What is Skeeter syndrome? When a mosquito bite is more than just an itch

What is Skeeter syndrome?

Skeeter syndrome is a large local reaction to a mosquito bite caused by the immune system reacting to proteins in mosquito saliva.

A normal mosquito bite can cause a small, itchy, raised area of skin. With Skeeter syndrome, the reaction is more severe. The affected area can become very swollen, red, warm, and itchy, and the reaction can sometimes cover a large area of skin.

Skeeter syndrome is sometimes described as a mosquito bite allergy.

What causes Skeeter syndrome?

Skeeter syndrome is caused by a strong immune response to substances in mosquito saliva.

When a female mosquito bites, it injects saliva into the skin. This helps the mosquito feed but can also trigger an immune response. For most people, this causes a small, itchy, swollen area around the bite.

For people with mosquito hypersensitivity, the immune response is much stronger. This causes more inflammation, itching, and swelling, resulting in the larger reaction seen with Skeeter syndrome.

What does Skeeter syndrome look like?

Skeeter syndrome tends to cause a much stronger reaction than a typical mosquito bite, with the most common sign being a large area of swelling and redness around the bite.

The reaction typically develops within hours of the bite and may become increasingly noticeable over the following day. Symptoms usually take several days to settle.

Skeeter syndrome vs a normal mosquito bite

The main differences between a typical mosquito bite and Skeeter syndrome are:

How common is Skeeter syndrome?

Skeeter syndrome appears to be more common in children than adults, although adults can also develop it.

People who have repeated exposure to mosquitoes may also develop different patterns of sensitivity over time.

Although Skeeter syndrome is sometimes described as rare, large reactions to mosquito bites are known to occur.

© Heather Ainsworth

"After years of being bitten by mosquitoes without any serious problems, I developed Skeeter syndrome at the age of 30. Until then, I had no idea that you could develop such a strong reaction to mosquito bites.

Within 24 hours, a bite on my arm had become increasingly swollen and hot to the touch, and I began to feel unwell with flu-like symptoms. I rang 111 who advised me to see a pharmacist.

I was treated with oral corticosteroids, which helped to reduce the swelling, and after 7 days the reaction and discolouring finally improved.

I’d never experienced anything like it before, and I was surprised to learn that I had developed such a strong sensitivity to mosquito bites.”

- Heather Ainsworth, SEO Manager and Author at Patient.

Is Skeeter syndrome dangerous?

Skeeter syndrome itself is usually not dangerous, although the swelling and itching can be severe and uncomfortable.

However, mosquito bites can occasionally trigger a more widespread allergic reaction, including anaphylaxis. This is very uncommon but can be life-threatening.

How is Skeeter syndrome treated?

Treatment for Skeeter syndrome depends on how severe the reaction is.

More severe reactions may require stronger treatment. A healthcare professional may prescribe a short course of oral corticosteroids or, in some circumstances, administer corticosteroid treatment.

You should avoid scratching as it can break the skin and allow bacteria to enter, resulting in a secondary infection such as cellulitis. This will need to be treated with antibiotics.

When to seek medical help for Skeeter syndrome

Call 999 or go to A&E immediately if you develop difficulty breathing, swelling of the mouth or throat, difficulty swallowing, severe dizziness, fainting, or other symptoms suggesting anaphylaxis.

If you are unsure whether your symptoms require urgent assessment, NHS 111 can provide advice.

Can Skeeter syndrome be prevented?

The most effective way to prevent Skeeter syndrome is to avoid getting mosquito bites.

There are several measures which can help reduce your risk.

Key points

• Skeeter syndrome is a severe reaction to a mosquito bite that can cause extensive swelling, redness, warmth, and intense itching around the bite.

• Most cases are not dangerous and can usually be treated with antihistamines, topical corticosteroids, and other treatments to relieve symptoms.

• The best way to prevent Skeeter syndrome is to avoid mosquito bites using insect repellent, protective clothing, and other bite-prevention measures.

• Seek emergency medical help after a mosquito bite if you develop difficulty breathing, swelling of the mouth or throat, dizziness, or fainting.