Study at Dutch festival finds beer drinkers more attractive to mosquitoes
Researchers say alcohol consumption, recent sexual activity and lack of sunscreen were linked to higher mosquito attraction in a 500-person field study
A field study of festivalgoers in the Netherlands found people who drank beer were more attractive to female mosquitoes than those who did not, with researchers reporting a 1.35-fold increase in attraction among beer drinkers.
The team from Radboud University recruited about 500 participants at a music festival and exposed them to thousands of Culex mosquitoes in a controlled setup. Participants completed questionnaires about hygiene, diet and behaviour before placing an arm into a custom-designed cage with tiny holes that allowed the insects to smell the skin while preventing biting; a video camera recorded how many mosquitoes attempted to land or probe.
In addition to beer consumption, the study found higher mosquito attraction among participants who said they had slept with someone the previous night. Wearing sunscreen and recent showering were associated with lower attraction. The researchers said their results suggest individual body odours, which can be influenced by factors such as blood alcohol concentration, play an important role in which people mosquitoes choose to target.
The paper was uploaded to the bioRxiv preprint server and has not yet completed peer review. The authors noted that common popular explanations—including the idea of "sweet blood"—could not be assessed in this study. They said they found no evidence that blood type reliably predicted bite frequency in their sample.
Researchers described the attraction process as a two-stage search in which mosquitoes first detect carbon dioxide exhaled by humans and then home in on individual odour cues that determine bite choice and frequency. The festival-based setting allowed the team to observe variation across a large, real-world population under similar environmental conditions, the authors said.
Mosquitoes are not only a source of nuisance bites but also a global public-health concern because some species transmit pathogens such as malaria and dengue fever. Climate change and warming temperatures have raised concerns among entomologists and public-health experts that species currently limited to tropical and subtropical regions, including the Asian tiger mosquito, could establish in parts of Western Europe and increase the risk of local transmission of mosquito-borne illnesses.
Previous research has identified several factors that can affect mosquito attraction, including body temperature, exercise-related lactic acid, skin bacteria composition and body odour. Some studies have reported variation by human blood type, while others point to the microbial communities on skin as an important determinant of how attractive a person is to mosquitoes.
The authors cautioned against overgeneralizing from a single festival sample and noted limits of their measures. The experimental design prevented actual bites, allowing the researchers to quantify mosquito interest without confounding by defensive swatting or other behaviours that influence real-world bite outcomes. They called for further controlled and longitudinal studies to clarify how short-term behaviours such as alcohol consumption and hygiene interact with more stable individual factors to shape mosquito-host interactions.
For people concerned about bites during outdoor events, the study reinforces established prevention measures such as using insect repellent, applying sunscreen and maintaining personal hygiene. Public-health officials continue to monitor mosquito populations and climate trends that could alter the risk of mosquito-borne disease in temperate regions.