Read below about mosquito bite, including causes, treatment options and remedies. Or get a personalized analysis of your mosquito bite from our A.I. health assistant. At Buoy, we build tools that help you know what’s wrong right now and how to get the right care.

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Mosquito Bite Symptoms

Mosquito bites can put a real damper on the fun of picnicking, camping, and being outdoors in general. These tiny insects are hardly large enough to be seen, especially at night, but their bites are somehow very irritating and itchy and can even transmit serious illness.

If a mosquito bite becomes unusually swollen, reddened, and sore, the condition is called "skeeter syndrome".

Characteristics:

  • Mosquito bites leave small red bumps on the surface of your skin.
  • These bumps are very itchy. This is due to your skin's allergic reaction to the saliva which the mosquito injects as it bites.

Duration:

  • The bump usually appears within a few minutes of being bitten.
  • Mosquito bites may take a few days to subside.

Who is most often affected by a mosquito bite?

  • If you've never been bitten by a mosquito before – or a different type of mosquito happens to bite you – you may not develop the itchy bump. That's because the itching and swelling are caused by an allergy to the mosquito's saliva. The sensitivity is triggered by the first bite and the allergic reaction happens on second and subsequent bites.
  • A severe allergic reaction, or "skeeter syndrome" also known as papular urticaria, can include swelling and redness of the bite along with hives, fever, and swollen lymph nodes. Skeeter syndrome is usually found in children.

Where in the world are mosquito bite symptoms most common?

  • Mosquitoes can breed in any place that has stagnant water.
  • Tropical and subtropical regions are most likely to have disease-carrying mosquitoes.

When is a mosquito bite most likely to occur?

  • Mosquitoes don't like direct sunlight. They are most prevalent at dawn, dusk, night and in deep shade, especially near damp areas and standing water.
  • These insects are attracted to your warmth, your sweat, and the carbon dioxide on your breath.

Is a mosquito bite serious?

  • Ordinary mosquito bites are annoying, but not dangerous.
  • An allergic reaction to the bites or a secondary skin infection from scratching, may need medical care.
  • The extreme allergic reaction known as anaphylaxis, or any symptoms of the diseases that some mosquitoes carry, require immediate medical attention.

Mosquito Bite Causes Overview

Many conditions can have the symptom of itchy red bumps on the skin and may be mistaken for mosquito bites. The most common are those involving bites from other insects; allergic reactions to plants that you've touched, or reactions to foods you've eaten or medicines you've taken.

It's important to know whether or not you have a mosquito bite or some other condition, since some mosquitoes carry bacteria, viruses, and parasites.

Most common cause types:

  • Mosquito bites may be confused with bed bug bites. Bites from mosquitoes tend to be scattered individual bumps, while bedbug bites are blotchy, reddened areas of skin that are both burning and itchy.

Less common cause types:

  • Touching certain plants, such as poison ivy, can leave itchy red bumps.

Rare & unusual cause types:

  • Allergies to foods or medicines may show up as hives (itchy red swellings) on the skin.

Depending on what part of the USA or wherever else in the world you live, several important and potentially very dangerous illnesses are transmitted by mosquito bites and include dengue fever, West Nile virus, other forms of encephalitis, malaria, Chikungunya, Zika virus and yellow fever.

6 Potential Mosquito Bite Causes

Disclaimer: The article does not replace an evaluation by a physician. Information on this page is provided as an information resource only, and is not to be used or relied on for any diagnostic or treatment purposes.

  1. 1.Infected Mosquito Bite

    Mosquito bites are very common. They often cause itchiness and redness.

    Usually clears up within a week.

    Rarity:
    Common
    Top Symptoms:
    fever, mosquito bite, spreading redness around mosquito bite, warm mosquito bite
    Symptoms that always occur with infected mosquito bite:
    mosquito bite
    Urgency:
    Self-treatment
  2. 2.Mosquito Bite

    Mosquito bites are very common. They often cause itchiness and redness.

    Usually clears up within a week.

    Rarity:
    Common
    Top Symptoms:
    mosquito bite
    Symptoms that always occur with mosquito bite:
    mosquito bite
    Symptoms that never occur with mosquito bite:
    fever, muscle aches, vomiting, loss of appetite
    Urgency:
    Self-treatment
  3. 3.West Nile Virus

    West Nile virus (WNV) is an infectious disease. People who get WNV usually have no symptoms or mild symptoms. The symptoms include a fever, headache, body aches, skin rash, and swollen lymph glands.

    Lasts a few days to several weeks, and usually goes away on its own.

    Rarity:
    Rare
    Top Symptoms:
    fatigue, headache, nausea, muscle aches, diarrhea
    Symptoms that always occur with west nile virus:
    mosquito bite
    Urgency:
    Primary care doctor

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  4. 4.California Encephalitis

    Encephalitis is an inflammation of the brain. California Encephalitis is a particular strain of virus first discovered in California.

    Indefinite

    Rarity:
    Rare
    Top Symptoms:
    fatigue, new headache, being severely ill, feeling confused and not making sense while talking, stiff neck
    Symptoms that always occur with california encephalitis:
    feeling confused and not making sense while talking, new headache, being severely ill
    Urgency:
    Hospital emergency room
  5. 5.Japanese Encephalitis

    Severe symptoms can be caused by viral brain infection.

