Why mosquitoes bite you more than everyone else

If you are the person in the garden who collects every bite while the rest of the table is untouched, you are not imagining it. Mosquito attraction is measurable and unevenly distributed, and roughly a fifth of people are strongly preferred by the insects around them. Understanding why matters, because most of the popular fixes target the wrong signal entirely.

Carbon dioxide is the long-range beacon

A female mosquito hunting for a blood meal picks up carbon dioxide plumes from tens of metres away. That is the first cue, and it is the reason larger adults, pregnant women and anyone who has been exercising are bitten more. You exhale more, you broadcast further. This is also why sitting still with a cold drink does not save you: you are still the loudest source of CO2 at the table.

Because CO2 is the long-range signal, anything that promises to hide you from mosquitoes has to compete with your own breathing. It rarely does. The more reliable strategy is to give the insects a stronger, more attractive target somewhere else in the garden — which is exactly the logic a UV light trap runs on.

Skin chemistry decides who gets picked at close range

Once a mosquito is within a couple of metres, the decision is made on skin volatiles: lactic acid, ammonia, uric acid and the specific mix of bacteria living on your skin. Studies repeatedly find that the composition of skin microbiota predicts attractiveness better than almost anything else. People with a less diverse but more abundant skin flora tend to be bitten more.

This is largely genetic and not something you can shower away, though washing does reduce the load temporarily. Feet are a particular hotspot; the bacteria that make socks smell are the same ones that make ankles the single most bitten body part in the average garden.

Blood type, beer and dark clothing

Type O blood shows up in several studies as more attractive than type A, with type B in between. The effect is real but smaller than CO2 and skin chemistry. Drinking a beer has been shown in small studies to increase landing rates, probably through a combination of skin temperature and subtle changes in volatile output. Dark clothing helps mosquitoes find you visually at close range, especially at dusk.

What actually reduces bites in a garden

The interventions that work, in rough order of effect: eliminate standing water within about 100 metres so the local population never hatches; cover skin at dusk and dawn when most species feed; use a DEET or picaridin repellent on exposed skin if you are willing to; and place an attractant-based trap or UV zapper away from where you sit, so the insects that do arrive are pulled past you rather than to you.

The interventions that do not work well: citronella candles, which produce a plume too small and too easily blown away; ultrasonic repellers, which have failed every controlled test they have been put through; and wristbands, which protect a wrist.

Placement is the part everyone gets wrong

If you take one practical thing from this article, make it placement. A light-based trap works by being more interesting than you are. Put it on the table beside you and you have simply invited mosquitoes to your seat. Put it five to eight metres away, slightly upwind, at roughly head height, and it does what it is supposed to do. Cordless units make this easy because they are not tied to a socket; mains units often end up in the wrong place purely because that is where the cable reached.

The realistic expectation

No single device makes a garden bite-free. What a good setup does is take an evening from unbearable to comfortable — from five or six bites to zero or one. That is the honest benchmark to hold any product to, and it is the benchmark we use in our testing.