Dade County Research Articles

Towards geospatially-resolved public-health surveillance via wastewater sequencing

Wastewater is a geospatially- and temporally-linked microbial fingerprint of a given population, making it a potentially valuable tool for tracking public health across locales and time. Here, we integrate targeted and bulk RNA sequencing (N = 2238 samples) to track the viral, bacterial, and functional content over geospatially distinct areas within Miami Dade County, USA, from 2020-2022. We used targeted amplicon sequencing to track diverse SARS-CoV-2 variants across space and time, and we found a tight correspondence with positive PCR tests from University students and Miami-Dade hospital patients. Additionally, in bulk metatranscriptomic data, we demonstrate that the bacterial content of different wastewater sampling locations serving small population sizes can be used to detect putative, host-derived microorganisms that themselves have known associations with human health and diet. We also detect multiple enteric pathogens (e.g., Norovirus) and characterize viral diversity across sites. Moreover, we observed an enrichment of antimicrobial resistance genes (ARGs) in hospital wastewater; antibiotic-specific ARGs correlated to total prescriptions of those same antibiotics (e.g Ampicillin, Gentamicin). Overall, this effort lays the groundwork for systematic characterization of wastewater that can potentially influence public health decision-making.

Effects of Hurricane Irma on mosquito abundance and species composition in a metropolitan Gulf coastal city, 2016–2018

Mosquitoes are the most common disease vectors worldwide. In coastal cities, the spread, activity, and longevity of vector mosquitoes are influenced by environmental factors such as temperature, humidity, and rainfall, which affect their geographic distribution, biting rates, and lifespan. We examined mosquito abundance and species composition before and after Hurricane Irma in Miami, Dade County, Florida, and identified which mosquito species predominated post-Hurricane Irma. Our results showed that mosquito populations increased post-Hurricane Irma: 7.3 and 8.0 times more mosquitoes were captured in 2017 than at baseline, 2016 and 2018 respectively. Warmer temperatures accelerated larval development, resulting in faster emergence of adult mosquitoes. In BG-Sentinel traps, primary species like Ae. tortills, Cx. nigripalpus, and Cx. quinquefasciatus dominated the post-Hurricane Irma period. Secondary vectors that dominated post-Hurricane Irma include An. atropos, An. crucians, An. quadrimaculatus, Cx. erraticus, and Ps. columbiae. After Hurricane Irma, the surge in mosquito populations in Miami, Florida heightened disease risk. To mitigate and prevent future risks, we must enhance surveillance, raise public awareness, and implement targeted vector control measures.

Characterization of the Spatial Distribution of the Pepper Weevil, Anthonomus eugenii Cano (Col.: Curculionidae), in Pepper Fields in South Florida.

The pepper weevil, Anthonomus eugenii Cano, is an economically important pest of cultivated peppers (Capsicum annuum) in tropical and subtropical regions of the world. This study aimed to ascertain the spatial distribution of pepper weevil infestation across various fields in Miami Dade County, South Florida. The spatio-temporal dynamics of pepper weevil were evaluated using 144 sample points within each of seven pepper fields. The data were analyzed using three different geospatial techniques, spatial analysis by distance indices (SADIE), Moran's I, and Geary's C, to determine the spatial distribution of pepper weevil. The SADIE analysis revealed a significant aggregation distribution in 18 out of 30 sampling dates across all fields. The results from Geary's C and Moran's I indices indicated a positive spatial autocorrelation (spatial clustering/aggregation) of pepper weevil regardless of field or pepper types. Overall, the findings from this study depict an aggregated spatial distribution pattern of pepper weevil populations, characterized by a tendency for aggregation that transitions to a more uniform distribution as the season progresses.

