As members of the E4Warning consortium, Gina Tsarouchi, Quillon Harpham (HR Wallingford), Lyra Tyson (UPF), and Remy Hoek Spaans (BSC) traveled to Sri Lanka in November to participate in a workshop organized by Dr. Lahiru Kodithuwakku and Gina Tsarouchi. The event, in collaboration with the National Dengue Control Unit (NDCU) and the Ministry of Health, focused on enhancing innovative tools for dengue prediction and control.

The workshop aimed to train participants in using the D-MOSS platform, a live dengue forecasting system combining satellite earth observation data, climate models, and statistical tools to provide probabilistic forecasts of dengue outbreaks. It also served as a valuable opportunity to adapt the methods to Sri Lanka’s unique public health context, informed by input from local professionals.

Bringing Together Experts from Across Sri Lanka

The workshop attracted over 80 participants from districts across the country, including entomologists, regional epidemiologists, medical officers of health, academics, NGOs, and representatives from the NDCU. This diverse group ensured that the discussions were enriched with practical insights and multidisciplinary expertise.

Dr. Preshila Samaraweera kicked off the workshop with an informative presentation on Sri Lanka’s progress in dengue control, highlighting current research projects and interventions. This set the stage for the D-MOSS training sessions, where participants had hands-on opportunities to test the system and provide feedback.

Training, Feedback, and Collaboration

The D-MOSS platform was well-received, with participants exploring its ability to visualize past, current, and forecasted dengue trends. One participant noted:

“These elements collectively offer a comprehensive view of past, present, and predicted dengue trends, supporting proactive planning and response.”

Following a lunch break, attendees learned about the statistical modeling methods used in E4Warning, with a focus on interpreting probabilistic forecasts. A group discussion then explored ways to enhance the dengue early warning system, including the integration of new data sources such as mobility patterns and socio-economic data. The day concluded with a presentation on the Mosquito Alert platform, sparking a lively conversation about how citizen science could contribute to vector control in Sri Lanka.

Lessons Learned and Next Steps

Reflecting on two intensive days of learning, several valuable lessons emerged from the experience. As highlighted during the workshop discussions, effective dengue control—particularly larval source management—requires a multi-sectoral approach. For example, Aedes mosquitoes often breed in artificial containers that fall under the responsibility of different sectors, such as road maintenance crews for potholes or port authorities for harbor areas.

Another critical area for improvement is the integration of entomological data into a digital infrastructure. Currently, much of this data is collected on paper, limiting its accessibility and use for coordinated control efforts. Digitizing these records would enhance monitoring, analysis, and intervention strategies.

Additionally, dengue prediction models could be further refined by incorporating mobility patterns and socio-economic census data, offering a more comprehensive understanding of how the disease spreads and where interventions could be most effective.

By continuously enhancing the digital tools developed through the E4Warning project, we aim to support the Sri Lankan National Dengue Control Unit (NDCU) in achieving its ambitious goals for dengue control and prevention.

A recent study, published in Insects with E4Warning participation, explores the residual longevity of sterile male mosquitoes and its significance for understanding their field performance in Sterile Insect Technique (SIT) programs: an eco-friendly vector control method where sterile male mosquitoes are released to mate with wild females, reducing mosquito populations over time.

The study aimed to assess the longevity and quality of sterile and non-sterile male Aedes albopictus mosquitoes by using the “mark-release-recapture” (MRR) method. The findings revealed several important insights:

1. Sterile Males’ Longevity: Contrary to expectations, the study found that sterile male mosquitoes had a longer lifespan than their non-sterile counterparts when released into the wild. This extended longevity is a significant advantage for SIT programs, as it increases the likelihood of sterile males mating with wild females, thereby enhancing the effectiveness of population suppression efforts.

2. Effect of Wild Exposure: Sterile males that had been released into the wild lived longer when recaptured and monitored in a laboratory setting. This suggests that exposure to the wild, including factors like fluctuating environmental conditions and access to richer food sources, may improve the performance of sterile males.

3. No Negative Effect of Marking or Sterilization: The process of marking the mosquitoes with fluorescent dyes (following IAEA protocols) and sterilization via gamma radiation did not negatively affect their longevity. This supports the continued use of these practices in SIT programs.

