Why are Some People Mosquito Magnets?

Jonathan Day • July 4, 2023

A medical entomologist points to metabolism, body odor, and mindset

It’s rare to attend an outdoor party in warm weather without hearing people complain about mosquitoes. They swat away, sit in campfire smoke, cover up with blankets and eventually just give up and go indoors. On the other end of the spectrum, there are plenty of people who don’t seem bothered by mosquitoes in the slightest.

As a medical entomologist who’s worked with mosquitoes for more than 40 years, I’m often asked why some people seem to be mosquito magnets while others are oblivious to these blood-feeding pests buzzing all around them.

Most mosquito species, along with a host of other arthropods – including ticks, fleas, bedbugs, blackflies, horseflies and biting midges – require the protein in blood to develop a batch of eggs. Only the female mosquito feeds on blood. Males feed on plant nectar , which they convert to energy for flight.

Blood-feeding is an incredibly important part of the mosquito’s reproductive cycle. Because of this, a tremendous amount of evolutionary pressure has been placed on female mosquitoes to identify potential sources of blood , quickly and efficiently get a full blood meal, and then stealthily depart the unlucky victim. If you check some, or all, of the mosquito’s search boxes, then you may find that you are a mosquito magnet.

This video by Deep Look explains some of the ways mosquitoes feed on blood.

Sensing CO2 and scent signals

Depending on when during the day they are active, mosquitoes use sight, sound and olfactory cues to identify a potential source of blood. Most night-active species rely on olfactory or receptor cues. The most important chemical cue is the carbon dioxide that all vertebrates, including humans, release with each breath and through their skin.

Mosquitoes are very sensitive to CO2 and can sense a CO2 source that is many meters away. Receptor cells on the mosquito’s antennae and legs bind CO2 molecules and send an electrical signal to the brain. When more molecules hit their receptors, the higher the CO2 concentration and the closer they are to the host.

However, there are many nonliving carbon dioxide sources such as cars, boats, planes and trains. To separate living from nonliving sources of CO2, mosquitoes rely on the secondary olfactory cues that living animals produce. Metabolic processes like breathing and moving generate these scent cues , including lactic acid, ammonia and fatty acids that act as additional olfactory clues that help female mosquitoes zero in on their next blood meal.

So, carbon dioxide production is the first mark of a mosquito magnet. Because the production of CO2 and secondary attractants is linked to metabolic rate, the higher the metabolic rate, the more attractants are produced. Metabolic rate can be genetically determined, but it also increases as the result of physical activity.

The human mosquito magnets you can spot at summer parties may have a genetically high metabolic rate or may be more physically active than other attendees. They may also be undertaking other activities that increase their metabolic rate, such as the consumption of alcohol. Increased metabolic rate is why runners attract more mosquitoes during their cooldown stretching exercises. Pregnant women, perhaps due to their increased metabolic rate, attract a disproportionately large number of mosquitoes as well.

This video by Business Insider explains some of the factors that can make a mosquito magnet.

Natural body odors are also important cues used by mosquitoes to select a host. For example, some species of Anopheles mosquitoes are attracted to specific components of foot odor. These mosquitoes transmit human malaria and feed indoors in the middle of the night. By feeding on a sleeping person’s feet, the mosquitoes avoid the head, where most of the CO2 is produced, and reduce the chance of waking the victim.

Visual cues

Mosquitoes active during the day and at dawn and dusk also use visual signals to identify a host. Mosquitoes usually fly close to the ground. From this vantage point they view their potential hosts against the horizon. Dark colors stand out and light colors blend in, so the way a person is dressed will determine the number of mosquitoes they attract. Wearing lighter colors may not just help keep you cool, but will help you evade a mosquito’s notice.

Mosquitoes can visually detect motion, again by contrasting a silhouette against the horizon. This is why people who walk near a saltmarsh in the middle of the day after a large emergence of saltmarsh mosquitoes are inundated by mosquitoes that visually detect their presence.

Psychological factors

There is also a psychological component to mosquito activity. Some people simply do not notice the mosquitoes around them. A single mosquito flying around some people will elicit a strong response – you’ve probably seen someone go nuts trying to track down the droning sound of one mosquito in order to finish off the tiny bloodsucker.

Other individuals are not bothered and do not notice the mosquitoes that are attracted to them, even when the insects are feasting on their blood. Some mosquitoes specialize on feeding on parts of the body that are difficult to see and difficult to swat. For example, Aedes aegypti is a mosquito species that prefers to feed on humans, mostly around the ankles.

