Mosquito Bites

Mosquito bites are small, raised bumps on the skin resulting from a female mosquito feeding on human blood.

Mosquitoes are small, flying insects. They have six legs and long mouthparts — used to feed on blood and nectar. Only female mosquitoes feed off of blood. Three different types of mosquitoes exist in various parts of the world: Aedes, Culex and Anopheles.

Often, mosquito bites don’t cause any lasting harm. They cause mild annoyance and irritation for a short period. However, mosquitoes are dangerous because they spread diseases that can be fatal.

Where are mosquitoes found?

Mosquitoes are often near water. They lay their eggs in shallow, stagnant water. The eggs are usually in marshes, ponds, lakes, children’s pools, the inside of tires, birdbaths and other containers with shallow water.

Why do mosquitoes bite?

Mosquitoes bite and suck blood for reproduction. Though male mosquitoes only eat flower nectar, female mosquitoes eat both flower nectar and blood. The females need the protein in blood to develop eggs.

What happens when a mosquito bites you?

Mosquitos have a long mouthpart (proboscis) that extends far beyond their heads. It looks like a tiny needle. When a mosquito bites you, it uses this mouthpart to pierce your skin, suck your blood and secrete saliva into your bloodstream.

Why do mosquito bites itch?

When a mosquito secretes saliva into your bloodstream, your body registers the saliva as an allergen. Your immune system then sends the chemical histamine to the area where the mosquito bit you to remove the allergen from your body. Histamine is what causes your mosquito bites to itch and swell. Most people have a mosquito bite allergy.

How do mosquitoes spread disease?

Mosquitoes spread disease through their bites. Mosquitoes are vectors (living things that carry diseases between animals and humans). Vectors often carry infections through blood. Many of the creatures classified as vectors are bloodsuckers. Other vectors include ticks, fleas and sandflies.

When a mosquito bites, it not only sucks blood but secretes saliva. This saliva enters your blood. There is an exchange of fluids between the mosquito and your bloodstream. An infected mosquito has fed off a person or animal with the disease. It then passes the infection on when it bites. Mosquitoes often feed in a method called sip feeding. Sip feeding means that the mosquito doesn’t just suck all of the blood it needs from one source — it takes multiple meals from multiple sources. Unfortunately, this exposes more people to infection.

What types of diseases can be spread by mosquito bites?

• Chikungunya: Found in Africa, North and South America, Asia, Europe and the Indian subcontinent, chikungunya is a virus transmitted by the Aedes aegypti mosquito. Symptoms of this virus include fever, joint and muscle pain, headache, nausea, tiredness and a rash.
• Zika: Found in Africa, North and South America, Asia and the Pacific region, Zika is a virus transmitted by the Aedes aegypti and Aedes albopictus mosquito. Once a person is infected, the virus can be transmitted from person to person through sex. Zika symptoms include a mild fever, headache, joint and muscle pain, a skin rash and irritated eyes. If a pregnant person is infected with Zika, the virus can impact the developing fetus.
• Dengue: Found in Africa, North and South America, Asia and Europe, dengue is a virus transmitted by the Aedes aegypti mosquito. The symptoms of dengue are similar to the flu. Other symptoms include fever, headache, joint and muscle pain and nausea.
• West Nile virus: Found in Africa, North America, West Asia, Europe and the Middle East, West Nile virus is transmitted by the Culex mosquito. West Nile virus can be fatal. Symptoms of the most severe version of the virus can include headache, fever, a stiff neck, confusion, coma, convulsions and weakness of the muscles.
• Malaria: Found in sub-Saharan Africa, malaria is a virus transmitted by the anopheles mosquito. Symptoms of malaria can include fever, headache and vomiting. Malaria can be fatal.
• Yellow fever: Found in Africa and Latin America, yellow fever is a virus transmitted by the Aedes aegypti mosquito. Symptoms of yellow fever can include fever, headache, muscle and back pain, lack of appetite and vomiting. Yellow fever can be fatal.

Who is at risk of being bitten by mosquitoes?

Mosquitoes bite anyone. However, some factors might prompt mosquito bites. These include:

• Wearing dark-colored clothing.
• Wearing perfume.
• Blood type.
• Body temperature.
• Visiting a region with active mosquito-transmitted diseases.
• Spending time near stagnant water.