Can you get sick from too many noseeum bites? Understanding the health risks

September 30, 2025 •

4 min read

According to the University of Florida's Institute of Food and Agricultural Sciences, a single no-see-um bite can result in an intensely itchy welt lasting up to two weeks. But when you have been bitten many times, the question becomes: can you get sick from too many noseeum bites? While systemic illness is rare, excessive bites can lead to other complications that warrant medical attention.

Quick Summary

Excessive noseeum bites pose health risks like severe allergic reactions or secondary skin infections caused by scratching. Certain midge species in specific regions transmit diseases, though this is rare in the United States and Canada.

Key Points

Allergic Reactions are Common: While not a systemic illness, intense or excessive no-see-um bites can cause severe localized allergic reactions, including exaggerated swelling and blistering.
Infection Risk is the Main Threat: The primary health risk from excessive bites is secondary bacterial infection, such as cellulitis, caused by scratching the itchy welts.
Disease Transmission is Geographically Limited: The transmission of viruses like Oropouche or bacteria like Bartonella by midges is rare and confined to specific tropical regions, not a typical threat in most of the U.S. or Canada.
Recognize Severe Symptoms: If you experience extreme swelling, pus, fever, or flu-like symptoms after multiple bites, seek medical attention, as it may indicate an infection or rare severe reaction.
Prevention is Key: The most effective way to avoid getting sick is to prevent bites altogether by using repellents, wearing protective clothing, and installing fine-mesh screens.

The Primary Health Threats: Allergic Reactions and Infections

For most people in North America, the main health concerns from excessive no-see-um bites are localized reactions and infections. While you may not catch a virus, an onslaught of these tiny, painful bites can still make you quite ill, especially if your immune system is overtaxed by the inflammatory response.

Allergic Reactions to Excessive Bites

When a no-see-um bites, it injects saliva containing proteins into your skin. This triggers an immune response that causes itching and swelling. The severity of this reaction can vary widely from person to person. For individuals who are hypersensitive, repeated or excessive bites can cause a more significant allergic response, a condition similar to Skeeter Syndrome seen with mosquito bites.

Symptoms of a severe localized reaction can include:

Exaggerated swelling and redness that extends far beyond the bite site.
Blistering around the bites, especially with repeated scratching.
Systemic symptoms such as fever, fatigue, and swollen lymph nodes in rare, extreme cases.

The Danger of Secondary Infections

The intense itching from no-see-um bites often leads to scratching, which is one of the most common ways to develop a secondary infection. When you break the skin by scratching, you introduce bacteria from your hands and fingernails. This can result in bacterial skin infections like impetigo or cellulitis, which require antibiotics to treat.

To avoid infection:

Resist the urge to scratch the bites.
Keep the affected areas clean with soap and water.
Use over-the-counter anti-itch creams to relieve discomfort.

Understanding Rare Systemic Illnesses from Biting Midges

While the risk is extremely low in the United States and Canada, specific species of biting midges (the family that no-see-ums belong to) can transmit diseases in other parts of the world. The risk is generally associated with tropical regions, so travelers should be aware if they visit these areas.

Oropouche Virus (OROV)

The Oropouche virus is one of the most significant midge-borne illnesses, transmitted by the bite of an infected midge (Culicoides paraensis) or certain mosquitoes. While it primarily circulates in parts of South America, Central America, and the Caribbean, some midge species in the US Southeast and Midwest could potentially transmit it. OROV typically causes a sudden onset of symptoms that can mimic dengue, Zika, or chikungunya.

Symptoms include:

High fever
Severe headache
Chills and muscle aches
Joint pain
In rare cases, more serious complications like meningitis (inflammation of the brain and spinal cord) or encephalitis.

Carrion's Disease (Bartonellosis)

This disease, caused by the bacterium Bartonella bacilliformis, is transmitted by a type of sand fly found in specific high-altitude regions of South America. If untreated, it can lead to a fatal form of hemolytic fever. Though limited to certain geographical areas, this illustrates the potential for severe, midge-borne illness.

Other Risks like Mansonellosis

Another parasite, Mansonella, can be transmitted by biting midges in South America and the West Indies. Infections are often asymptomatic but can cause non-specific symptoms such as itching, enlarged lymph glands, and joint pain.

Comparing Bite Reactions and Systemic Illness


Feature	Common Localized Reaction	Severe Allergic Reaction	Systemic Illness (e.g., OROV)
Cause	Your immune system reacting to midge saliva.	Hypersensitivity or extreme exposure to bites.	Midge or mosquito transmitting a specific pathogen.
Symptoms	Itchy, red welts or bumps that can last days to weeks.	Extreme swelling, redness, blisters; possibly fever and fatigue.	High fever, severe headache, muscle/joint pain, chills; can lead to meningitis.
Duration	Few days to two weeks.	Can last longer, depending on severity and treatment.	Typically weeks to a month; depends on pathogen.
Location	Anywhere no-see-ums are present.	Anywhere no-see-ums are present.	Confined to specific tropical regions where the pathogen exists.
Treatment	At-home care: wash, cool compress, hydrocortisone/antihistamine.	Medical consultation, prescription steroids, potentially emergency care.	Medical treatment, typically supportive care, sometimes antibiotics for coinfections.

Conclusion: Minimizing Your Risk

While the average person is unlikely to get systemically sick from a few no-see-um bites, the risk increases with extreme exposure or for travelers in endemic areas. The main dangers stem from secondary infections and intense allergic reactions, both of which can be prevented with simple precautions. Staying vigilant and taking preventive measures, like using effective repellents and fine-mesh screens, is the best way to avoid discomfort and potential health complications from these minute but mighty pests. In case of severe reactions or signs of infection, consulting a healthcare professional is crucial. For general prevention advice from an authority on this topic, see this publication from the University of Florida's Institute of Food and Agricultural Sciences: Biting Midges, No-See-Ums.

Frequently Asked Questions

Excessive no-see-um bites typically result in a cluster of small, red, intensely itchy welts, often more painful than a mosquito bite. They can also cause localized swelling and redness that may last for up to two weeks.

Yes, scratching the bites can break the skin, allowing bacteria to enter and cause secondary infections such as impetigo or cellulitis. This is a primary health risk associated with excessive scratching.

Disease transmission from midges (no-see-ums) is rare in the United States. However, in tropical regions of South and Central America, and the Caribbean, some midge species can transmit pathogens like the Oropouche virus.

A severe allergic reaction can cause exaggerated swelling, redness, and blistering around the bite area. In rare cases, systemic symptoms like fever and swollen lymph nodes may occur.

Oropouche virus is a disease spread by biting midges in certain tropical areas, causing symptoms like fever, severe headache, and joint pain. Travelers visiting endemic regions should take extra precautions to prevent bites.

If your bites show signs of infection, such as increased pain, swelling, warmth, pus, or fever, you should see a doctor. A medical professional will likely prescribe antibiotics to clear the bacterial infection.

Preventative measures include using insect repellent containing DEET or picaridin, wearing light-colored, protective clothing, using fine-mesh window screens, and avoiding outdoor activity during dawn and dusk.