Whether or not you’re a mosquito magnet, their bites feel just as itchy!The Conversation

Jonathan Day , Emeritus Professor of Medical Entomology, University of Florida

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Common Sense for the Eastern Shore

By Friends of Megan Outten July 29, 2025
Megan Outten, a lifelong Wicomico County resident and former Salisbury City Councilwoman, officially announced her candidacy recently for Wicomico County Council, District 7. At 33, Outten brings the energy of a new generation combined with a proven record of public service and results-driven leadership. “I’m running because Wicomico deserves better,” Outten said. “Too often, our communities are expected to do more with less. We’re facing underfunded schools, limited economic opportunities, and years of neglected infrastructure. I believe Wicomico deserves leadership that listens, plans ahead, and delivers real, measurable results.” A Record of Action and A Vision for the Future On Salisbury’s City Council, Outten earned a reputation for her proactive, hands-on approach — working directly with residents to close infrastructure gaps, support first responders, and ensure everyday voices were heard. Now she’s bringing that same focus to the County Council, with priorities centered on affordability, public safety, and stronger, more resilient communities. Key Priorities for District 7: Fully fund public schools so every child has the opportunity to succeed. Fix aging infrastructure and county services through proactive investment. Keep Wicomico affordable with smarter planning and pathways to homeownership. Support first responders and safer neighborhoods through better tools, training, and prevention. Expand resources for seniors, youth, and underserved communities. Outten’s platform is rooted in real data and shaped by direct community engagement. With Wicomico now the fastest-growing school system on Maryland’s Eastern Shore — and 85% of students relying on extra resources — she points to the county’s lagging investment as a key area for action. “Strong schools lead to strong jobs, thriving industries, and healthier communities,” Outten said. “Our schools and infrastructure are at a tipping point. We need leadership that stops reacting after things break — and starts investing before they do.” A Commitment to Home and Service Born and raised in Wicomico, Megan Outten sees this campaign as a continuation of her lifelong service to her community. Her vision reflects what she’s hearing from neighbors across the county: a demand for fairness, opportunity, and accountability in local government. “Wicomico is my home; it’s where I grew up, built my life, and where I want to raise my family,” Outten said. “Our county is full of potential. We just need leaders who will listen, work hard, and get things done. That’s what I’ve always done, and that’s exactly what I’ll continue to do on the County Council.” Outten will be meeting with residents across District 7 in the months ahead and unveiling more details of her platform. For more information or to get involved, contact info@meganoutten.com
By John Christie July 29, 2025
Way back in 1935, the Supreme Court determined that independent agencies like the Consumer Product Safety Commission (CPSC), the National Labor Relations Board (NLRB) and the Merit Systems Protection Board (MSPB) do not violate the Constitution’s separation of powers. Humphrey’s Executor v. United States (1935). Congress provided that the CPSC, like the NLRB and MSPB, would operate as an independent agency — a multi-member, bipartisan commission whose members serve staggered terms and could be removed only “for neglect of duty or malfeasance in office but for no other cause.” Rejecting a claim that the removal restriction interferes with the “executive power,” the Humphrey’s Court held that Congress has the authority to “forbid their [members’] removal except for cause” when creating such “quasi-legislative or quasi-judicial” bodies. As a result, these agencies have operated as independent agencies for many decades under many different presidencies. Shortly after assuming office in his second term, Donald Trump began to fire, without cause, the Democratic members of several of these agencies. The lower courts determined to reinstate the discharged members pending the ultimate outcome of the litigation, relying on Humphrey’s , resulting in yet another emergency appeal to the Supreme Court by the administration. In the first such case, a majority of the Court allowed President Trump to discharge the Democratic members of the NLRB and the MSPB while the litigation over the legality of the discharges continued. Trump v. Wilcox (May 22, 2025). The majority claimed that they do not now decide whether Humphrey’s should be overruled because “that question is better left for resolution after full briefing and argument.” However, hinting that these agency members have “considerable” executive power and suggesting that “the Government” faces greater “risk of harm” from an order allowing a removed officer to continue exercising the executive power than a wrongfully removed officer faces from being unable to perform her statutory duty,” the majority gave the President the green light to proceed. Justice