Is It OK If a Mosquito Bites You? Risks & Prevention

Medically Reviewed on 9/26/2022
Is It OK If a Mosquito Bites You
Mosquito bites can sometimes spread diseases

Mosquito bites, while annoying, are typically harmless and resolve on their own after a few days. However, mosquito bites that occur in areas where malaria, yellow fever, and dengue are common may be more dangerous.

In some cases, mosquitoes can transmit diseases. When biting an infected person or animal, a mosquito picks up a virus or parasite and can then transmit that virus or parasite to you through its saliva.

What are common symptoms of mosquito bites?

Mosquito bites are itchy bumps that occur when a female mosquito punctures your skin and feeds on your blood. When a mosquito bites, it injects saliva into your skin. Proteins in the saliva cause a mild immune response, resulting in the characteristic itching and bump. 

Symptoms of mosquito bites may include:

  • Puffy, white, or reddish bump that may appear a few minutes after the bite
  • Hard, itchy, reddish-brown bumps that appear a day or so after the bite
  • Small blisters
  • Dark spots (may look like bruises)

Although symptoms usually go away on their own after a few days, a mosquito bite can occasionally cause more severe reactions, especially in people with weak immune systems. These symptoms may include:

Children have stronger reactions than adults because many adults have been bitten by mosquitoes throughout their lives and have grown desensitized. Some people become less sensitive to mosquito saliva after repeated exposure. However, others may develop allergic reactions. Symptoms of an allergic reaction may include:

If you have a severe allergic reaction to a mosquito bite, seek medical attention. 

Contact your doctor if mosquito bites appear to be accompanied by more serious symptoms, such as fever, headache, body pains, or evidence of an infection.

When are mosquito bites dangerous?

Mosquitoes have the ability to transmit diseases to humans. Diseases caused by mosquito bites account for millions of deaths every year. Some of the most dangerous mosquito-borne diseases include the following:


According to the WHO, malaria threatens 40% of the world's population. Malaria is transmitted by the Anopheles mosquito and can cause severe fever and chills.

If you are going to an area where this condition is common (such as sub-Saharan Africa, India, or the tropics in general), talk to your doctor about whether malaria preventive medications are needed. 

Yellow fever

Yellow fever is most common among Americans who go to tropical countries of Africa, and Central and South America. It is characterized by fever, headache, muscular pain, vomiting, and, in rare cases, jaundice.

According to the WHO, there is a vaccination to prevent the sickness, and a single injection provides lifelong protection. 


Zika virus has been associated with microcephaly, a birth condition in which an infant's head is smaller than usual. Aedes aegypti mosquitoes spread the Zika virus. People who have already been bitten by infected Aedes mosquitoes are immune to it, restricting its spread. 

West Nile

West Nile virus can be found across the U.S. Most infected people exhibit no or few symptoms. If people become aware of the illness, the symptoms will be flu-like (fever, headache, and body aches). The body will normally fight off the virus on its own, without therapy. 

West Nile virus can cause encephalitis and meningitis, which can be fatal in rare cases.


Although the same mosquito species that causes Zika spreads dengue, people in the U.S. are seldom in danger unless they travel outside the country.

Dengue fever is a primary cause of death in tropical and subtropical climates. If you reside in or are visiting a dengue-endemic area, it is best to avoid mosquito bites if possible; there is no vaccination to prevent the infection.


This virus, which is also transmitted by the Aedes aegypti mosquito, can cause high fever, headaches, and joint discomfort that can last years. Unfortunately, there is no way to prevent or treat chikungunya. 

St. Louis encephalitis

This rare virus causes meningitis or encephalitis. Less than 1% of people infected with the virus exhibit any symptoms at all, with the vast majority staying undetected. 


Ringworm is caused by a fungus. See Answer

How can I prevent mosquito bites?

The most effective way to avoid mosquito-borne illness is to avoid mosquito bites. The Centers for Disease Control and Prevention has the following recommendations:

  • Use repellent: Use insect repellent when you go outside. Longer-lasting protection is provided by repellents containing DEET, picaridin, IR3535, and some products containing oil of lemon eucalyptus and para-menthane-diol.
  • Wear proper clothing: When mosquitoes are most active, wear long sleeves and pants. Some mosquito species are active between dusk and dawn. Others, such as the Aedes species mosquito that transmits Zika, are active during the day.
  • Window screens: Repair window and door screens. If available, use air conditioning.
  • Remove standing water: Remove standing water from containers such as flower pots, gutters, buckets, pool covers, pet water dishes, discarded tires, and birdbaths.

How to treat mosquito bites

If a mosquito bite does not cause a severe allergic reaction, you can treat it at home:

  • Warm water and soap: Cleanse the affected area gently with warm water and soap. Baking soda and water can also relieve itching.
  • Ice: Apply an ice pack or a frozen bag of vegetables over the bite to reduce swelling and inflammation.
  • Over-the-counter antihistamines: These can help manage swelling and itching.
  • Over-the-counter hydrocortisone or anti-itch cream: These can relieve symptoms such as itching and inflammation.

Although it may be difficult to not rub or scratch the area where you were bitten, the more you scratch it, the worse the reaction will be. Your nails carry bacteria, and breaking the skin with your nails can result in an infection.

Although mosquito bites can often heal without treatment, sometimes within a few days, they can cause complications. Seek immediate medical attention if you experience severe symptoms as a result of the bite. 

Medically Reviewed on 9/26/2022
Image Source: iStock image

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