4. Transport and Mass Rearing: Males reared and transported from large-scale production facilities exhibited slightly shorter lifespans compared to those reared locally under small-scale conditions. This suggests that optimizing transportation and rearing conditions can further improve the performance of sterile mosquitoes in the field.

Understanding the longevity and quality of sterile mosquitoes is crucial for optimizing SIT programs, particularly in areas where mosquito populations pose a significant public health threat. The study underscores the importance of refining rearing, sterilization, and transportation techniques to maximize the success of SIT in controlling vector populations and reducing the risk of mosquito-borne diseases.

This research advances our understanding of how sterile males perform in the field, providing valuable insights that can be applied to ongoing and future SIT initiatives and vector dispersal capacity estimation within the E4Warning project.

The study was a collaborative effort involving several institutions and experts across Europe. Key contributors included researchers from the following institutions: Benaki Phytopathological Institute (BPI) in Greece, Centre d’Estudis Avançats de Blanes (CEAB-CSIC), CREAF, and ICREA in Spain, Centro Agricoltura Ambiente “G. Nicoli” in Crevalcore, Italy, Centre for Vectors and Infectious Diseases Research Doutor Francisco Cambournac (CEVDI) at the National Institute of Health Doutor Ricardo Jorge (INSA) in Palmela, Portugal, and the Faculty of Medicine, Environmental Health Institute (ISAMB) at the University of Lisbon, and ASTRE, CIRAD, INRAE, based in La Réunion, France.

Link to the paper: Balatsos, G., Blanco-Sierra, L., Karras, V., Puggioli, A., Costa Osório, H., Bellini, R., Papachristos, D.P., Bouyer, J., Bartumeus, F., Papadopoulos, N.T., & Michaelakis, A. 2024. Residual Longevity of Recaptured Sterile Mosquitoes as a Tool to Understand Field Performance and Reveal Quality. Insects 15, no. 11: 826. https://doi.org/10.3390/insects15110826

You can find other scientific papers produced by E4Warning in our “Publication website”: https://www.e4warning.eu/outputs/publications/

Our partner and WP leader, Rachel Lowe, ICREA Research Professor and Global Health Resilience (GHR) Group Leader at the Barcelona Supercomputing Center (BSC), was recently interviewed by HERA (Health Emergency Preparedness and Response Authority) and featured on their website: https://ec.europa.eu/newsroom/hera/items/852413/en

HERA is an EU body established to strengthen Europe’s ability to anticipate and respond to health emergencies, particularly in the wake of the COVID-19 pandemic. It aims to ensure the provision of critical medical countermeasures and enhance Europe’s readiness for future health threats.

In the interview, Rachel Lowe discusses the intricate connections between climate change and the outbreaks of climate-sensitive infectious diseases, exploring why these outbreaks are increasing and spreading to new regions, particularly in Europe. She also explains how shifting climate patterns could influence emergency preparedness and response strategies, highlighting the need for proactive, integrated approaches. She shared insights into specific climate-sensitive diseases that pose a potential threat to the EU, including dengue, chikungunya, and West Nile virus, and discussed ongoing efforts like the development of the EpiOutlook platform within the IDAlert project, which is part of the European Climate-Health Cluster. This platform aims to provide early warnings of climatic suitability for various infectious diseases in Europe. They also track the impact of climate change on these diseases in the Lancet Countdown in Europe collaboration.

As part of E4Warning, Professor Lowe also elaborated on her work in developing decision support tools like the D-MOSS (Dengue forecasting Model Satellite-based System) for dengue in endemic regions in collaboration with HR-Wallingford, as well the efforts on integrating different data sources such as citizen science initiatives like Mosquito Alert, which could enhance the monitoring and management of disease vectors across Europe, providing critical support for future public health interventions.

For more details, read the full interview on the HERA website and gain valuable insights into how E4Warning and its partners are addressing the growing challenges posed by climate-sensitive diseases in Europe.

Some members of the E4Warning team attended the 23rd ESOVE Conference (European Society for Vector Ecology), held from October 14-17, 2024, in Montpellier, France. This edition was organized by the Vectopole Sud network, which includes research partners from the Occitanie region: Cirad, CNRS, INRAE, IRD, University of Montpellier, Toulouse Veterinary School, and EID Méditerranée, the main public vector control operator in France.