    Potentially chronic, lifelong condition

    Rarity:
    Rare
    Top Symptoms:
    being severely ill, fever, new headache, vomiting, stiff neck
    Symptoms that always occur with japanese encephalitis:
    being severely ill
    Urgency:
    Hospital emergency room
  6. 6.St. Louis Encephalitis

    Saint Louis encephalitis virus (SLEV) is transmitted to humans by the bite of an infected mosquito. Most cases of SLEV disease have occurred in Eastern and Central states.

    Indefinite

    Rarity:
    Rare
    Top Symptoms:
    fatigue, nausea or vomiting, being severely ill, new headache, fever
    Symptoms that always occur with st. louis encephalitis:
    being severely ill
    Urgency:
    Hospital emergency room

Mosquito Bite Treatments and Relief

Seek immediate treatment in the emergency room or call 911 if:

  • You have symptoms of anaphylaxis, which is a severe, sudden, life-threatening allergic reaction that includes difficulty breathing and widespread hives on the skin.
  • You have symptoms such as fever, pain, joint swelling, intense headache, and/or extreme fatigue along with the bite. These may indicate any of several serious diseases or parasitic infections known to be carried by mosquitoes and transmitted through their bite.

Schedule an appointment for:

  • Symptoms of "skeeter syndrome," which is a more serious allergic reaction to the bite and includes large swellings or blisters at the site of the bite.
  • Symptoms of skin infection from intense scratching of the bite, such as tender, painful swelling of the bite with redness and pus.

Remedies that you can try at home:

Most of the time, a mosquito bite is just an annoyance that will fade after a few days. In the meantime, you can try applying cold-water packs, ice packs, or a paste made of cold water and baking soda to the bites. Follow the cold pack with over-the-counter medications that can help stop the itch. Sometimes oral antihistamines can ease the symptoms, or even prevent them before you go anywhere known to harbor mosquitoes.

Prevention:

  • Wear light-colored "sun block" clothing. The insects aren't attracted to the light color and can't pierce through the tightly woven fabric.
  • Use of insect repellent, such as DEET, when outside in mosquito-infested areas will help prevent bites in the first place, along with removing all standing water and using mosquito netting if sleeping outdoors.

FAQs About Mosquito Bite

Here are some frequently asked questions about mosquito bite.

Why does a mosquito bite cause swelling?

When a mosquito bites an individual to drink his or her blood, it injects its saliva. Within its saliva is a compound that keeps the blood that it is drinking from clotting, which would both stop the insect from drinking blood and possibly kill the insect. The body has a mild local allergy to this compound and will develop swelling around the site of the bite and itching from the allergic reaction.

Can mosquito bites cause swollen lymph nodes?

No, generally mosquito bites do not cause swollen lymph nodes. Illnesses transmitted by mosquitoes, however, like yellow fever, malaria, west nile virus, and tularemia will cause swollen lymph nodes. This does not mean that if you have a mosquito bite and swollen lymph nodes you have one of these illnesses. These diseases are endemic to certain areas within the United States and the globe, so you are at not risk if you are not within one of these areas.

Can a mosquito bite become infected?

Yes, a mosquito bite can become infected. Generally, un-altered mosquito bites do not get infected, but after scratching or "unroofing" a mosquito bite, it is possible to expose it to germs and cause an infection. It is best to avoid scratching mosquito bites. There are a series of different lotions, creams, and anti-allergy medications than can treat itchiness associated with mosquito bites.

Why is my mosquito bite not healing?

Mosquito bites generally heal within 7 days of forming. If your mosquito bite is not healing, it may have become infected or it may not be a mosquito bite at all. You may also have multiple bites in the same place, or over time if you are in an area with many mosquitoes. If you have an itchy bump that does not heal after 12–14 days, you may want to seek medical evaluation.

What are the differences between a mosquito bite and a spider bite?

A mosquito bite is an easily recognizable non-painful, itchy welt that can be any shape depending on the angle of insertion of the mosquito's saliva. A spider bite, depending on the spider, may have a similar pattern. Spider bites may be itchy, but are most concerning when they are painful or cause tissue death or systemic symptoms like dizziness, nausea, loss of consciousness, or severe bodily pain. Spiders that are very dangerous and poisonous include the back, brown and red widow spiders, brown recluse spider and several others.

Questions Your Doctor May Ask About Mosquito Bite

  • Q.Any fever today or during the last week?
  • Q.Have you experienced any nausea?
  • Q.Do you have a rash?
  • Q.Have you lost your appetite recently?

If you've answered yes to one or more of these questions, try our mosquito bite symptom checker to find out more.

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Mosquito Bite Symptom Checker Statistics

  • People who have experienced mosquito bite have also experienced:

    • 6% Feeling Itchy or Tingling All Over
    • 5% Headache
    • 4% Nausea
  • People who have experienced mosquito bite were most often matched with:

    • 45% Infected Mosquito Bite
    • 30% Mosquito Bite
    • 8% West Nile Virus
  • Source: Aggregated and anonymized results from visits to the Buoy AI health assistant (check it out by clicking on “Take Quiz”).

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