The findings, published in iScience, could influence how scientists design mosquito repellents and disease-control strategies. The three species examined—Aedes aegypti, Aedes albopictus, and Culex quinquefasciatus—can transmit pathogens associated with yellow fever, dengue, Zika, West Nile fever and other illnesses. Although all mosquitoes use chemical signals to locate hosts, the study indicates that they do not interpret human odor in the same way. Their sensory systems appear to extract different information from the complex chemical environment surrounding the human body.

Human scent consists of more than 1,000 volatile organic compounds, or VOCs, many of which are released through the skin, breath and sweat. These molecules evaporate readily and form an odor cloud that mosquitoes can detect from a distance. The insects use specialized olfactory receptors, located mainly on their antennae and other sensory organs, to identify chemical cues associated with a potential blood meal. Carbon dioxide, body heat and moisture also help guide mosquitoes, but odor chemistry can determine which person an insect ultimately approaches.

In the FIU experiments, Aedes aegypti showed a preference for volunteers who were not wearing added fragrances and whose skin lacked certain volatile compounds. This species, a major vector of dengue, Zika, yellow fever and chikungunya viruses, is primarily active during the day. The researchers also observed a modest preference for men over women in the Aedes aegypti tests, although the study’s central result was the importance of individual chemical profiles rather than a simple demographic pattern.

The Asian tiger mosquito, Aedes albopictus, responded to a different chemical signature. It was attracted to elevated levels of ketones and plant-like volatile compounds naturally released by the skin. Ketones are organic molecules produced during normal metabolism and can vary with diet, physiology and other biological factors. Plant-associated VOCs may originate from human skin chemistry, environmental exposure or interactions between skin compounds and resident microorganisms. Like Aedes aegypti, Aedes albopictus feeds mainly during daylight hours and is capable of spreading several medically important viruses.

The southern house mosquito, Culex quinquefasciatus, displayed a distinct pattern. This nighttime-feeding species was strongly influenced by the skin microbiome—the community of bacteria, fungi and other microorganisms living on the surface of the body. Microbes metabolize compounds in sweat and skin secretions, producing secondary chemicals that contribute to a person’s characteristic odor. Some bacterial families appeared to make volunteers more attractive to Culex quinquefasciatus, while others were associated with reduced attraction. This finding connects microbial metabolism directly to the host-seeking behavior of a disease vector.

The researchers combined behavioral preference tests with chemical and microbiological sampling. Volunteers were evaluated according to how strongly mosquitoes responded to them, while odor samples were analyzed to identify volatile compounds and skin samples were examined for microbial composition. Comparing these datasets allowed the team to associate particular chemical molecules and bacterial groups with mosquito attraction or avoidance. The approach is important because it moves beyond the idea that humans are simply “more” or “less” attractive to mosquitoes and instead investigates which biological signals are recognized by each species.

According to Matthew DeGennaro, the FIU neurogeneticist who led the research, the results indicate that the skin microbiome helps define an individual’s human odor signature. Kaylee Marrero, the study’s lead author, said the team had not expected the mosquito species to prefer different people. The discovery that each species may use a distinct microbial or chemical signature suggests that mosquito sensory systems have evolved in different ecological directions, even when the insects feed on the same host.

The findings may eventually support species-specific repellents that interfere with the precise receptors or odor-processing pathways used by a target mosquito. A compound that masks an attractive chemical for Aedes aegypti may have little effect on Aedes albopictus or Culex quinquefasciatus. Tailoring repellents to the dominant mosquito species in a region could improve personal protection and public-health campaigns, particularly in areas where viral transmission changes seasonally or geographically. However, the researchers emphasize that human odor is only one component of mosquito behavior. Temperature, carbon dioxide, movement, clothing, habitat and time of day also influence host selection. The new study provides a chemical framework for understanding why mosquito bites are unevenly distributed among people—and why the answer may depend on which mosquito is doing the biting.

