Leptospirosis has recently been reported as an emerging disease worldwide, and a seroprevalence study was undertaken in American Samoa to better understand the drivers of transmission. Antibodies indicative of previous exposure to leptospirosis were found in 15.5% of 807 participants, predominantly against three serovars that were not previously known to occur in American Samoa. Questionnaires and geographic information systems data were used to assess behavioral factors and environmental determinants of disease transmission, and logistic regression was used to identify factors associated with infection. Many statistically significant factors were consistent with previous studies, but we also showed a significant association with living at lower altitudes (odds ratio [OR] = 1.53, 95% confidence interval [CI]: 1.03–2.28), and having higher numbers of piggeries around the home (OR = 2.63, 95% CI: 1.52–4.40). Our findings support a multifaceted approach to combating the emergence of leptospirosis, including modification of individual behavior, but importantly also managing the evolving environmental drivers of risk.

Abstract

Strategies that block infiltration of leukocytes into the injured spinal cord improve sparing of white matter and neurological recovery. In this article, we examine the dependency of recovery on hematogenous depletion of neutrophils and monocytes. Mice were depleted of neutrophils or monocytes by systemic administration of anti-Ly6G or clodronate-liposomes. A third group was depleted of both subsets. Neurological improvement, based on a battery of tests of performance, and white matter sparing, occurred only in animals depleted of both neutrophils and monocytes. We also attempted to define the nature of the environment that was favorable to recovery. Hemeoxygenase-1 and malondialdehyde, markers of oxidative stress and lipid peroxidation, respectively, were reduced to similar levels in animals depleted of both neutrophils and monocytes, or only monocytes, but remained elevated in the group only depleted of neutrophils. Matrix metalloproteinase-9, a protease involved in early damage, was most strongly reduced in animals depleted of both leukocyte subsets. Finally, disruption of the blood–spinal cord barrier and abnormal nonheme iron accumulation were reduced only in animals depleted of both neutrophils and monocytes. Together, these findings indicate cooperation between neutrophils and monocytes in mediating early pathogenesis in the contused spinal cord and defining long-term neurological recovery.

Background

The recent emergence of leptospirosis has been linked to many environmental drivers of disease transmission. Accurate epidemiological data are lacking because of under-diagnosis, poor laboratory capacity, and inadequate surveillance. Predictive risk maps have been produced for many diseases to identify high-risk areas for infection and guide allocation of public health resources, and are particularly useful where disease surveillance is poor. To date, no predictive risk maps have been produced for leptospirosis. The objectives of this study were to estimate leptospirosis seroprevalence at geographic locations based on environmental factors, produce a predictive disease risk map for American Samoa, and assess the accuracy of the maps in predicting infection risk.

Methodology and Principal Findings

Data on seroprevalence and risk factors were obtained from a recent study of leptospirosis in American Samoa. Data on environmental variables were obtained from local sources, and included rainfall, altitude, vegetation, soil type, and location of backyard piggeries. Multivariable logistic regression was performed to investigate associations between seropositivity and risk factors. Using the multivariable models, seroprevalence at geographic locations was predicted based on environmental variables. Goodness of fit of models was measured using area under the curve of the receiver operating characteristic, and the percentage of cases correctly classified as seropositive. Environmental predictors of seroprevalence included living below median altitude of a village, in agricultural areas, on clay soil, and higher density of piggeries above the house. Models had acceptable goodness of fit, and correctly classified ∼84% of cases.

Conclusions and Significance

Environmental variables could be used to identify high-risk areas for leptospirosis. Environmental monitoring could potentially be a valuable strategy for leptospirosis control, and allow us to move from disease surveillance to environmental health hazard surveillance as a more cost-effective tool for directing public health interventions.

