbish bins, which inevitably attract wasps.  

If you do encounter buzzing insects, stay calm and move away slowly. Don't wave your arms around or swat - insects are more likely to bite or sting when they feel threatened. 

 

Bites and stings  

Immediate treatment  

General guidance is to first inspect the wound site and remove any sting, tick or hairs found in the skin. Then clean the affected area with fresh water or an antiseptic wipe. For swelling, apply a cold compress (such as a BUFF soaked in cold water) or an ice pack for at least 10 minutes. Keep the affected area raised if possible.  

 

Pain relief  

Paracetamol or ibuprofen can help, but check for allergies first. For itching, ask a pharmacist about antihistamine tablets or creams such as crotamiton or hydrocortisone. Again, application of a cold compress or ice pack can help reduce swelling.  

 

When to seek medical advice  

If the sting or bite is near the eyes or in the mouth or throat, contact your GP or call NHS 111. Monitor other bites and stings, and seek advice if there's no improvement within a few days or if your symptoms get worse. Be vigilant for signs of infection: increasing redness or swelling, pus, feverish or flu-like symptoms, or swollen glands.  

 

When to get emergency help  

Call 999 for an ambulance if you notice signs of a serious allergic reaction (anaphylaxis) such as wheezing or difficulty breathing; a swollen face or throat; nausea or vomiting; a fast heart rate; dizziness or feeling faint; difficulty swallowing or loss of consciousness.  

 

Spotters' guide 

Wasps and hornets  

There are about 9,000 species of wasp in the UK, but only a handful of these tend to bother us. A wasp or hornet sting causes sudden sharp pain, usually followed by redness and swelling, which can last a few hours and may be painful and itchy. Sometimes a minor allergic reaction may follow, causing irritation for up to a week. A few people experience anaphylaxis (see 'When to get emergency help', above) - in which case, call an ambulance.  

Hornets are about twice the size of a common wasp and buzz very loudly. There is one native European type and an invasive type, the Asian hornet. These are slightly smaller than European hornets and have a dark abdomen with a single yellow band. They have bright-yellow tips to their legs, while native hornets have dark legs.  

There were 78 confirmed sightings of Asian hornets in 2023, nearly all in South and East England, and there is concern about their predatory impact on native insects. If you spot one, try to take a photo, then report it to Defra at alertnonnative@ceh.ac.uk or via the free Asian Hornet Watch app.  

 

Bees

  

A bee sting feels similar to a wasp sting, but the sting will often be left in the wound. To remove it, don't pinch the sting with your fingers or tweezers, but instead use a hard edge, such as the side of a bank card. Bee stings can cause pain, redness and swelling for a few hours. As with wasp stings, some people may have a mild allergic reaction that lasts up to a week. Anaphylaxis can also occasionally occur (call 999 if so).  

 

Midges, gnats and mosquitos 

These small, flying, biting insects are found across the UK, with midges a particular menace to hillwalkers in Scotland. They're typically most prevalent from mid-May to early September, in warm, damp places such as bogs and moorland. Their bites leave small red dots or lumps on the skin, which are infuriatingly itchy and may cause swelling. To avoid being bitten, don't venture out at dawn and dusk when they're at their most active. Try to walk in bright sunshine or breezy, exposed locations, which they don't like. You can normally walk faster than they can fly, so keep moving! They prefer dark clothes, so dress 'light and bright'. Cover your skin, consider wearing a head net and apply a proven insect repellent. Smidge and Jungle Formula are popular, while some swear by Avon Skin So Soft oil spray.  

 

Horseflies and deer flies

  

Horseflies - known as 'clegs' in Scotland and parts of northern England - are larger than midges or mosquitos and tend to have brightly coloured or patterned eyes. Many species live near ponds, rivers and streams. Farms are also a hot spot as these flies are attracted to cattle and horses. Horsefly bites are painful because the creatures have serrated mouthparts that break the skin and draw blood. These mandibles are powerful enough to bite through some fabrics, and tend to leave an open wound that can be prone to infection. The bite will usually be red and raised. You may also experience a localised rash, swelling and puffiness. If these symptoms persist or worsen, see your GP.  

