Mosquitoes Prefer Beer Drinkers: Insights from a Festival Study

A new study explores why some people attract more mosquito bites, finding mosquitoes drawn to beer drinkers, those who skip sunscreen, and bed-sharers in a cross-sectional cohort study at the Lowlands Festival

In a quirky blend of science and summer vibes, researchers turned a Dutch music festival into a pop-up lab to uncover why some people are mosquito magnets while others escape unbitten. The study, detailed in a preprint published on bioRxiv on August 26, 2025, reveals that mosquitoes seem to favor the fun-loving crowd: those who enjoy a beer, skip the sunscreen, and share a tent overnight.

Conducted at the Lowlands Festival in Biddinghuizen, Netherlands, from August 18-20, 2023, the "Mosquito Magnet Trial" involved 465 participants – mostly festivalgoers aged 18 and up. The setup was far from your typical sterile lab: four shipping containers welded together formed a makeshift research station amid the beats of Billie Eilish and Underworld. Participants filled out anonymous questionnaires on their hygiene, diet, substance use, and festival antics, then underwent a breath alcohol test and a non-biting mosquito attraction assay.

How They Tested Mosquito Appeal

The clever experimental design used transparent cages housing 20-35 female Anopheles stephensi mosquitoes – malaria carriers in the wild, but here safely contained. Participants blew into the cage to release CO2 (a key mosquito lure) and pressed their arm against a perforated panel, allowing scents to waft in without any actual bites. A camera below tracked mosquito landings on the arm side versus a sugar feeder on the opposite side. Skin swabs from select participants also analyzed microbiota differences.

This video-based tracking quantified "relative attractiveness" as arm landings divided by total landings, controlling for mosquito fatigue and environmental factors like the container's heat (which sometimes made the bugs sluggish).

Key Findings: Party Habits Draw the Buzz

The results? Mosquitoes showed clear preferences, with some factors boosting attraction by over 30%:

• Beer Lovers Beware: Those who had at least one beer in the past 12 hours were 1.35 times more attractive (95% CI: 1.12–1.63, adjusted p < 0.001). Wine drinkers saw a similar trend, but it didn't hold after corrections. Interestingly, actual blood alcohol levels didn't correlate directly – suggesting it's the beer's scent or metabolites that entice, not intoxication itself.

• Bed-Sharing Bonus (for Mosquitoes): Participants who "lured a fellow human into their tent" the night before were 1.34 times more appealing (95% CI: 1.14–1.58, adjusted p = 0.002). The researchers quip that attraction might be "contagious," though they speculate on shared scents or behaviors.

• Sunscreen as Repellent: Applying sunscreen to the forearms reduced attraction by about half (fold change 0.52, 95% CI: 0.38–0.70, adjusted p < 0.001), especially if done after a recent shower. The effect faded with time since showering, hinting that sunscreen might mask human odors temporarily.

• Cannabis and Other Substances: Weed smokers in the past 48 hours showed a slight uptick in appeal (fold change 1.18), but it wasn't statistically robust after adjustments. Other drugs like XTC, amphetamines, or cocaine showed no significant effects.

• Skin Microbiome Insights: Highly attractive folks had more Streptococcus bacteria on their skin (uncorrected p = 0.017), a genus linked to body odors. However, overall microbial diversity didn't differ between groups, and dominant bacteria like Corynebacterium (known for malodor) were abundant across the board – perhaps amplified by the festival's sweaty atmosphere.

  
  

No links were found to blood type, age, gender, diet (e.g., vegetarianism), or coffee consumption, debunking some common myths.

Implications: Beyond the Buzzkill

Lead author Felix J.H. Hol and colleagues from Radboud University Medical Center note that while the study was "loosely controlled" with a bias toward science-curious festivalgoers, it's the largest of its kind. The findings could inform mosquito-borne disease prevention in endemic areas, where bite frequency heightens risks like malaria or dengue.

But for everyday folks? If you're heading to a summer bash, slathering on sunscreen might double as bug repellent – at least initially. And that beer? It might make you more popular with the winged crowd. As the authors humorously conclude, mosquitoes "simply have a taste for the hedonists among us."

The preprint, titled "Blood, sweat, and beers: investigating mosquito biting preferences amidst noise and intoxication in a cross-sectional cohort study at a large music festival," is available on bioRxiv (DOI: 10.1101/2025.08.21.671470). It's yet to undergo peer review, so take these buzzy results with a grain of salt – or perhaps a sip of something stronger.