Author Summary

Leptospirosis is the most common bacterial infection transmitted from animals to humans. Infected animals excrete the bacteria in their urine, and humans can become infected through contact with animals or a contaminated environment such as water and soil. Environmental factors are important in determining the risk of human infection, and differ between ecological settings. The wide range of risk factors include high rainfall and flooding; poor sanitation and hygiene; urbanisation and overcrowding; contact with animals (including rodents, livestock, pets, and wildlife); outdoor recreation and ecotourism; and environmental degradation. Predictive risk maps have been produced for many infectious diseases to identify high-risk areas for transmission and guide allocation of public health resources. Maps are particularly useful where disease surveillance and epidemiological data are poor. The objectives of this study were to estimate leptospirosis seroprevalence at geographic locations based on environmental factors, produce a predictive disease risk map for American Samoa, and assess the accuracy of the maps in predicting infection risk. This study demonstrated the value of geographic information systems and disease mapping for identifying environmental risk factors for leptospirosis, and enhancing our understanding of disease transmission. Similar principles could be used to investigate the epidemiology of leptospirosis in other areas.

Background

Leptospirosis has recently been discussed as an emerging infectious disease in many contexts, including changes in environmental drivers of disease transmission and the emergence of serovars. In this paper, we report the epidemiology of leptospiral serovars from our study of human leptospirosis in American Samoa in 2010, present evidence of recent serovar emergence, and discuss the potential epidemiological and ecological implications of our findings.

Methods

Serovar epidemiology from our leptospirosis seroprevalence study in 2010 was compared to findings from a study in 2004. The variation in geographic distribution of the three most common serovars was explored by mapping sero-positive participants to their place of residence using geographic information systems. The relationship between serovar distribution and ecological zones was examined using geo-referenced data on vegetation type and population distribution.

Results

Human leptospirosis seroprevalence in American Samoa was 15.5% in 2010, with serological evidence that infection was caused by three predominant serovars (Hebdomadis, LT 751, and LT 1163). These serovars differed from those identified in an earlier study in 2004, and were not previously known to occur in American Samoa. In 2010, serovars also differed in geographic distribution, with variations in seroprevalence between islands and different ecological zones within the main island.

Conclusions

Our findings might indicate artefactual emergence (where serovars were long established but previously undetected), but we believe the evidence is more in favour of true emergence (a result of ecological change). Possibilities include changes in interactions between humans and the environment; introduction of serovars through transport of animals; evolution in distribution and/or abundance of animal reservoirs; and environmental changes that favour transmission of particular serovars.

Future research should explore the impact of ecological change on leptospirosis transmission dynamics and serovar emergence, and investigate how such new knowledge might better target environmental monitoring for disease control at a public health level.

There has never been a locally transmitted outbreak of mosquito-borne disease in New Zealand, but the risk of an outbreak occurring is increasing with on-going interceptions of exotic mosquito vectors across its border, increasing traffic of goods and passengers, higher numbers of viremic travelers arriving, and local, regional, and global environmental change. The risk posed to New Zealand by chikungunya virus is potentially high because of the transmissibility of this virus in subtropical climates, compounded by a population that is predominantly immunologically naive to exotic arboviruses. However, risk reduction in New Zealand should not be considered in isolation but must be viewed within a wider South Pacific context. In this report, we discuss the potential threat posed by chikungunya to the region, focusing in particular on New Zealand, and re-emphasizing the need for a South Pacific–wide approach towards mosquito-borne disease prevention.

Surveys over 20 years have documented worsening in the dental health of preschoolers. Healthy People 2010 Midcourse Review reports the country moving away from oral health goals for young children; the slip is 57%. Exacerbating this is the inability of Medicaid to provide for those in need. Most children receive examinations only: few receive comprehensive care. We urge Head Start grantees to adopt a new approach to oral health goals and in this paper offer: (1) a review of the problem and premises preventing a solution; (2) a proposal that Head Start adopt a public health perspective; and (3) specific roles staff and dental personnel can take to mount aggressive strategies to arrest tooth decay at the grantee site.

