7 Things You Need to Know About Insect Bites

We spoke to GP and television personality Dr Sarah Jarvis about the things we can do to best protect ourselves wherever we are this summer.

1. Your body reacts to saliva, not the bite itself

We don't really feel it when an insect sinks  its 'teeth' into our skin, but our bodies do react to the bug's spit. Sounds pretty disgusting when you think about it.

"You're not reacting to the bite. But when they bite you, they inject a tiny little bit of saliva. The saliva stops the blood clotting so they can take what they want from you. You don't usually know you're bitten for a little while afterwards, it's not like being stung by a wasp or bee."

Dr Jarvis goes onto explain that the immune system recognises the bug's saliva as a foreign chemical and reacts to it by releasing histamines which causes the redness and itching.

2. Not everyone reacts the same way

Why do some people get bitten and others are saved? Underlying genetic factors are estimated to account for 85 per cent of the reasons why some people appear to be tastier to mosquitoes than others. But it can also depend how long the insect actually bites you for that determines whether you will react to it or not. If there's more saliva in your system, there's a greater chance of an immune response.

"As far as I'm aware there's no evidence it's related to blood type. Though some people have heightened immune responses and those people can be more prone to other allergic reactions too," reveals Dr Jarvis.

3. There's plenty you can do to protect yourself

Getting bitten isn't inevitable if you take precautions. The majority of biting insects are out in the evening, so this is when you need to most vigilant. If you're particularly prone or travelling somewhere warm, make sure your arms and legs are covered up during the evening and you're using mosquito nets when you're sleeping. 

The unfortunate exception though, is the Aedes mosquito which transmits the Zika virus.

"Aedes moquitoes tend to be particularly during the day which makes the much more dangerous. So if you're in the relevant area, not only do you need to cover up with woven clothes during the day, you'll need to use a mosquito spray in the daytime too."

4. 'Natural' insect repellents aren't going to cut it

People are understandably nervous about harsh chemicals in products and might opt for natural-sounding alternatives like formulations containing essential oils, but Dr Jarvis cautions you could be wasting your money.

"There is no question that DEET-containing repellents (such as Jungle Formula) are more effective on the whole in studies. And certainly if you're going a Zika area, you should protect yourself with at least 50% DEET insect spray."

Dr Jarvis points out that as ever, it's a question of risk vs benefit. And most studies show that DEET-containing insect repellents are very low risk for a large benefit. Because these insect repellents are applied on the skin, it's unlikely a harmful amount of DEET will enter your system.

6. Keeping cool is vital

The hotter you get, the more prone to irritation and itching you will be. 

7. Watch for signs of infection

Occasionally your insect bite will have started to heal, but a few days later it'll be worse again. If it's hot, red and filled with pus, this could mean your bite is infected and you might need antibiotics from your doctor. If in doubt, go and see your GP.

"Some people will have a local reaction, whereas others will find that after it's started to get better, it will start to get worse again and it'll get hot, red and angry. If that happens, then you'll need to see your GP," advises Dr Jarvis.

If you have swelling or itching anywhere else on your body after being bitten or stung, or if you're wheezing or have difficulty swallowing, you'll need emergency medical treatment. Dial 999 for an ambulance​.

Via

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