In response, researchers at the University of California San Diego and public health officials from the County of San Diego Health and Human Services Agency have developed a county-level dashboard designed to track and forecast the threat. The tool integrates confirmed screwworm detections, environmental conditions favorable to the fly and its larvae, and information gathered from news reports. Together, these data streams generate regional risk profiles intended to help officials identify where cases may emerge next and how quickly the threat could advance.

New World screwworm is the larval stage of the blowfly Cochliomyia hominivorax. Unlike the larvae of most flies, which feed on dead or decaying material, screwworm larvae invade living tissue. Female flies typically deposit eggs in wounds or natural openings of mammals and other warm-blooded animals. After hatching, the larvae burrow deeper into healthy flesh, enlarging the wound and creating conditions for secondary bacterial infections. Untreated infestations can cause severe injury and death, particularly in livestock, newborn animals and wildlife.

People can also be affected, although human infestations are uncommon and the parasite does not spread directly from person to person. Infection occurs when flies lay eggs in an open wound or near mucous membranes. The resulting larvae must be removed through prompt medical care, since continued feeding can produce extensive tissue damage. Because the screwworm is not a conventional contagious pathogen, its expansion depends largely on the movement of infested animals, suitable climate conditions and the availability of hosts rather than on human-to-human transmission.

The new dashboard is intended to provide an early-warning system before conventional public health reporting is complete. Laboratory confirmation of an animal infestation can take days or weeks, while media reports, veterinary observations and other early signals may reveal a developing problem sooner. By combining these sources with environmental suitability models, the system can estimate whether a county is likely to face increasing risk and help officials determine whether preparations are needed immediately or over a longer planning horizon.

Environmental modeling is central to the tool’s design. The screwworm’s ability to establish itself depends on temperature, humidity, host availability and other ecological factors that influence adult survival, reproduction and larval development. The dashboard uses these conditions to assess how suitable a region may be for the fly and its offspring. It also accounts for the pest’s capacity to travel considerable distances and for its potential transport through livestock, pets, birds and other wildlife. The resulting estimates do not predict individual cases with certainty, but they provide a structured way to compare risk across counties and over time.

Officials in San Diego County say the system is especially valuable because California has extensive livestock, veterinary and wildlife networks that could detect suspicious cases. The county is working with the California Department of Food and Agriculture to connect veterinarians with surveillance resources and guidance. Since screwworm can affect nearly any warm-blooded animal, cooperation among livestock veterinarians, companion-animal practitioners, wildlife specialists and public health agencies will be essential. Early recognition of wounds containing larvae could limit local transmission and improve the chances of rapid containment.

The United States previously eliminated New World screwworm through one of the most successful biological control programs ever attempted. The campaign relied on the sterile insect technique, in which large numbers of radiation-sterilized male flies were released into affected areas. When sterile males mated with wild females, the resulting eggs failed to produce viable offspring, causing populations to collapse over successive generations. Current eradication efforts, led by the U.S. Department of Agriculture, are again using sterile insects alongside pesticides and restrictions on animal movement. Regulators are also considering a genetically modified, all-male strain now undergoing field testing, while UC San Diego researchers are exploring additional genetic technologies that could improve future control strategies.

The dashboard is being developed through Resilient Shield, a UC San Diego initiative and Centers for Disease Control and Prevention-funded center that forms part of the national Insight Net outbreak and disease modeling network. Its model reverses the traditional relationship between researchers and public agencies: instead of developing tools based only on academic priorities, public health organizations submit specific requests, or “tickets,” describing urgent operational needs. Resilient Shield then assembles data systems, simulations, secure computing and other technical resources to create a targeted response. The screwworm project illustrates how epidemiologists, engineers, veterinarians and data scientists can work together to convert fragmented information into an actionable warning system.

The dashboard is currently available only to project partners and public health officials, although its developers hope to release a public version. Its broader significance lies in the architecture behind it. By using an open and modular design, the same infrastructure can potentially be adapted to monitor other threats involving human disease, animal health, environmental change and weather. For communities facing emerging biological hazards, the goal is not simply to document outbreaks after they occur, but to recognize the combination of ecological and social signals that may indicate where the next outbreak is most likely to appear.

Subject of Research: Animals

Article Title: A New World Screwworm Dashboard Helps Public Health Officials

Web References: UC San Diego Resilient Shield; County of San Diego Public Health Services; USDA Stop Screwworm Hub; California Department of Food and Agriculture; Insight Net

Image Credits: Scott Blair/UC San Diego Qualcomm Institute

Keywords: New World screwworm, Cochliomyia hominivorax, epidemiology, parasitology, animal health, public health, disease surveillance, computational modeling, sterile insect technique, livestock disease, environmental risk assessment

Phthalates, a class of commonly used plasticizers, are ubiquitous in consumer products and have raised concerns due to their endocrine-disrupting properties and potential links to various health problems including reproductive disorders and metabolic diseases. Their presence in everyday settings complicates accurate exposure assessments, which historically relied on environmental sampling or biomonitoring, each with inherent limitations. Environmental sampling can underestimate true personal exposure by failing to capture all exposure routes, while biomonitoring, typically through urinary biomarkers, though direct, presents challenges related to temporal variability and invasive sample collection.

Ferris and colleagues’ study introduces a promising approach that synergistically leverages silicone wristbands—worn continuously to passively adsorb ambient phthalates—and rigorous urinary biomarker quantifications. These dual modalities enable a more comprehensive and temporally resolved snapshot of phthalate exposure. Silicone wristbands possess unique physicochemical properties, making them excellent passive samplers for a broad range of semi-volatile organic compounds, including phthalates. Their ability to integrate exposure across various microenvironments renders them particularly attractive for real-world exposure assessment, as they capture not only inhalation but also dermal and incidental ingestion routes.