Arthropod Diversity in an Urban Forest from Miami Dade County, Florida, US

Arthropods are excellent candidates for studying how the formation of urban ecosystems impacts the environment for several reasons. Foremost of these is the variety of roles played by arthropods in ecosystem functioning (e.g., food web dynamics, nutrient cycling and redistribution, and pollination) with many of these roles being economically important [e.g. pollination by domestic bees is an $18 billion/year industry in the US alone]. Urban ecosystems have been neglected in ecological research. Arthropods are abundant in urban settings, but little is known about how these animals respond to urbanization. In this project, we present data on species composition and structure of the communities of arthropods from Saint Thomas University Urban Forest, in the city of Miami Gardens, Miami Dade County, State of Florida, USA. In order to conduct our samplings, we set up 16 pitfall traps, as is usually done for invertebrate soil biodiversity. We then sorted and identified collected individuals using a Dissecting Microscope. Data were analyzed using PAST to calculate diversity indices of the sites studied and species organization. We collected a total of 31 species distributed in 21 Families and 13 Orders. Most species were identified up to the species level. Total number of individuals was 2147, representing a high abundance. The most abundant species was Solenopsis molesta, represented by 1313 individuals. Invertebrates are sensitive to climatic and ecological alterations. Their small bodies desiccate easily, a factor which may limit their evolutionary response to accelerated temperature increases. Consequently, the understanding, preservation, and development of urban forests can provide an avenue through which the conservation of local communities is sustained, starting with some of its most numerous and ecologically sensitive species.

Health status of childcare center providers in a COVID-19 hotspot.

Childcare center providers in Miami-Dade County, Florida a COVID-19 hotspot, are made up almost entirely of ethnic minority women. This is a critical frontline staff that is now encountering the triple threat of respiratory illnesses from respiratory syncytial virus (RSV), influenza viruses (or the seasonal flu), and COVID-19. To examine sociodemographic characteristics, anthropometrics, and health behaviors that were collected from a sample of CCC teachers in Miami Dade County, a COVID-19 hotspot. Cross-sectional data were used from Healthy Caregivers, Healthy Children (HC2), a randomized controlled intervention trial (#NCT02697565) for healthy weight maintenance among children 2-to-5 years old, conducted in 24 subsidized childcare centers in MDC in 2015-2018. Prevalence was determined by frequency or mean/standard deviation of each variable. Chi-squared analyses were performed to test for differences in BMI categories. In this sample of childcare center providers (n = 255), the majority (61%) had an elevated body mass index. Positive health behaviors such as regular exercise and eating fruits and vegetables were only reported in about a third of the sample. It is vital that we encourage the uptake of regular vaccination schedules as a means to protect our community, especially the critical frontline workers that have been caring for our young children.

Barriers and facilitators to health during prison reentry to Miami, FL.

People face numerous barriers to reentry and community integration following incarceration, and these obstacles manifest themselves as barriers to economic stability, housing security, healthcare, community acceptance, and educational attainment, ultimately leading to poor health. This study aims to understand healthcare needs of reentrants post release within the unique political and service context of Miami Dade County, FL, and seeks to uncover the structural facilitators and barriers to sustaining health during reentry. We report on a subset of data from a larger reentry asset mapping project. We conducted a qualitative thematic analysis based on 12 semi-structured interviews with community stakeholders, including reentrants who were released in the past year (n = 5) and with community providers who have provided support services to returning citizens for at least one year (n = 7). Narratives were coded through an iterative process using NVivo software and were analyzed using the general inductive approach. Three themes emerged from the analysis: (1) social and structural barriers and facilitators to health during reentry, (2) challenges with medical care following release, and (3) long-term impacts of receiving poor healthcare in prison. Reentrants describe the carceral environment as non-conducive to health and cite an urgent need for systemic change within correctional institutions to promote their well-being. Respondents identified substance use disorder (SUD) treatment, trauma informed therapy, and chronic disease management as the primary healthcare needs of reentrants, and cite social support, stable housing, education, and employment as the key social and structural needs upon release. This study identifies prevalent resource gaps in Miami Dade County during reentry. Respondents advocate for more inclusive governmental housing programs, Medicaid expansion, and more holistic reentry programs to support reentrants. Understanding the barriers and facilitators to health during reentry can inform future interventions to better support reentrants in their transition post-incarceration.