The role climate change may play in altering human health, particularly in the emergence and spread of diseases, is an evolving area of research. It is important to understand this relationship because it will compound the already significant burden of diseases on national economies and public health. Authorities need to be able to assess, anticipate, and monitor human health vulnerability to climate change, in order to plan for, or implement action to avoid these eventualities. Environmental health indicators (EHIs) provide a tool to assess, monitor, and quantify human health vulnerability, to aid in the design and targeting of interventions, and measure the effectiveness of climate change adaptation and mitigation activities. Our aim was to identify the most suitable framework for developing EHIs to measure and monitor the impacts of climate change on human health and inform the development of interventions. Using published literature we reviewed the attributes of 11 frameworks. We identified the Driving force-Pressure-State-Exposure-Effect-Action (DPSEEA) framework as the most suitable one for developing EHIs for climate change and health. We propose the use of EHIs as a valuable tool to assess, quantify, and monitor human health vulnerability, design and target interventions, and measure the effectiveness of climate change adaptation and mitigation activities. In this paper, we lay the groundwork for the future development of EHIs as a multidisciplinary approach to link existing environmental and epidemiological data and networks. Analysis of such data will contribute to an enhanced understanding of the relationship between climate change and human health.

Background

This study had two principal objectives: (i) to investigate the relationship between asthma severity and proximity to major roadways in Perth, Western Australia; (ii) to demonstrate a more accurate method of exposure assessment for traffic pollutants using an innovative GIS-based measure that fully integrates all traffic densities around subject residences.

Methods

We conducted a spatial case-control study, in which 'cases' were defined as individuals aged under 19 years of age with more severe asthma (defined here as two or more emergency department contacts with asthma in a defined 5-year period) versus age- and gender-matched 'controls' with less severe asthma (defined here as one emergency department contact for asthma). Traffic exposures were measured using a GIS-based approach to determine the lengths of the roads falling within a buffer area, and then multiplying them by their respective traffic counts.

Results

We examined the spatial relationship between emergency department contacts for asthma at three different buffer sizes: 50 metres, 100 metres and 150 metres. No effect was noted for the 50 metre buffer (OR = 1.07; 95% CI: 0.91-1.26), but elevated odds ratios were observed with for crude (unadjusted) estimates OR = 1.21 (95% CI: 1.00-1.46) for 100 metre buffers and OR = 1.25 (95% CI: 1.02-1.54) for 150 metre buffers. For adjusted risk estimates, only the 150 metre buffer yielded a statistically significant finding (OR = 1.24; 95% CI:1.00-1.52).

Conclusions

Our study revealed a significant 24% increase in the risk of experiencing multiple emergency department contacts for asthma for every log-unit of traffic exposure. This study provides support for the hypothesis that traffic related air pollution increases the frequency of health service contacts for asthma. This study used advanced GIS techniques to establish traffic-weighted buffer zones around the geocoded residential location of subjects to provide an accurate assessment of exposure to traffic emissions, thereby providing a quantification of the ranges over which pollutants may exert a health effect.

In a world of emerging and resurging infectious diseases, dominated by zoonoses, environmental monitoring plays a vital role in our understanding their dynamics and their spillover to humans. Here, we critically review the ecology, epidemiology and need for monitoring of a variety of directly transmitted (Sin Nombre virus, Avian Influenza) and vector-borne (Ross River virus, West Nile virus, Lyme disease, anaplasmosis and babesiosis) zoonoses. We focus on the valuable role that existing monitoring plays in the understanding of these zoonoses, the demands for new monitoring, and how improvements can be made to existing monitoring. We also identify the fruitful outcomes which would result from implementation of the monitoring demands we have highlighted. This review aims to promote improvements in our understanding of zoonoses, their management, and public health by encouraging discussion among researchers and public health officials.

Background

Emerging environmental pressures resulting from climate change and globalization challenge the capacity of health information systems (HIS) in the Pacific to inform future policy and public health interventions. Ciguatera, a globally common marine food-borne illness, is used here to illustrate specific HIS challenges in the Pacific and how these might be overcome proactively to meet the changing surveillance needs resulting from environmental change.

Objectives

We review and highlight inefficiencies in the reactive nature of existing HIS in the Pacific to collect, collate, and communicate ciguatera fish poisoning data currently used to inform public health intervention. Further, we review the capacity of existing HIS to respond to new data needs associated with shifts in ciguatera disease burden likely to result from coral reef habitat disruption.