The research meticulously recruited participants from diverse demographic backgrounds, ensuring broad applicability of findings. Subjects were instructed to wear silicone wristbands for predefined durations while providing urine samples at intervals. Analytical chemistry techniques, including gas chromatography coupled with mass spectrometry, were employed to quantify individual phthalate metabolites in biological matrices and corresponding parent compounds in wristbands. This integrative strategy allowed the researchers to explore correlations between external exposure via the wristbands and internal dose reflected in urinary metabolites.

Initial findings revealed a significant concordance between the silicone wristband-derived phthalate concentrations and urinary biomarker levels, suggesting that wristbands serve as proxies for personal exposure. Interestingly, wristband data provided enhanced temporal resolution compared to spot urine samples, which often reflect acute exposure and suffer from temporal fluctuations. The research team also noted inter-individual variability in exposure profiles, which the wristband effectively captured, indicating its utility for personalized exposure assessment and potential for identifying exposure hotspots in individuals’ daily environments.

Beyond correlational analysis, the study interrogated the sensitivity and specificity of silicone wristbands compared to conventional biomonitoring. Results suggested that wristbands could detect lower-level exposures that might be missed by single biomarker measurements due to biological metabolism and excretion kinetics. This implies potential advantages in epidemiological studies aiming to link low-dose phthalate exposure with subtle health outcomes, where traditional biomonitoring might fall short due to exposure misclassification.

Ferris et al. also delved into the biochemical implications of their findings by examining how exposure patterns detected via wristbands align with known toxicodynamic behaviors of phthalates. Given that phthalates are metabolized rapidly and excreted within hours, the wristband’s ability to sample a cumulative environmental milieu over days provided a valuable integrative lens. This temporal integration overcomes the snapshot limitations of urine sampling, offering a stable metric against which physiological responses and health outcomes may be correlated in future longitudinal studies.

The approach developed in this study exemplifies a broader paradigm shift towards non-invasive, passive environmental sampling as a complement or alternative to traditional biospecimen collection. The simplicity and user compliance advantages of wristbands—being lightweight, unobtrusive, and requiring minimal participant burden—position them as ideal tools for large-scale population studies. Such scalability is crucial for advancing exposomic research, which seeks to characterize the totality of environmental exposures throughout the lifespan.

Moreover, the study’s multi-disciplinary approach, integrating environmental chemistry, toxicology, and epidemiology, underscores the potential for cross-sector collaboration in environmental health sciences. It paves the way for next-generation exposure monitoring frameworks that could inform personalized risk mitigation strategies and regulatory decision-making. Understanding personal exposure profiles with heightened accuracy and resolution may eventually translate into precision public health interventions tailored to unique environmental contexts.

The team also discussed potential limitations and challenges facing widespread adoption of silicone wristbands for exposure assessment. These include standardization of analytical protocols, understanding the kinetics of compound absorption to and desorption from wristband matrices, and ensuring the specificity of detected chemicals to personal versus ambient environments. Addressing such technical nuances is crucial to optimize data interpretation and comparability across studies and populations.

Future research directions proposed by Ferris and colleagues encompass expanding the chemical scope monitored by wristbands beyond phthalates to include other emerging contaminants such as flame retardants, pesticides, and volatile organic compounds. Additionally, integrating sensor technologies with wristbands could enable real-time monitoring and enhance data richness. Combining chemical exposure data with genomics and metabolomics may also unlock comprehensive insights into exposure-disease relationships.

This innovative study exemplifies the forward trajectory of exposure science, where synergy between novel passive sampling techniques and biomarker science fosters more accurate, comprehensive, and individualized exposure assessments. Such advancements hold promise not only for elucidating environmental determinants of health but also for empowering individuals and communities with actionable exposure knowledge. The work by Ferris et al. is thus a clarion call to embrace technological ingenuity in the quest to unravel the complex web of environmental influences shaping human health in the 21st century.

As scientific communities digest these findings, public health agencies and stakeholders may soon consider adopting silicone wristbands as complementary tools in exposure monitoring programs. This transition could catalyze the implementation of more nuanced exposure guidelines and interventions designed to mitigate the risks posed by phthalates and similar environmental contaminants. Ultimately, such strides bring us closer to a future where personalized environmental health is not an aspiration but a tangible reality, rooted in meticulous science and innovative methodologies.

In synopsis, the confluence of silicone wristband technology with urinary biomarker analysis represents a methodological leap forward. The precise yet non-invasive measurement of phthalate exposure crafted by Ferris and collaborators heralds a new era in environmental epidemiology. By bridging external exposure assessment and internal dose quantification, this integrated framework propels our understanding of chemical exposures in daily life and their implications on health, thereby setting the stage for improved risk assessment and impactful public health policies worldwide.

Subject of Research:
Article Title:
Article References:

Ferris, A.J., Riley, K.W., Calero, L. et al. Evaluating the use of silicone wristbands and urinary biomarkers to assess personal exposure to phthalates. J Expo Sci Environ Epidemiol (2026). https://doi.org/10.1038/s41370-026-00899-y

Image Credits: AI Generated
DOI: 28 April 2026
Keywords: Silicone wristbands, phthalate exposure, urinary biomarkers, personal exposure assessment, environmental health, passive sampling, endocrine disruptors.