In some severe cases, though, medical help may be necessary.

Spiders

It is not typical for non-venomous spiders to leave a bruise after biting.

Wasp Stings

Stings from wasps (including hornets) are painful.

Child’s legs with bruises and bug bites

sarune zurba / Getty Images

Mosquitos

Mosquitosare well known for their red welts and itching.

Skeeter syndrome is not typically a life-threatening allergy.

Other symptoms include:

Skeeter syndrome lasts 3 to 10 days.

If your symptoms worsen or last longer, seek medical attention for a possible skin infection.

When a tick embeds in your skin, the site may appear red or purple.

After the bite, a skin rash is common, especially in the case of atick-borne illness.

If you experience any of the above symptoms after youve spent time outdoors, speak to a healthcare provider.

What Is Anaphylaxis?

Anaphylaxis is a life-threatening allergic reaction that requires immediate medical attention.

For example, when amosquitosucks your blood, it injects saliva into your skin.

Treatment

Usually, bug bites are a minor nuisance, but sometimes they can be more concerning.

Allergies

Around 15% of fatalities fromanaphylaxis(severe allergic reaction) are from venom allergies.

Allergies to stingsand bug bites require immediate medical attention.

This kind of infection is more likely when bitten by venomous spiders.

Necrotizing infections are dangerous and require immediate medical attention.

Symptoms include:

Venom Injury

Not all spider bites can make you sick, but some can.

Be aware of what diseases may be acquired where you live or places to which you travel.

Insects that may cause bruising include mosquitos, ticks, bees, and spiders.

If any of these warning symptoms accompany your bug bite bruise, seek medical attention right away.

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Johns Hopkins Medicine.Insect stings.

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The American Academy of Allergy, Asthma & Immunology.Skeeter syndrome defined.

Centers for Disease Control and Prevention.Symptoms of tick-borne illness.

Centers for Disease Control and Prevention.Mosquito bite symptoms and treatment.

Childrens Hospital of Philadelphia.Bee and wasp stings.

American Academy of Dermatology Association.Tips to prevent and treat bug bites.

2014;134(6):1318-1328.e7.

doi:10.1016/j.jaci.2014.08.018

National Library of Medicine.Skin infections.

Johns Hopkins Medical.What is necrotizing soft tissue infection?

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