Catuxa Cerecedo (CEAB-CSIC) presented her talk titled “Integrating citizen and authoritative surveillance data in mosquito distribution models,” a study framed within the E4Warning project on the Session Surveillance systems, community-based surveillance and management of VBDs. Her research explores how to integrate mosquito observations collected by citizens using the Mosquito Alert tool with mosquito counts from traditional traps and assesses whether this integration improves habitat suitability models for mosquito species or provides additional insights into mosquito abundances. Exploring the integration of various data sources to model vector dynamics and abundance is one of the project’s key objectives.

The conference also featured presentations from other groups outside the consortium using data collected through Mosquito Alert, as well as studies testing the effectiveness of Vectrack smart traps developed by the partner IRIDEON.

The E4Warning Annual Meeting took place on October 9-10, 2024, in the city of Barcelona. Organized collaboratively by CSIC and UPF, the meeting was hosted at the installations of Pompeu Fabra University (UPF). Representatives from all project partners – CSIC, UPF, BSC, AVIA-GIS, MPG, BPI, IRIDEON, HR Wallingford, and ERGO – came together to discuss the progress and future direction of the project as it concludes its first phase (Periodic Report 1).

The meeting’s agenda covered a wide range of topics, with each partner sharing their latest findings and key challenges encountered so far. Over the two days, the consortium delved into the specific activities carried out by each partner organization, reviewing the fieldwork conducted across various study sites this past summer.

This meeting provided a valuable opportunity for the consortium to assess the progress made in each Work Package (WP), identify scientific gaps, and discuss the risks and measures needed to address issues faced during the project’s first phase. The second day focused on collaboratively planning the next steps for the project’s second phase, with particular attention on identifying key outputs from each task, the steps to transform them into operational tools, and outlining potential outcomes.

Overall, the meeting was a success, providing a solid foundation for the project as it moves forward into its next phase.

In a recent study conducted in Brazil by researchers from the Instituto Oswaldo Cruz, the E4Warning project successfully deployed smart traps with the VECTRACK sensor developed by IRIDEON, to improve mosquito surveillance in urban settings. These smart traps, equipped with AI and IoT technologies, have been tested in two Brazilian cities—Rio de Janeiro and Brasilia—where they demonstrated high accuracy in identifying mosquito species such as Aedes aegypti and Culex quinquefasciatus, both key vectors for diseases like dengue, Zika, and chikungunya.

Over a year of field testing, the traps showed a remarkable 99.8% accuracy in distinguishing target mosquito species from other insects and a 93.7% accuracy in differentiating between the two genera of mosquitoes. The smart traps collected data on 9,151 insect flights, of which 1,383 were mosquito vectors.

These findings indicate the potential of the E4Warning tool to provide real-time monitoring and classification of mosquitoes in areas with high vector-borne disease risks: by the end of September 2024, over 9.5 million dengue cases had been reported in Brazil. In this context, the data gathered from the smart traps could be instrumental in aiding public health authorities to make timely interventions, such as targeted vector control measures, enhancing the preparedness and response to mosquito-borne disease outbreaks.  The successful implementation of the IRIDEON smart traps in Brazil showcases how cutting-edge technologies can revolutionize mosquito surveillance, making it faster, more accurate, and less reliant on manual labor.

The paper has been published in the Parasite & Vector journal: Njaime, F.C.B.F.P., Máspero, R.C., Leandro, A.d., Maciel-de-Freitas, R. Automated classification of mixed populations of Aedes aegypti and Culex quinquefasciatus mosquitoes under field conditions. Parasites Vectors 17, 399 (2024).

It can be consulted at the following link: https://parasitesandvectors.biomedcentral.com/articles/10.1186/s13071-024-06417-z

It can also be founded in the E4Warning Zenodo community: https://zenodo.org/records/13868673

During the summer of 2024, project partners in Spain and Germany have been actively tagging birds with bio-loggers at key study sites to monitor their local and regional movements. Understanding bird movements and space usage during mosquito season is essential, as birds are the primary reservoirs for West Nile Virus (WNV). This project focuses on quantifying the mobility of key reservoir species, filling a crucial gap in current research by examining the local movement and dispersal patterns of resident bird species. Unlike the more extensively studied migratory birds, resident birds’ space usage near human settlements has been less explored. By gathering empirical data on these local movements, we aim to enhance our understanding of how resident bird populations contribute to virus transmission in areas close to human activity.

