Bites from bed bugs and mosquitoes are both red and itchy and may seem similar. However, they come from separate creatures and have a few different characteristics.

Bed bug bites usually occur in a cluster or pattern, such as a line or a zigzag. Mosquito bites are usually isolated and do not follow a pattern.

Being able to tell the difference between the two means people can respond appropriately to the bites they get and take steps to keep from getting more.

This article discusses the differences between and treatments for bed bug bites and mosquito bites.

Like other bites, individuals react differently to bed bug bites, and it can take hours or days for these reactions to show up.

Some people find bed bug bites itchy and irritating, while others will develop more swollen, painful reactions.

Severe allergic responses are rare but can include anaphylaxis, which starts with a feeling of the throat closing up. Anaphylaxis can be life threatening and affect the whole body.

Individuals usually get several bed bug bites at a time, often in groups of three to five. The bites themselves are red and itchy and sometimes have a blister on top.

Bed bugs live on blood and are primarily active at night, so bites tend to show up where the skin is exposed at night.

Bed bugs must eat at least every 14 days to mate and produce eggs, but they can survive for up to a year without eating.

Learn more about bed bug bites.

Female mosquitoes are the only mosquitoes that bite. The contact must last at least 6 seconds for enough mosquito saliva to enter the bloodstream and cause a reaction.

Mosquito bites resemble red bumps with a puncture wound in the center. If a person is very sensitive, they can produce welts or larger raised areas.

The bites itch because of how the immune system responds to mosquito saliva.

Mosquitoes are most likely to bite in the dark, between sunset and sunrise. Carbon dioxide, human sweat, and warmth may attract mosquitoes.

Learn more about mosquito bites.

Bites by mosquitoes and bed bugs have different characteristics on a person’s skin and in several other ways.

Appearance

Bed bug bites usually occur in a cluster and often in a distinct pattern, such as a line or a zigzag. Bites typically appear in exposed areas during sleep, such as the ankles.

Mosquito bites, on the other hand, are generally isolated and appear randomly over parts of the body that clothing does not cover.

Reaction time

People typically do not feel bed bug bites and reactions may present hours or days later. Without further irritation, symptoms usually resolve after a week or so.

Mosquito bites may be instantly itchy and visible. Typically, they get better after 1 or 2 days.

Infection

In addition to itching and irritation, mosquito bites can spread serious diseases.

Although they transmit many diseases, common mosquito-borne diseases include:

Unlike mosquitoes, public health experts do not believe bed bugs spread disease.

However, any bite can become infected if a person scratches it too much and does not keep their hands or the bite clean.

An infected bite may appear inflamed and feel warm and painful. It is best to contact a healthcare professional if someone suspects an infected bite.

The symptoms of bed bug bites and mosquito bites can be distinguishable, which may help people identify which type they have.

Bed bug bites

Symptoms of bed bugs include:

  • small, raised, red bumps in groups of three to five
  • bumps often appear in a zigzag pattern on the hands, arms, shoulders, neck, face, and legs
  • bumps are itchy and may come with a blister

Mosquito bites

The symptoms of mosquito bites for most people are itchy, red bumps with puncture wounds in the middle. They usually appear within a few hours or days after the bite.

People who are allergic to mosquito bites may also develop:

Most of the time, neither bed bug bites nor mosquito bites require medical treatment unless an individual has an exceptional allergic reaction or develops an infection.

Anaphylaxis is a rare response to these kinds of bug bites, but if someone feels that their throat is closing up, they must seek medical help immediately.

The basic steps in treating bed bug bites or mosquito bites include:

  • washing the bites with soap and water
  • trying not to scratch, as it may irritate or break the skin, causing additional problems
  • keeping the affected area clean and dry
  • using antiseptic lotions and anti-itch creams to protect the skin and relieve itching
  • taking an over-the-counter (OTC) antihistamine if needed

There are some things that people can do to lessen the risk of acquiring insect bites.

Bed bug bites

To avoid bed bug bites when traveling, people may want to check beds thoroughly for signs of bed bugs on mattresses and around the headboard. They can also avoid putting suitcases on the floor.

To prevent bed bug bites at home:

  • check items brought into the home, including clothes someone has worn on trips and used furniture
  • use a bed bug-proof cover over mattresses
  • reduce clutter where possible, as bed bugs thrive in clutter

If a bed bug infestation develops, it is often necessary to hire a professional pest remover who specializes in bed bugs to get rid of them completely.

Mosquito bites

The following actions can help prevent mosquito bites:

  • Remove mosquito habitats by getting rid of standing water in pet dishes, buckets, toys, and other containers and changing water in a birdbath, for example, at least once a week.
  • Make sure bug screens for windows and doors have no holes.
  • Wear pants and long-sleeve shirts when venturing outside, especially in the woods, at dusk, and at other places and times mosquitoes like to feed.
  • Use insect repellent, especially when going outdoors.
  • Install yellow “bug” light bulbs where appropriate outside, which will not repel bugs but will attract fewer.

The cause of itchy, red bumps may not always be due to bed bugs and mosquitoes. Other potential culprits include:

  • Fleas: Flea bites can appear in clusters, similar to bed bug bites.
  • Flies: A fly bite can itch and blister on the skin.
  • Spiders: Spider bites can turn red and swell, and some spider bites can be dangerous.
  • Mites: Among the different mite types, scabies burrow into the skin, creating tunnels and causing inflammation and itching.

Learn more about insect and spider bites and how to deal with them.

Most of the time, people do not need to see a doctor for bed bugs or mosquito bites.

The two exceptions are if an individual has a serious allergic reaction to the bites or if they develop secondary infections as a result of the bites.

Signs that someone needs to see a doctor include:

  • feeling that the throat is closing up — seek help immediately
  • having a large number of bites
  • developing fever, swelling, hives, blisters, or pus
  • getting no relief from OTC anti-itch medications

Bites from bed bugs and mosquitoes are very common. They can cause significant discomfort and irritation but rarely need medical attention and usually clear up in a few days.

Taking steps to avoid future exposure to both bed bugs and mosquitoes and working hard to remove bed bugs can limit future bites.