Subject of Research: Not applicable

Article Title: Individual humans are more attractive to certain mosquito species

News Publication Date: 21-Aug-2026

Web References: https://www.sciencedirect.com/science/article/pii/S2589004226023849?via%3Dihub

References: https://doi.org/10.1016/j.isci.2026.117006

Image Credits: Christopher Necuze/Florida International University

Keywords: mosquitoes, mosquito attraction, human odor, skin microbiome, volatile organic compounds, Aedes aegypti, Aedes albopictus, Culex quinquefasciatus, dengue, Zika, yellow fever, West Nile virus, mosquito repellents, vector-borne disease

Amid this global health crisis, the city of Niterói in Rio de Janeiro state, Brazil, emerged as an extraordinary example of innovation and hope. Unlike many regions struggling with soaring dengue incidences, Niterói demonstrated remarkable resilience through a groundbreaking biological intervention—the release of Aedes aegypti mosquitoes infected with the wMel strain of Wolbachia bacteria. This innovative strategy aimed to impair the mosquitoes’ capacity to transmit the dengue virus, fundamentally altering the disease dynamics in the city.

The scientific basis for this approach lies in the unique properties of the Wolbachia bacteria, a naturally occurring endosymbiont found in many insect species but not originally present in Aedes aegypti mosquitoes. When introduced into these mosquitoes, Wolbachia inhibits the replication of dengue virus within their bodies, thus preventing onward transmission to humans. Over the course of five years, systematic releases of wMel-infected mosquitoes resulted in the majority of the local mosquito population carrying the bacterium, effectively reducing the city’s dengue incidence by an extraordinary 89%.

Led by researchers from Monash University in Melbourne and the World Mosquito Program, the study assessing this intervention’s long-term efficacy was published in the journal Tropical Medicine and Infectious Diseases. The research team, including Associate Professor Katherine Anders and Professor Luciano Moreira, now CEO of Wolbito do Brasil, conducted extensive monitoring in Niterói, a city with a population roughly half a million. Their findings underscored the profound public health impact during the record-breaking dengue epidemic in Brazil in 2024.

In that year, Niterói reported a dengue incidence of just 374 cases per 100,000 population—a remarkable figure when compared to 1,884 per 100,000 in Rio de Janeiro state overall, and an even more staggering 3,157 per 100,000 across the entire country. This stark contrast evidences the intervention’s effectiveness, proving that the widespread establishment of Wolbachia within vector populations not only curtails disease transmission but also offers a scalable and sustainable solution for dengue control.

Traditional methods of controlling dengue vectors, such as insecticide application and source reduction, have encountered significant hurdles over time. Insecticide resistance has become pervasive among Aedes aegypti populations, diminishing the success of chemical control strategies. Furthermore, urban environments present complex logistical challenges for mosquito control programs, complicating efforts to maintain consistent and widespread coverage. In contrast, Wolbachia deployment circumvents these problems through a self-sustaining biological mechanism, reducing reliance on repeated chemical interventions.

The innovative method pioneered in Niterói has garnered international attention, and in July 2024, Brazil unveiled the world’s largest biofactory dedicated to breeding Wolbachia-infected mosquitoes. Located in Curitiba and named Wolbito do Brasil, this facility aims to produce millions of infected mosquitoes to supply various regions across the country. Professor Moreira highlighted that this initiative is poised to protect an estimated 140 million people from dengue fever in Brazil in coming years, marking a significant step forward in the fight against vector-borne diseases.

From a technical standpoint, the success of the wMel strain of Wolbachia in suppressing dengue transmission is attributed to several key factors. The bacterium manipulates mosquito biology by inducing cytoplasmic incompatibility, ensuring that Wolbachia-infected females produce offspring carrying the bacteria, thereby facilitating its spread through mosquito populations. Additionally, Wolbachia triggers immune system pathways within the mosquito, further limiting viral replication. Together, these mechanisms reduce the vector competence of mosquitoes without significantly impairing their survival or reproduction.