Fieldwork involves capturing and tagging various bird species with bio-loggers provided by the Max Planck Institute (MPI). For smaller bird species, such as blackbirds (Turdus merula) and starlings (Sturnus vulgaris), we are using bio-logging devices developed by MPI that operate with SigFox technology. Although the SigFox IoT network offers lower spatial accuracy compared to satellite navigation, it supports the creation of particularly small devices thanks to the network’s low power demands requiring fewer electronic components. This allows tracking of smaller species with minimal impact on their natural behaviour.  This innovative technology also allows for near real-time tracking and data transmission to the MovBank platform, making it ideal for monitoring the movements of these smaller species across different environments.

The data collected from these birds will be compared with similar data from other study sites within the project during the next years, allowing us to gain a deeper understanding of the potential WNV transmission dynamics across various landscapes. In addition to blackbirds and starlings, other species being tagged include mallards (Anas platyrhynchos), pigeons (Columba livia), and either western marsh harriers (Circus aeruginosus) or northern goshawks (Accipiter gentilis). The capture and tagging process began in June 2024 and will continue until September 2024, providing valuable insights into how these birds move through different landscapes and potentially contribute to the spread of WNV.

• Read more about the SigFox technology for animal tracking here: A multi-species evaluation of digital wildlife monitoring using the Sigfox IoT network.

In our ongoing efforts to enhance mosquito surveillance and early warning systems, the E4Warning consortium is leveraging innovative technologies, including the improvement of the IRIDEON SL smart-traps. These smart-traps are designed to automate and improve the efficiency of mosquito monitoring, addressing the challenges faced by traditional methods.

Overcoming Traditional Surveillance Challenges

Traditional mosquito surveillance methods are costly and time-consuming, requiring significant professional resources for trap placement, sample collection, and laboratory analysis. Additionally, there is an inevitable time lag between placing traps and collecting samples, which can lead to inaccurate and untimely monitoring of mosquito populations.

The IRIDEON smart traps are off-the-shelf commercial suction traps equipped with the VECTRACK optoelectronic sensor prototype developed by IRIDEON SL in Barcelona. These sensors are capable of distinguishing between mosquito species, sex, and age under both laboratory and field conditions. The VECTRACK sensor includes an emitter, an array of LEDs, and photo-transistors acting as photoreceptors, all working together to create a light field. When a mosquito is drawn into the trap, its wing flapping modulates the light field, generating a species-specific signature. This signature is processed using AI methods, including rule-based systems, genetic algorithms, artificial neural networks, and fuzzy models, to classify the mosquito by genus, species, sex, and age.

Each VECTRACK recording includes GPS coordinates, date and time of capture, ambient temperature, and relative humidity. Every 30 minutes, the field sensor transmits data batches to the server via the mobile phone network. The server then classifies each mosquito event, providing detailed and accurate data on mosquito populations in real-time. This automation reduces the need for manual intervention and enables continuous monitoring.

Field Performance and Global Testing

The VECTRACK sensor has demonstrated its effectiveness in real-world scenarios, achieving high accuracy in field trials conducted in Spain. In El Prat de Llobregat (2021) and Rubí (2022), the sensor achieved 95.5% accuracy in species detection and 88.8% accuracy in classifying the genus and sex of mosquitoes. Check the work performed by Gozález-Pérez et al.: Field evaluation of an automated mosquito surveillance system which classifies Aedes and Culex mosquitoes by genus and sex. Parasites Vectors 17, 97 (2024). https://doi.org/10.1186/s13071-024-06177-w

Ongoing Field Tests Under E4Warning

The E4Warning project is testing the efficacy of the IRIDEON smart-traps under various conditions:

• Spain (Barcelona): VECTRACK sensors are deployed at five strategic monitoring sites across the city, focusing on Culex pipiens and Aedes albopictus. Agència de Salut Pública de Barcelona – ASPB
• Brazil (Rio de Janeiro and Brasilia): Field trials with local populations of Aedes aegypti and Culex quinquefasciatus in collaboration with Instituto Oswaldo Cruz, Fiocruz. Fundação Oswaldo Cruz (Fiocruz)
• Spain (Girona): Testing in non-urban environments like the Botanical Garden of Blanes and Aiguamolls de l’Empordà Natural Park, where diverse mosquito species are present. CSIC
• Greece (Athens): Planned deployment in the Attica region, focusing on critical points of entry for Aedes aegypti and areas of significant vector importance. Benaki Phytopathological Institute