Deer flies - known as 'keds' in Scotland - tend to appear in August and September. They have long wings and large, flat bodies, with grippy, clawed legs that crawl into hair and clothes. On landing, they shed their wings, then go in search of a blood meal. Their bites can be very itchy, though you'll normally feel them wriggling before they reach your skin. They're not easy to swat, squash or brush off, so pinch them between your finger and thumb to remove them.  

 

Ticks

  

Ticks are small, spider-like arachnids, the smallest the size of a poppy seed. They're found in woodland, forests, moorland, grassland, and areas of bracken and bilberry across the UK, and sometimes in urban green spaces. They feed on sheep, deer, squirrels and birds - so whenever these are around, there are likely to be ticks, too.  

Ticks are most active from March to October, but you can pick one up at any time of year. They attach to your skin or clothing and crawl until they find a place to 'dig in', where they remain for a day or two before falling off. Their bites are not usually painful, so you may not realise you've been bitten straight away. They bury their head into the skin to feed, gradually getting bigger as they fill with blood.  

Ticks sometimes carry potentially serious infections, such as Lyme disease and tick-borne encephalitis, so if you find one attached to your skin, remove it as soon as possible. Use a specialist removal tool (available online or from outdoor and pet shops) such as a pair of fine-tipped tick tweezers, a tick card or a tick twister. Grip the tick as close to the skin as possible and pull steadily away from the skin, without squashing it. Clean the skin after removal and apply an antiseptic cream. Never try to burn, smother or crush a tick as this will raise the risk of spreading disease.  

A tick bite can cause a raised red lump, swelling and itchiness. If you've been bitten, be vigilant for signs of Lyme disease. The most obvious is a 'bull's-eye' ring around the bite (see photo, above) though not everyone gets this. If you develop flu-like symptoms after being bitten, contact your GP. A course of antibiotics should clear the infection.  

Tick-borne encephalitis is very rare in the UK. It has similar symptoms to meningitis: severe headaches, a stiff neck and pain looking at bright lights. Other neurological symptoms could include seizures, sudden confusion or changes in behaviour, weakness or loss of movement in the arms and legs, facial drooping, changes in vision or slurred speech.  

'To protect yourself against tick bites, stick to paths and avoid dense vegetation,' says Jolyon Medlock, head of medical entomology at the UK Health Security Agency (UKHSA). 'Wear clothing that covers your skin, perhaps lightly coloured, so you can spot ticks on you and brush them off. Consider using insect repellent, too.'  

Change or brush down your clothes straight after your walk, and check children and dogs. Ticks seek out moist, warm areas of the body - often in folds of skin. So, for the next few days, check your body in the shower or when getting dressed.  

Find more UKHSA advice and resources on ticks at bit.ly/UKHSA_TickResources.  

 

Caterpillars

Most caterpillars in Britain aren't dangerous. The main exception is the invasive oak processionary moth caterpillar: its tiny hairs hold toxins that are harmful to people and animals, causing skin rashes and irritating the eyes and throat. Oak processionary moth caterpillars have so far only been found in London and the South East. They're active from May to July and often move in arrow-headed, nose-to-tail processions, with one leader and subsequent rows several caterpillars abreast. They live and feed almost exclusively on oak trees. If you find them, or spot one of their white silken nests, report it to your local authority or the Forestry Commission. If one gets on your skin, use tweezers or a pen to remove it. Don't try to brush it off, as it will release more hairs. Rinse your skin with running water, allow to air dry (don't towel dry), then use sticky tape to strip off any leftover hairs. Remove contaminated clothes and wash at a high temperature. See your GP or a pharmacist for treatments to help relieve itching.