The ecological and epidemiological implications of this intervention are profound. Establishing a stable Wolbachia presence in mosquito populations can lead to a durable reduction in dengue transmission potential, decreasing outbreaks and associated morbidity and mortality over the long term. This achievement supports the hypothesis that biologically based vector control strategies can complement or even replace conventional approaches, particularly in densely populated urban centers where rapid dengue spread is common.

Despite the compelling results in Niterói, scientists emphasize the importance of continued surveillance, community engagement, and iterative optimization of Wolbachia deployment strategies. Factors such as local environmental conditions, mosquito population dynamics, and human movement patterns can influence intervention efficacy. As such, integrating these variables into ongoing monitoring will be critical for maximizing the public health benefits of Wolbachia programs as they scale to other regions facing dengue and related arboviruses.

Moreover, the success of this program resonates beyond dengue fever, offering a transferable model for controlling other mosquito-borne diseases such as Zika, chikungunya, and yellow fever. Wolbachia’s ability to inhibit multiple pathogens within the same vector underscores its potential as a versatile tool in integrated vector management frameworks. This multifunctionality equips public health authorities with a powerful strategy to confront an array of emerging threats exacerbated by climate change and urbanization.

In light of these transformative findings, the global health community is increasingly recognizing Wolbachia deployment as a paradigm shift in vector control. The compelling data from Niterói’s experience highlights the intersection of cutting-edge microbiology, vector ecology, and public health intervention science. By reducing dengue incidence nearly tenfold during a historic epidemic surge, the Wolbachia program exemplifies innovation unlocking new possibilities for disease prevention on a planetary scale.

As efforts to expand Wolbachia mosquito releases progress worldwide, ongoing collaborations between academic institutions, governmental agencies, non-governmental organizations, and affected communities will play a pivotal role in shaping the future of arboviral disease control. Harnessing this symbiotic bacterium’s power represents a lasting legacy for public health, forging a path toward safer, healthier, and more resilient tropical populations vulnerable to dengue and beyond.

Subject of Research: People

Article Title: Long-Term Durability and Public Health Impact of City-Wide wMel Wolbachia Mosquito Releases in Niterói, Brazil, During a Dengue Epidemic Surge

News Publication Date: 25-Aug-2025

Web References:
DOI: 10.3390/tropicalmed10090237

Keywords: Human health, Diseases and disorders

At the heart of this research lies the use of universal DNA-based molecular tools, enabling the precise identification of host species from blood-meal samples collected around the world. This innovation transcends previous methodologies limited by narrower detection scopes, thereby illuminating feeding patterns across an astonishing variety of host animals. By aggregating more than 15,600 blood-meal records pertaining to six of the planet’s most epidemiologically significant mosquito species, the international team was able to map a complex feeding landscape that varies not only by mosquito genus but also by geographical and environmental contexts.

Dr. Konstans Wells, lead investigator from Swansea University, emphasized the remarkable plasticity observed in mosquito host selection. While it has long been recognized that female mosquitoes inherently favor certain host species for blood feeding, Wells’ team demonstrated substantial regional variability shaped by ecological parameters. Factors such as ambient temperature fluctuations and local livestock densities emerged as influential drivers that modulate mosquito feeding choices. This insight considerably deepens the complexity surrounding disease ecology modeling, given that host preference is a key determinant in pathogen transmission dynamics.

One of the most striking revelations from the analysis is the expansive host range of Culex mosquitoes, which exhibit feeding upon between 179 and 321 distinct vertebrate species. This vast dietary breadth starkly contrasts with that of Aedes mosquitoes, which feed across 26 to 65 species, and Anopheles mosquitoes whose host ranges are narrower still, spanning between 7 and 29 species. These findings not only illuminate fundamental ecological behaviors but are vital for understanding the transmission potential of diseases such as West Nile virus, dengue fever, and malaria, each of which is vectored predominantly by different mosquito taxa.