To learn more about IRIDEON smart-traps refer to:

• González-Pérez, M.I., Faulhaber, B., Aranda, C. et al. Field evaluation of an automated mosquito surveillance system which classifies Aedes and Culex mosquitoes by genus and sex. Parasites Vectors 17, 97 (2024). https://doi.org/10.1186/s13071-024-06177-w
• González-Pérez MI, Faulhaber B, Williams M, Brosa J, Aranda C, Pujol N, et al. A novel optical sensor system for the automatic classification of mosquitoes by genus and sex with high levels of accuracy. Parasit Vectors. 2022;15:190. https://doi.org/10.1186/s13071-022-05324-5.

During the E4Warning project, we are employing various methods to collect blood-engorged female mosquitoes to study their feeding patterns. The techniques include carbon-dioxide-baited BG-traps, mechanical aspiration with a powered vacuum aspirator, and artificial resting sites. Sampling began in April 2024 and will continue monthly until November 2024 for this year.

From June 10-15, we hosted Dr. Nathan Burkett-Cadena and Tanise Steen from the Florida Medical Entomology Laboratory, University of Florida, at our study area in Aiguamolls de l’Empordà (Girona, Spain). Their visit aimed to test these collection techniques and share their expertise. They brought vacuum aspirators and resting traps developed by their lab to evaluate their combined efficacy in capturing blood-fed female mosquitoes across different habitats.

The Florida researchers developed human-powered resting traps designed for cavity-resting mosquitoes like Culex. These traps, set among vegetation in dark areas, attract mosquitoes seeking refuge during the day. Traps are placed horizontally to attract Culex and vertically to attract Anopheles mosquitoes and are collected the following day.

To maximize mosquito collection, we combined resting shelter traps and BG-traps with a large-diameter aspirator. These aspirators, designed by Dr. Burkett-Cadena’s team, use an automotive radiator fan to create directional airflow, capturing mosquitoes in a mesh-bottom plastic collection cup.

The insights gained during this visit and throughout the 2024 mosquito season will help finalize protocols for capturing blood-fed females, aiding in our study of mosquito feeding patterns.

• Burkett-Cadena. 2011. A wire-frame shelter for collecting resting mosquitoes. Journal of the American Mosquito Control Association 27: 153–155
• Burkett-Cadena et al. 2019. Human-powered pop-up resting shelter for sampling cavity-resting mosquitoes. Acta Tropica 190: 288-292
• Sloyer et al. 2022. Evaluating sampling strategies for enzootic Venezuelan equine encephalitis virus vectors in Florida and Panama. PLoS Negl Trop Dis.16:e0010329
•  Jaworski et al. 2022. Artificial resting sites: An alternative sampling method for adult mosquitoes. Medical and Veterinary Entomology 36: 139–148

In April, Frederic Bartumeus and Alex Richter-Boix, members of the CSIC and Mosquito Alert team had the opportunity to participate in the WSA Global Congress held in the region of Los Lagos, Southern Chile, as winners of the WSG 2023.

At the congress, the team presented the Mosquito Alert tool developed by CSIC and UPF, an integral part of the E4Warning project aimed at enhancing the capabilities of monitoring and managing vectors and mosquito-borne diseases. Over recent years, the tool has proven its effectiveness and impact by detecting the early presence of invasive mosquitoes –like the tiger mosquito Aedes albopictus– that can act as vectors, as well as capturing and modelling the dynamics of their populations, contributing to improving the management of mosquitoes in cities like Barcelona, Spain, in collaboration with the Public Health Agency of Barcelona (ASPB) which are also partners of E4Warning.

The theme of this year’s WSA Congress, “planet_hack_,” was aptly chosen to highlight the urgent need to address climate change and the expanding opportunities for technological and environmental innovations that accompany this challenge. Participation in the event allowed to not only share the achievements and the impacts of the Mosquito Alert tool but also to engage with other innovators, fostering a network of contacts.

The congress was a celebration of impact entrepreneurship, aligning perfectly with the UN’s global goals and providing a platform for like-minded pioneers to connect and exchange ideas. The team returned energized, ready to build on the substantial progress already made in public health surveillance and excited about the promising new collaborations that arose from this inspiring event.

Read more about the event and the 2023 winner’s catalog here: https://wsa-global.org/2024/01/10/wsa-global-congress-2024-goes-chile/