Georgia Library Spotlight: Dade County Public Library Promotes Generational Connections Through Pokémon

Georgia Library Spotlight: Dade County Public Library Promotes Generational Connections Through Pokémon

Management of a Globally Imperiled and Fire-Dependent Ecosystem in the Urban Matrix of Miami–Dade County, Florida: A Case Study of the Richmond Tract Pine Rocklands

Pine rockland habitat of South Florida is among the most highly threatened terrestrial ecosystems in the neo-subtropics and is among the rarest worldwide. With only 1.2% of its original extent remaining outside Everglades National Park, fewer than 780 hectares of this ecosystem remains across all of South Florida. This fire-dependent ecosystem—habitat for many rare, endemic species—has experienced substantial deforestation and defaunation due to urbanization, land use change, habitat fragmentation, fire suppression, and exotic plant invasions. Owing to the small size of remaining fragments, and the fact that most are surrounded by urbanization, adequate burning regimes are suppressed. The Richmond Tract, a complex of twelve separate parcels under multiple private and public ownership partially surrounding Zoo Miami, is the largest tract of pine rockland outside the federal protection of Everglades National Park. In this article, we take inventory of the threatened biodiversity at the Richmond Tract and focus on the policy and management landscape. We take a close look at threats to the pine rockland’s persistence here and review approaches that either help maintain the health of this ecosystem or those that may need to be reconsidered. We end by discussing coordination among multiple stakeholder groups, the potential use for incentive-based conservation practices, and suggesting ways to improve management in highly urbanized South Florida.

Miami-Dade County: On the Forefront of Preservation Solutions

Mayor Daniella Levine Cava, the first female mayor of Miami Dade County, describes her administration's efforts to help communities become more climate resilient, to address issues of affordable housing amid immense development, and support small business development through the work of historic preservation

Biomass and Carbon Capture in Trees at Amelia Earhart Park, Miami Dade County, Florida, US

In the context of climate change, scientists strive to look for ways to calculate the constant CO2 emissions as well as carbon sequestration to find solutions to reduce the emission of greenhouse gases. In this context, it is important to recognize that trees within urban environments operate as “carbon sinks” that significantly contribute to the effort of reducing carbon in the atmosphere. During previous studies in biomass and carbon stock determination conducted in the St. Thomas University campus we have found evidence that “urban forests” play an important role in sequestering carbon from the atmosphere and can serve as a foundation for developing biomass recordings within nearby locations, to support the importance of increasing the number of parks and hardwood trees in urban environments that operate as “carbon sinks”. Our project was conducted in the Amelia Earhart Park, in Hialeah, Florida, with the purpose of calculating the amount of Biomass and Carbon Stock produced by the hardwood trees and palm trees in selected areas of the park. Tree perimeters were measured using a tailor’s tape as a first step to determining their biomass. Data transformation and allometric equations were used to determine biomass and carbon stock. The objectives of our project were (1) to determine the average total biomass and carbon stock (expressed in Kg and Mg) in selected locations, 2) compare the biomass and carbon sequestration between hardwood trees and palm trees. The overall biomass was 706,437.95 Kg (706.44 Mg), and overall, Carbon Stock was 332,026 Kg (332.02 Mg. The area sampled constitutes around 25% of the park land area, so if we extrapolate to the whole land area of the park, we could say that the overall biomass would be roughly 2,825,751.80 Kg (2,825.75 Mg), and Carbon Stock ca. 1,328,104 Kg (1,328.10 Mg). In order to calculate the totals, we only used Brown & Iverson equation. In conclusion, total Biomass calculated expressed by area is 33.9 Mg Ha-1, and Carbon Stock is 15.93 Mg Ha-1. This information strongly supports the importance of increasing the number of parks, and hardwood trees in urban environments that operate as “carbon sinks”, and consequently carbon reservoirs. Total Biomass for Hardwood trees was 689,218.93 Kg (689.22 Mg), and Total biomass for Palm Trees was 17,219.02 Kg (17.22 Mg) (Tables 3 to 8). Differences in Biomass between hardwood trees, and palm trees, are very significant (T= 7.67, p< 0.01). Between the palm trees and hardwood, 16 species were identified in different areas of the Amelia Earhart Park. Of the palm trees, Sabal palmetto and Sabal mexicana palm are the most abundant with over 68 trees in total. Of hardwood trees, Casuarina equisetifolia and Quercus virginiana are the most abundant with over 430 trees combined.

