In our new Spotlight on Sepsis series, we explore first-hand stories and medical realities behind sepsis: what can lead to it, when someone may need help, and why research is vital to prevention, diagnosis and treatment.
First up: insect bites. Most bites are harmless, but infections can occasionally become serious. In this article, Dr Abi King shares her experience and explains what to look out for.
Dr Abigail King is a medical doctor and award-winning journalist, broadcaster, and author. Having previously practised in Accident & Emergency and Intensive Care Medicine, she now uses her clinical background to communicate complex health, science, and travel stories to global audiences. She is the founder of Inside the Travel Lab and author of Anatomy Explained.
“Even as a doctor, turning back from a dream hike over a minor bug bite felt embarrassing. But when a harmless puncture turns into a life-threatening infection, swift action is everything. Here is what everyone needs to know about insect bites, cellulitis, and the subtle early warning signs of sepsis.”
The Danger You Can’t Always See: We Need to Talk About Insect Bites and Sepsis
It’s often difficult to describe just how beautiful the Alpujarras mountains can be. Rising out of the earth in southern Spain’s Andalusia, they’re a tonic to the dry earth and scorching plains with their villages bursting with figs, plums and blossoms, rainbow tapestries unfurling along their bright white, walls.
But I was looking at something decidedly less beautiful. The puncture of an insect bite and the reddish tinge around it near my ankle.
I felt fine. We were hiking, taking on the steep and dusty tracks that thread between the terraces, opening up the landscape further through the dramatic views of the Sierra Nevada National Park.
I pulled a biro from my backpack, pulled the cap off with my teeth and drew around the red patch. Backpack zipped up, I sped up to rejoin the gang.
But it was no good. An hour or so later, still feeling absolutely fine, the patch, red like sunburn, had spread beyond the biro and was climbing up my calf.
Beneath skies of brilliant blue and the weekend we had all worked hard to reach, I was going to have to turn back. I needed to go to hospital. And, realistically, given where we were, that was not going to be easy.
Insect bites are incredibly common, you don’t need me to tell you that. As the three faces I was travelling with crowded around my unspectacular looking leg, I knew what they were thinking.
Stripping out the inevitable swear words and teeth-clenched frustration, it would be “surely you don’t need to go to hospital for that. I’ve seen worse from crossing my legs for too long.”
Millions of us get stung by insects in everyday encounters every single year and millions of us are absolutely fine.
There are regions of the world where we need to watch out for insect-borne diseases like malaria, dengue, yellow fever, and zika, and I’ve written at length about the measures you need to take to protect against bites in the jungle.
But that wasn’t the case on a simple hike in familiar Spain.
But here’s where I was lucky. I’d trained and worked as a doctor in A&E in the UK and knew that danger doesn’t always look dramatic.
And my friends knew that, too. In spite of the heavy reluctance and my sense of shame in case I turned out to be wrong, we all turned around and started the long walk back.
When we reached medical help, an isolated cabin with a single medical practitioner, the doctor shook his head. Knowing my background by this point, he looked me right in the eye and said seven simple words that I already knew to be true.
“You should not have waited so long.”
Insect Bites and Sepsis
Diseases spread by insect bites are sneaky and subtle. In this case, I had started to develop cellulitis, a bacterial infection of the skin whereby bacteria sneak in via the hole caused by the insect bite. Left untreated, the bacteria can spread through the blood to the bones, joints and other organs, and they can move fast.
Sepsis, a life-threatening condition that occurs when the body’s response to an infection begins to damage its own tissues and organs, claims around 50 000 lives in the UK each year. It’s difficult to say for certain how many of those fatalities started with an insect bite.
But equally sneaky, not all sepsis that comes from insect bites starts with cellulitis, the spreading redness on your skin. There are the tropical and subtropical diseases I mentioned briefly – the dengue, malaria and chikungunya – that we’re thankfully unlikely to run into in the UK.
But bugs can enter the bloodstream without triggering the reaction in the skin first. For Mark Oakes, a mountain biking enthusiast, for example, he first noticed a fever and joint pain a short while after some bites in Epping Forest. He developed sepsis that led to a harrowing time in intensive care where he nearly lost his life.
There’s also Anna Whitehouse, known as Mother Pukka, a parenting celebrity, who recently talked about her life-threatening experiences following a false widow spider bite.
For those who survive sepsis, the journey often doesn’t end when they leave hospital. Many are left living with life-changing physical and psychological effects, including limb loss, post-traumatic stress disorder (PTSD), chronic pain, fatigue and cognitive difficulties.
The Take Home Message
So, how do we keep ourselves safe without driving ourselves (and our hospital services) around the bend by dropping everything and heading to hospital every single time we get one of life’s most common annoyances?