Kagan, joined by Justices Sotomayor and Jackson, dissented, asserting that Humphrey’s remains good law until overturned and forecloses both the President’s firings and the Court’s decision to award emergency relief.” Our emergency docket, while fit for some things, should not be used to “overrule or revise existing law.” Moreover, the dissenters contend that the majority’s effort to explain their decision “hardly rises to the occasion.” Maybe by saying that the Commissioners exercise “considerable” executive power, the majority is suggesting that Humphrey’s is no longer good law but if that is what the majority means, then it has foretold a “massive change” in the law and done so on the emergency docket, “with little time, scant briefing, and no argument.” And, the “greater risk of harm” in fact is that Congress provided for these discharged members to serve their full terms, protected from a President’s desire to substitute his political allies. More recently, in the latest shadow docket ruling in the administration’s favor, the same majority of the Court again permitted President Trump to fire, without cause, the Democratic members of another independent agency, this time the Consumer Product Safety Commission (CPSC). Trump v. Boyle (July 23, 2025). The same three justices dissented, once more objecting to the use of the Court’s emergency docket to destroy the independence of an independent agency as established by Congress. The CPSC, like the NLRB and MSPB, was designed to operate as “a classic independent agency.” In Congress’s view, that structure would better enable the CPSC to achieve its mission — ensuring the safety of consumer products, from toys to appliances — than would a single-party agency under the full control of a single President. “By allowing the President to remove Commissioners for no reason other than their party affiliation, the majority has negated Congress’s choice of agency bipartisanship and independence.” The dissenters also assert that the majority’s sole professed basis for the more recent order in Boyle was its prior order in Wilcox . But in their opinion, Wilcox itself was minimally explained. So, the dissenters claim, the majority rejects the design of Congress for a whole class of agencies by “layering nothing on nothing.” “Next time, though, the majority will have two (if still under-reasoned) orders to cite. Truly, this is ‘turtles all the way down.’” Rapanos v. United States (2006). * ***** *In Rapanos , in a footnote to his plurality opinion, former Supreme Court Justice Scalia explained that this allusion is to a classic story told in different forms and attributed to various authors. His favorite version: An Eastern guru affirms that the earth is supported on the back of a tiger. When asked what supports the tiger, he says it stands upon an elephant; and when asked what supports the elephant, he says it is a giant turtle. When asked, finally, what supports the giant turtle, he is briefly taken aback, but quickly replies "Ah, after that it is turtles all the way down." John Christie was for many years a senior partner in a large Washington, D.C. law firm. He specialized in anti-trust litigation and developed a keen interest in the U.S. Supreme Court about which he lectures and writes.
By Shore Progress, Progessive Maryland, Progressive Harford Co July 15, 2025
Marylanders will not forget this vote.
Protest against Trumpcare, 2017
By Jan Plotczyk July 9, 2025
More than 30,000 of our neighbors in Maryland’s first congressional district will lose their health insurance through the Affordable Care Act and Medicaid because of provisions in the GOP’s heartless tax cut and spending bill passed last week.
Farm in Dorchester Co.
By Michael Chameides, Barn Raiser May 21, 2025
Right now, Congress is working on a fast-track bill that would make historic cuts to basic needs programs in order to finance another round of tax breaks for the wealthy and big corporations.
By Catlin Nchako, Center on Budget and Policy Priorities May 21, 2025
The House Agriculture Committee recently voted, along party lines, to advance legislation that would cut as much as $300 million from the Supplemental Nutrition Assistance Program. SNAP is the nation’s most important anti-hunger program, helping more than 41 million people in the U.S. pay for food. With potential cuts this large, it helps to know who benefits from this program in Maryland, and who would lose this assistance. The Center on Budget and Policy Priorities compiled data on SNAP beneficiaries by congressional district, cited below, and produced the Maryland state datasheet , shown below. In Maryland, in 2023-24, 1 in 9 people lived in a household with SNAP benefits. In Maryland’s First Congressional District, in 2023-24: Almost 34,000 households used SNAP benefits. Of those households, 43% had at least one senior (over age 60). 29% of SNAP recipients were people of color. 15% were Black, non-Hispanic, higher than 11.8% nationally. 6% were Hispanic (19.4% nationally). There were 24,700 total veterans (ages 18-64). Of those, 2,200 lived in households that used SNAP benefits (9%). The CBPP SNAP datasheet for Maryland is below. See data from all the states and download factsheets here.
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