Addressing COVID-19 Misinformation and Resiliency Among Latinos Living With HIV: Formative Research Guiding the Latinos Unidos Microgame Intervention

Besides the risk of coronavirus disease 2019 (COVID-19) itself, the indirect and unprecedented effects of mitigation strategies including shelter-in-place orders and social distancing combined with the widespread COVID “infodemic” disseminated by media interacted synergistically to worsen already compromised mental health outcomes of Latino people living with HIV (PLWH). This funded project directly addresses the sources of health disparity in Miami Dade County: mental health and misinformation by developing a culturally tailored resilience and media literacy intervention for Latinos living with HIV. Extant research on resilience strategies and media literacy skills have documented their effectiveness in assisting individuals make realistic appraisals and informed decisions that could benefit their health outcomes and improve health-related challenges. We utilized a community-based approach by collaborating with two local community partners (Open Arms and Borinquen) and conducting 27 qualitative interviews with Latino PLWH, infectious disease providers, and community health workers who directly informed content of the Latino Unidos microgame intervention. This article describes the formative research process guiding the Latinos Unidos microgame intervention—a three-module gamified intervention. Study outcomes provide the foundation for media and educational strategies that increase adherence to health guidance and enhance mental health responses to adversity as a response to the COVID-19 pandemic.

Punishing Neighborhood “Outsiders”: Neighborhood Punishment Rates and the Spatial Mis(match) Between Defendants’ Residence and Arrest Locations

This study examines how “outsider” arrests (i.e., arrests that happen in neighborhoods where defendants do not reside) and other covariates impact community-level punishment outcomes. Using census tract-level data on drug, violent, and property crime arrests occurring in Miami- Dade County (Florida) between 2012 and 2015, we estimate negative binomial regression models across three key punishment stages (pretrial detention, conviction, incarceration). Our findings suggest neighborhoods with higher levels of “outsider” cases, concentrated disadvantage, and Black defendants experience significantly higher rates of pretrial detention, conviction, and incarceration, net of controls. These findings vary across crime types, implying that such factors may also shape court actors’ focal concerns regarding neighborhood outsiders and other demographic factors. We discuss implications and directions for future research.

Addressing Food Insecurity during the COVID-19 Pandemic: Intervention Outcomes and Lessons Learned from a Collaborative Food Delivery Response in South Florida's Underserved Households.

Background: The COVID-19 pandemic highlighted underlying disparities in health, healthcare access, and other social factors that have been documented for racial/ethnic minorities. The social-distancing mandate exacerbated the impact of social determinants of health, such as unemployment and food insecurity, particularly among underserved minority populations. We highlight intervention outcomes and lessons learned from the Florida International University (FIU) Herbert Wertheim College of Medicine (HWCOM) NeighborhoodHELP’s response to pandemic-related food insecurity among Miami Dade County’s underserved population. Methods: Following the stay-at-home mandate, a weekly needs assessment of program households was conducted by the NeighborhoodHELP team, during which food insecurity emerged as a pandemic-related urgent need, rising from three percent of program Households in March 2020 to 36.9 percent six months later. Consequently, the program staff collaborated with another FIU department, community partners, and a benefactor to develop a food donation and delivery project. Results: Fifteen hundred and forty-three culturally appropriate food boxes were delivered to 289 participating households, comprising 898 household members, over a 14-month period. Conclusion: This project underscores the importance of leveraging community assets to address their needs during a crisis and the significance of sustained community engagement for researchers and service providers who work in underserved communities.

Application of the Concrete Stressmeter for Augered Cast-in-Place (ACIP) Deep Foundation Testing