Here’s the plan.
1. Take reasonable prevention against insect bites
If you know that you’re hiking or spending time outdoors, try to wear loose, breathable fabrics that cover your skin as much as possible. If you notice you’re getting bitten, tuck your trousers into your socks (fashion be damned!) as soon as you can.
Take insect repellent with you for hikes or long times spent outdoors.
Extra Protection Against Mosquito Bites
If you are travelling to or through regions of the world with known insect-borne diseases, like malaria or West Nile fever, take extra precautions. You can find a guide on what to pack for the rainforest and jungle conditions here.
Consult a healthcare professional at least eight weeks before your trip to look into vaccinations and antimalarial tablets. If you’ve missed that deadline, it’s still better late than never, so still visit a travel clinic.
Invest in strong DEET insect repellent and consider permethrin soaked clothes.
Consider sleeping beneath a mosquito net and learn the peak times where mosquitoes appear (dawn, dusk, and around still water depending on the type and where you are travelling to.)
2. Learn to spot the signs of an infected insect bite
Pay attention to early signs, even if you feel like you’re overreacting.
Seek urgent medical attention following an insect bite if you have any one of the following:
- Spreading redness on your skin (look closely on darker skin as it’s harder to spot)
- Fever (a body temperature above 38˚C )
- New joint pain
- Feeling generally unwell
- Tongue swelling or trouble breathing (not sepsis related but could be a severe allergic reaction)
As sepsis develops, symptoms worsen. At this point, seeking medical attention switches from urgent to a full on emergency. Do not feel guilty about calling 999 if a person is
- Confused
- Barely responding to someone talking to them
- Has mottled skin
- Can’t breathe properly
And you certainly don’t need to wait for them to have all of those symptoms and signs. Any one is enough to seek emergency care.
3. Have courage if you think a bite may be infected
It can feel intensely awkward to ask for help over something that, in the moment, feels minor.
Get over that and seek appropriate treatment. Every decent doctor alive would rather see something at the point where they can do something about it rather than waiting until someone is critically ill or it is too late. And they would rather see people who turned out to be fine than risk not seeing someone who needed help.
So, yes. Perhaps it started with a simple insect bite or sting. But if it’s moved on, then so should you.
4. But don’t take the blame
You can do everything “right.” You can wear the right clothes, monitor any bites sensibly, know all the warning signs of infection and seek medical attention early but sepsis can still develop in you or someone you love. That’s not your fault. It’s a complicated disease process that we are working to understand. Not only how do insect bites and stings lead to sepsis but how does any event start this cascade of illness.
5. Support research and rehabilitation for sepsis
With eleven million deaths from sepsis each year and up to half of survivors needing ongoing physical and psychological support, we urgently need further research into the diagnosis, treatment and prevention of sepsis. Around 10% of all cases are thought to start from infection in the skin or soft tissues.
Sepsis Research have outlined six different ways that research can help and our work has supported the development of NHS England’s Modern Service Framework for Sepsis. That includes work on antibiotic resistance, vaccinations, faster diagnosis and more.
For example, the GenOMICC study is investigating whether certain genes make some people more susceptible to sepsis than others, with more than 44 000 samples contributed from around the world.The DALI-2 Study focuses on correct antibiotic dosage in intensive care and the STTAR-BacPro Project led by the University of Glasgow aims to safely block harmful bacterial toxins released when antibiotics attack infections.
Donate to fund life-saving research >
6. Spread the word about infected bug bites
Share this article across social media or just talk to people you know. We don’t mind how you do it but the more people who know about how bug bites become infected, the better.
Signs of an Infected Bug Bite At a Glance
What does an infected insect bite look like?
An initial insect bite may have a small area of redness around it and a raised centre. If the redness around the bite continues to spread or if you see white or yellow discharge coming from the centre, it’s a clue that it may be infected. You should seek medical treatment that day. Bear in mind that on darker skin, you may need to also look for shades of purple, grey or darker brown – but you still need to take action in the same way.
How to treat an infected insect bite
The treatment of infected bites depends on how far things have progressed and how fast they are progressing. It typically involves antibiotic treatment, either as pills or injections, and may also involve other drugs and intravenous fluids. You can try an over-the-counter antihistamine and ice pack to relieve the itching but do not delay accessing urgent care while doing these things.
Medical Disclaimer: This article is for informational and educational purposes only and does not constitute individual medical advice. While the author is a medically trained doctor, reading this content does not establish a doctor-patient relationship. If you suspect you have an infected insect bite, cellulitis, or sepsis, or if you are experiencing a medical emergency, please seek immediate assessment from a qualified healthcare professional or call emergency services (999/112).