Healthy Living

How to Identify Insect Bites and Stings

Most bug bite symptoms cause itchy or painful red bumps, while others cause welts or blisters. Learn how to identify the most common insect bites and stings.

The cause or severity of insect bites or stings can be determined by the symptoms. Most bug bite symptoms cause itchy or painful red bumps. Other insect bites can cause welts or blisters. The following are some clues of common insect bites:

  • Mosquito Bites: Bites from mosquitoes usually leave itchy red bumps on the skin. In rare cases, their bite may cause a severe allergic reaction. 
  • Bed Bug Bites: Bed bug bites may cause hives or blisters at the site of their bite. Their bite marks are often itchy and red, and may also cause a severe allergic reaction. 
  • Spider Bites: A spider bite may either cause minor or severe symptoms, which may require immediate medical attention. Their bites usually cause pain, swelling, and red skin at the site of the bite. 
  • Flea Bites: The symptoms are usually experienced right away after being bitten by fleas. Flea bites are itchy and leave a red bump with a red halo surrounding it. Their bites are often seen in clusters on the feet, ankles, and lower legs. 
  • Tick Bites: Tick bites leave a skin rash that resembles a bull’s-eye. Ticks may also carry and transmit bacteria that cause Lyme disease
  • Bee StingsBee stings can leave a red bump, which is surrounded by white skin. 
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One of the best ways to know whether you can treat insect bites at home or seek immediate medical attention is to learn how to identify different bug bites. 

Identifying Insect Bites and Stings

1. Mosquito Bites

Mosquito bites are often itchy and leave reddish or pinkish bumps on the skin. Although a usual mosquito bite is unlikely to cause harm, there are mosquito bites that can also cause serious illnesses sometimes. They include:

  • Zika: The Zika virus is particularly dangerous to pregnant women. Newborns from pregnant women who are infected with this virus tend to develop a specific birth defect called microcephaly, in which the head is smaller than normally expected. Since they have a smaller head, they also have smaller brains. The disease caused by the Zika virus causes flu-like symptoms in some people. Zika virus is active in 50 areas, which include the Caribbean and Latin America. 
  • West Nile Infection: It is caused by a mosquito-transmitted virus called the West Nile virus. The symptoms usually appear within 2-14 days after the mosquito bite. Symptoms include a skin rash, fever, body aches, headaches, vomiting, and diarrhea. Those who develop a severe infection are more likely to develop encephalitis or meningitis. Symptoms of a severe West Nile infection include high fever, seizures or convulsions, severe headaches, a stiff neck, and disorientation. 
  • MalariaThis disease is transmitted by mosquitoes that carry a parasite called Plasmodium. Malaria rarely occurs in the United States with approximately 1,500 cases reported annually. Its symptoms are often the same as the flu, which includes headaches, fever, nausea, vomiting, and muscle pain. These symptoms occur 10 days to a month after the mosquito bite. Malaria is a serious and life-threatening condition. However, according to the Centers for Disease Control and Prevention (CDC), the disease is treatable and preventable. 

2. Bed Bug Bites

Bed bug bites are usually seen around a person's neck, back, hands, and legs. Their bites also depend on a person's sleeping position and the parts of the body being exposed. Most of the time, bed bug bites only cause mild reactions and symptoms. However, some people may also develop an allergic reaction to their bites. 

Their bites are also regarded as ghost bites since most people are unaware of their bites not until the bitten areas show raised, itchy, and red bumps. The bites may also develop into a rash if they are frequently scratched. The lesions often clear up after 1-2 weeks. 

3. Horse and Deer Fly Bites

For both animals and humans, horse flies are a common outdoor annoyance, especially during hot summer days. Horse flies are large and their bites are usually extremely painful since they cut the skin instead of piercing it. Upon cutting the skin, they inject saliva with an anticoagulant to help prevent the blood from clotting. It is the reason why their bites take a longer time to heal.

Their bites can also cause certain allergic reactions, such as difficulty breathing, hives, and anaphylactic shock in rare and extreme cases. Horse flies are often attracted to the warmth and movements of their potential victim, including exhaled carbon dioxide. 

These insects also feed on different animals including dead ones, making them an easy source of the following blood-borne diseases:

  • Loa loa filariasis or eye worm
  • Equine infectious anemia (EIA) or swamp fever
  • Anthrax (common among warm-blooded animals such as sheep and cattle)
  • Tularemia or rabbit fever

4. Spider Bites

In most cases, spider bites only cause mild symptoms, such as pain at the site of the bite, swelling, and red skin. However, there are also spider bites that require immediate medical attention, especially when you develop an allergic reaction to the bite. The symptoms of an allergic reaction may include:

  • Swelling of the face
  • Difficulty breathing
  • Chest tightness
  • Swallowing difficulties

The CDC recommends being updated with your booster shots for tetanus since spider bites can get infected with tetanus. A tetanus booster shot is also recommended once in 10 years. 