The conventional method of computing forces from strain gage data during deep foundation load testing relies on knowing the cross-sectional area and Young’s Modulus of the pile’s concrete or grout. Errors in estimating these parameters directly affect the computed force distribution of the foundation element being tested. Since the standard formulas were derived for concrete with coarse aggregates, the problem of estimating Young’s Modulus for augered-cast-in-place (ACIP) piles or other piles constructed with grout is compounded by the lack of mathematical relationships for converting grout strength into modulus of elasticity. Concrete Stressmeters (CSMs) are instruments designed to overcome these difficulties and directly measure unidirectional stress in cementitious materials. The instrument design creates a load cell out of the in-place cementitious material itself, with the same elastic properties as the surrounding material. This study discusses the installation and data analysis of two ACIP bi-directional static load test (BDSLT) piles instrumented with CSMs, to validate the use of these instruments as an alternative to strain gages. The first test pile had a nominal diameter of 610 mm and a length of 26 m; the second test pile had a diameter of 760 mm diameter and a length of 35 m. Both piles were installed in Dade County, Florida, in alternating layers of sand and limestone. CSMs installed using the self-filling method yielded excellent comparison to force values derived from strain gages. An error analysis indicated a potential order of magnitude improvement in the accuracy of computed forces using the stressmeters as opposed to the strain gages, due to minimal reliance on an estimated Young’s Modulus. The two case histories yielded comparable and reasonable force distributions with considerably less effort and fewer assumptions. The paper aims to stimulate the discussion and development of reliable alternatives to traditional strain-gage based analyses.

Lessons from a Landscape Irrigation Rebate Program in Miami Dade County

We calculated savings in outdoor water uses from 37 properties in Fisher Island, Florida, that were retrofitted with smart Evapotranspiration-based irrigation controllers through the Miami Dade County’s Landscape Irrigation Rebate Program. We found average water savings of 11.4 million gallons per year from the 37 properties on the island. We discuss the roles of extension personnel in developing and effectively managing an irrigation rebate program and the implications of results from this program for large scale efforts towards efficient use of freshwater resources.

The role of phylogenetic scale in Darwin's naturalization conundrum in the critically imperilled pine rockland ecosystem

AbstractAimWe expand on community phylogenetic approaches to Darwin's Naturalization Conundrum by considering phylogenetic scale, comprised of phylogenetic grain and extent. We assess relatedness between invasive, non‐native and native plant species at multiple depths in the phylogeny (i.e. phylogenetic grain) and across multiple clades (i.e. phylogenetic extents) at regional and local spatial scales in the highly fragmented, critically imperilled pine rockland ecosystem.LocationMiami‐Dade County, Florida, USA.MethodsWe used two metrics differing in phylogenetic grain to determine whether invasive or non‐native species were more closely related to native species in the regional pool and at 33 habitat fragments. At both spatial scales, we altered phylogenetic extent from all vascular plants to four smaller phylogenetic domains (Monilophyte, Gymnosperm, Monocotyledon and Dicotyledon) and assessed whether the interpretation of relatedness changed.ResultsFor the regional pool and at a broad phylogenetic grain, non‐native species were more closely related to the native community than invasive species were for all phylogenetic extents (i.e. support for Darwin's Naturalization Hypothesis, DNH), and at a fine phylogenetic grain for only two phylogenetic extents. At the local scale, there was limited support for DNH across all phylogenetic extents. In Monocotyledons, support for DNH was more prevalent at the fine phylogenetic grain, while Dicotyledons showed support for DNH at the broad phylogenetic grain.Main conclusionsIn the pine rockland flora, we found either support for DNH or no difference in relatedness between non‐native‐to‐native and invasive‐to‐native species. However, patterns of relatedness varied across spatial and phylogenetic grain and, critically, this variability is highly dependent on the phylogenetic extent considered. By explicitly assessing the interactions between spatial scale and phylogenetic scale, we show that support for DNH was context dependent, and findings at smaller phylogenetic extents rarely agreed with findings at the larger phylogenic extent.

Caring for Vulnerable Communities in Miami Dade County during the COVID-19 Pandemic

In response to the COVID-19 pandemic, the Herbert Wertheim College of Medicine's Neighborhood Health Education Learning Program (NeighborhoodHELP) initiated a longitudinal assessment and mitigation of social and health care challenges for a population of approximately 850 underserved households. Here, we describe the needs assessment, ensuing interventions, and lessons learned during this pandemic.

Variation in Risk of COVID-19 Infection and Predictors of Social Determinants of Health in Miami-Dade County, Florida.