The impetus for this comprehensive meta-analysis originated, in part, from preliminary work conducted under the guidance of Dr. Wells by then-undergraduate student Meshach Lee. Lee’s initial dissertation project revealed significant regional disparities in mosquito feeding dynamics concerning human, wildlife, and livestock hosts. The thorough meta-analytical approach employed in the new study validated these observations and extended them by incorporating robust molecular evidence. Lee reflected that this refined methodology delivers a more nuanced and accurate depiction of mosquito feeding ecology than previously feasible with conventional approaches.

Despite the expansive dataset and innovative analytical techniques, researchers acknowledge persistent challenges in forecasting mosquito feeding behavior with precision. Variability induced by local environmental heterogeneity and complex host-vector-pathogen interactions renders prediction a formidable task. Dr. Wells advocates for enhanced standardization in blood-meal study protocols, emphasizing that consistent application of molecular methods and systematic collection of detailed environmental data are essential to improve predictive reliability regarding mosquito feeding patterns and consequent disease risk.

Further contributions to the research were made by colleagues Dr. Tamsyn Uren Webster of Swansea University, Dr. Richard O’Rorke from the University of Auckland, and Dr. Nicholas Clark of the University of Queensland. Their collaborative efforts underpin a study that marks the first major application of universal DNA diet analysis to mosquito feeding behavior on a global scale. This represents a significant milestone in vector ecology, elucidating the intricate and dynamic interactions between mosquitoes and their hosts, especially under the accelerating pressures of climate change.

These insights hold substantial implications for global public health strategies aimed at mitigating vector-borne diseases. The demonstrated feeding flexibility demands a reevaluation of surveillance and control measures, which have historically been predicated on more static assumptions of mosquito-host relationships. Enhanced molecular surveillance can empower targeted interventions attuned to local ecological contexts, potentially improving the effectiveness of disease control programs in regions afflicted by malaria, dengue, Zika virus, and other mosquito-borne illnesses.

The study also highlights the necessity of integrating ecological complexity into models predicting disease emergence and spread. As climate change modifies habitats, wildlife distributions, and human-livestock interactions, mosquito feeding patterns are likely to shift unpredictably. Understanding these dynamics at a molecular and ecological level offers the potential to anticipate emerging health threats and adapt mitigation strategies accordingly.

Moreover, the research underscores the importance of bridging ecological science and public health policy. By providing a granular understanding of mosquito feeding ecology through universally applicable DNA methods, this work enables health authorities worldwide to make informed decisions grounded in rigorous scientific evidence. This multidisciplinary approach aligns with international goals such as the United Nations Sustainable Development Goal 3, which aims to ensure healthy lives and promote well-being for all ages, partly by reducing the burden of infectious diseases.

In sum, this pioneering meta-analysis presents a transformative vision of mosquito feeding ecology. It reveals that mosquito feeding behavior is not a fixed trait but a dynamic, environmentally influenced spectrum that challenges previous dogma and calls for more nuanced, adaptable disease management strategies. By harnessing the power of universal molecular identification techniques, the study circumvents previous methodological barriers and opens new frontiers in understanding the ecology of vectors that affect millions worldwide.

With mosquito-borne diseases representing a persistent and evolving threat, the growing knowledge generated via this research represents a vital tool in combating the public health challenges posed by these tiny but deadly vectors. As researchers and policymakers endeavor to outpace the spread of mosquito-borne pathogens, the revelations about host diversity and feeding plasticity detailed here provide a critical foundation for more resilient, informed, and effective intervention measures.

Subject of Research: Animals

Article Title: Diversity and Plasticity in Mosquito Feeding Patterns: A Meta-Analysis of ‘Universal’ DNA Diet Studies

News Publication Date: 19-Jun-2025

Web References:

• DOI: 10.1111/geb.70077
• UN Sustainable Development Goal for good health and well-being

References: See the linked DOI for the full research article.

Keywords: Mosquito feeding behavior, host diversity, molecular ecology, vector-borne diseases, climate change, meta-analysis, Culex, Aedes, Anopheles, disease transmission, DNA diet studies, vector surveillance.