Dangerous and poisonous spider bites are those from the brown recluse and black widow spiders. Their bites often cause serious reactions, including difficulty breathing, nausea and vomiting, abdominal pain, back pain, and muscle pain within 7-8 hours after the bite. Initially, the bite of the black widow may or may not be painful. Its bite usually leaves two puncture marks. Swelling and pain in the bitten area may develop after 30-40 minutes of the bite.  

If you suspect that a poisonous spider has bitten you, seek medical attention right away. 

5. Brown Recluse Spider Bites

Brown recluse spiders often live in unused and dark areas. These spiders are poisonous. When bitten by a brown recluse spider, a small sting may be felt followed by a sharp pain. However, other people may remain unaware of the spider's bite for several hours. After 5-8 hours, the spider bite may become more painful. Around the site of the bite, a purplish blue color develops, and resemble a bruise or blister. The bite also turns darker and crusty later on. 

Within a few hours, the symptoms of a brown recluse spider bite develop and they include:

  • Fever
  • Itching
  • Chills
  • Sweating
  • Nausea

According to the If you suspect that a poisonous spider has bitten you, seek medical attention right away. 

6. Flea Bites

Bites of fleas are quite itchy and cause swelling and a small red rash or hives. One characteristic feature of flea bites is a red dot in the middle. Flea bites are commonly seen on a person's elbows, waist, knees, and ankles. 

Flea bites may also cause parasitic and bacterial infections, such as:

  • Hymenolepiasis: Fleas can also serve as intermediate hosts of parasites. Hymenolepiasis is the most common intestinal infection caused by tapeworms. 
  • Murine typhus: Fleas can also transmit this disease, which is also called as flea-borne typhus and endemic typhus. This disease is caused by Rickettsia typhi or Rickettsia felis, which are bacteria that can be found in infected fleas and their excreta (feces).
  • Cat-Scratch Disease: Also called as cat scratch fever, is an infection caused by a bacterium called Bartonella henselae. People get the disease from cats that are infected with B. henselae bacteria. Cats get the infection from flea bites and flea droppings. When cats bite or scratch the fleas, they pick up infected fleas between their teeth and under their nails. The infection spreads when infected cats scratch or bite humans strong enough to break or cut their skin. 

7. Bee, Hornet, and Wasp Stings

Bee stings cause a sharp pain at first for several minutes before developing into a dull, aching feeling that can be experienced for the next few hours. Bee stings are considered as one of the most painful insect bites. 

A bee sting may also dangerously trigger anaphylaxis in people who have an insect sting allergy. Moreover, when bees sting, they release pheromones, which can attract other nearby bees to attack. 

Bee stings can cause swelling, itching, and a painful sore after the sting. If you develop hypersensitivity after being stung by a bee, it is important to seek immediate medical attention. Other common symptoms of anaphylaxis are:

8. Tick Bites

Tick bites can sometimes be dangerous because ticks may carry certain diseases, such as:

  • Rocky Mountain spotted fever (RMSF) - from dog ticks
  • Lyme disease - from deer ticks or black-legged ticks

Each year, approximately 30,000 Lyme disease cases are reported in the United States alone. A characteristic symptom of Lyme disease is a skin rash that resembles a ring or a bull’s-eye, which shows within a month after a tick bite. Other symptoms of Lyme disease are:

  • Fever
  • Joint and muscle pain
  • Fatigue
  • Headaches
  • Irregular or an abnormal heart rhythm

However, around 20-30 percent of people who get infected with Lyme disease do not develop its characteristic rash. When Lyme disease is in its advanced stage, its symptoms may include:

  • Painful and swollen joints
  • Loss of memory
  • Autoimmune responses that tend to imitate other types of diseases

Rocky Mountain spotted fever is a rare disease caused by a tick bite. This disease causes a skin rash, fever, muscle pain, and headaches. The rash appears as small red spots that are initially noticed on the wrists and ankles after running a fever for a few days. The rash later spreads to the rest of a person's body. However, there are also some people who never get the rash. 

9. Lice Bites

People with lice may notice small red spots on their scalp, neck, and shoulders. Since lice have tiny bites, their bites often do not cause pain. However, their bites can be quite itchy. Other people may develop a larger rash due to their bites. 

Frequent itching of the affected areas may lead to an infection. Its symptoms often include painful, red skin and swollen lymph nodes. Lice bites that are infected may ooze and crust. The infection can be treated by a doctor. 

10. Ant Bites

Ant bites often leave painful red bumps on the skin. Certain types of ants, such as fire ants, can cause severe allergic reactions. 

A fire ant bite can cause a sharp and burning pain. After being bitten, fluid-filled blisters or pustules may develop after a couple of days. These bumps also appear red and swollen and can be itchy. Do not break open the blisters to avoid developing an infection. Carpenter ants can also cause painful bites due to the formic acid they spray into the bite.