Miami–Dade County zip code–level (N = 91 zip codes) coronavirus disease 2019 (COVID-19) cases (N = 89,556 as of July 21, 2020) reported from the Florida Department of Health were used to estimate rates of COVID-19 per 1,000 population at the census block group level (N = 1,594 study block groups). To identify associations between rates of COVID-19 infections and multidimensional indexes of social determinants of health (SDOH) across Miami–Dade County, Florida, I applied a global model (ordinary least squares) and a local regression model (geographically weighted regression). Findings indicated that a social disadvantage index positively affected COVID-19 infection rates, whereas a socioeconomic status and opportunity index and a convergence of vulnerability index had an inverse but significant connection to COVID-19 infection rates over the study area. Rates of COVID-19 infections were localized to specific geographic areas and ranged from 0 to 60.75 per 1,000 population per square mile.

<p class="Body"><strong>The Tetranychoidea, Tarsonemidae and Tydeoidea mite complex on Florida citrus between 1954 and 2014: pests or beneficials?</strong></p>

A survey of the mite fauna on citrus was conducted in 542 dooryard trees in the following counties: Dade (24), Broward (127), Palm Beach (68), Martin (35), St. Lucie (20), Indian River (11), Collier (23), Lee (37), Charlotte (20), Sarasota (67), Manatee (18), Pinellas (59), Polk (32), and Highlands (1) to update our knowledge of the mite complex on Florida citrus. We also sampled 25 varietal citrus trees at two research centers in Polk and Dade Counties. A third block of 'Tahiti' lime trees was sampled at the Tropical Research & Education Center in Dade County. At least 787 commercial citrus trees were also sampled in Florida between 2009 and 2014. Here we report the frequency and occurrence of the Tetranychoidea, Tarsonemidae and Tydeoidea on those trees. Previous field studies of the Tarsonemidae and Tydeoidea on citrus in Florida between 1993-2003, a horticultural mineral oil (HMO) field study during 1994-1996 and M. H. Muma from 1961-1975 are included for comparison. Eutetranychus species near orientalis was collected from a lemon tree in Broward County. This is a new record of this species on Florida citrus. Additional new records of mites on Florida citrus include Tarsonemidae: Fungitarsonemus setillus Sousa et al, Tarsonemus confusus Ewing, and Tarsonemus waitei Banks; Tydeoidea: (Iolinidae)- Parapronematus n sp, Neopronematus n sp; (Triophtydeidae): Triophtydeus immanis Kuznetzov, T. n sp; (Tydeidae): Afrotydeus n sp, Brachytydeus sp near australiensis, B. n sp, Pretydeus sp near reticulatus, and Tydeus sp near munsteri. Seven species of tarsonemids were collected from dooryard and varietal block citrus during the 2009-2014 survey compared with one species from commercial citrus trees. A total of 27 species of Tarsonemidae were collected from citrus in Florida between 1954 and 2014. Thirteen species of Tydeoidea were collected from dooryard and varietal block citrus trees during the 2009-2014 survey compared with 4 species from commercial citrus trees. A total of 31 species of Tydeoidea were collected from citrus in Florida between 1961-2014. The roles that different species of tarsonemid and tydeoid mites have as plant feeders, fungivores, mycophages, or predators of one or more phytophagous mites are discussed.

Color slices analysis of land use changes due to urbanization in a city environment of Miami Area, South Florida, USA

Land use maps are widely using all over the world for monitoring the usage of lands over a while when urbanization booms. The urban development of the city environment parallelly involves the quick change of landcover in a short time. This work aims to review the land cover changes in Miami which areone of a highly urbanized county in the USA in the twentieth century. The color patterns of land use maps were reviewed with a uniform temporal rate (5 years once) from 2001 to 2016. Based on the color code of the image, land use maps were visually interpreted and it was extended to the Statistical analysis. Unique formulas are derived from the linear statistical model for the changing rate of the land use type in 15 years. Urban built-up gave expeditious increment in land use (9.5%). In the meantime, agricultural land (5.97%) and water (4.21%) decreased at a rapid rate. At the end of the study, the regression model projects the land use change in the year 2021 in Miami Dade County. This study distinctly exhibits how urbanization affects the vegetation cover, water areas, and wetlands, in which land use classes playing a vital role in the ecosystem. This experiment gives a basic understanding of Miami Dade county development and its environmental impact.