Discussion

Improved knowledge on the ecological drivers of ciguatera prevalence at local and regional levels is needed, combined with enhanced surveillance techniques and data management systems, to capture environmental drivers as well as health outcomes data.

Conclusions

The capacity of public HIS to detect and prevent future outbreaks is largely dependent on the future development of governance strategies that promote proactive surveillance and health action. Accordingly, we present an innovative framework from which to stimulate scientific debate on how this might be achieved by using existing larger scale data sets and multidisciplinary collaborations.

Background

The Transtheoretical Model suggests that individuals vary according to their readiness to change behavior. Previous work in smoking cessation and other health areas suggests that interventions are more successful when they are tailored to an individual's stage of change with regards to the specific behavior. We report on the performance of a single-item measure ("Ladder") to assess the readiness to change dental-avoidant behavior.

Methods

An existing Contemplation Ladder for assessing stage of change in smoking cessation was modified to assess readiness to go to a dentist. The resulting Ladder was administered to samples of English-speaking adolescents (USA), Spanish-speaking adults (USA), and Norwegian military recruits (Norway) in order to assess construct validity. The Ladder was also administered to a sample of English-speaking avoidant adolescents and young adults who were enrolled in an intervention study (USA) in order to assess criterion validity. All participants also had dental examinations, and completed other questionnaires. Correlations, chi square, t tests and one-way ANOVAs were used to assess relationships between variables.

Results

In two samples, participants who do not go to the dentist had significantly more teeth with caries; in a third sample, participants who do not go to the dentist had significantly worse caries. Ladder scores were not significantly related to age, gender, caries, or dental fear. However, Ladder scores were significantly related to statements of intention to visit a dentist in the future and the importance of oral health. In a preliminary finding, Ladder scores at baseline also predicted whether or not the participants decided to go to a dentist in the intervention sample.

Conclusions

The data provide support for the convergent and divergent construct validity of the Ladder, and preliminary support for its criterion validity. The lack of relationship between dental fear and Ladder scores suggests that avoidant individuals may be helped to decide to go to a dentist using interventions which do not explicitly target their fear.

Purpose

Dental services during pregnancy can improve maternal oral health, reduce mother-child transmission of cariogenic bacteria, and create opportunities for anticipatory guidance. This study aimed to understand why low-income women did or did not utilize dental services in a pilot program to promote dental visits during pregnancy in Klamath County, Oregon.

Methods

Sixty women were contacted and 51 participated in semi-structured telephone interviews regarding utilization of dental services during pregnancy. Women were selected randomly from the pilot program: 45 women (88%) utilized dental services and six did not. Transcripts were content analyzed using a mixed method qualitative approach - grounded theory and Stages of Change model - to identify themes and sub-themes.

Results

Most women overcame stress or dentally-related barriers to use care. Stressors included poor domestic relationships, personal finances, and employment. Dentally-related factors included perception of dental experience, attitude toward dental providers, importance/valuing of oral health, perceived ability to pay for care, time constraints, dental providers’ and office staff attitudes toward clients.

Conclusions

Identifying barriers that prevent low-income women from taking action to access dental care during pregnancy provides information essential for enhancing public-private health programs to promote dental visits, reduce mother-child transmission, and provide guidance to new mothers.

Background

Hispanics comprise the largest ethnic minority group in the United States. Previous work with the Spanish Modified Dental Anxiety Scale (MDAS) yielded good validity, but lower test-retest reliability. We report the performance of the Spanish MDAS in a new sample, as well as the performance of the Spanish Revised Dental Beliefs Survey (R-DBS).

Methods

One hundred sixty two Spanish-speaking adults attending Spanish-language church services or an Hispanic cultural festival completed questionnaires containing the Spanish MDAS, Spanish R-DBS, and dental attendance questions, and underwent a brief oral examination. Church attendees completed the questionnaire a second time, for test-retest purposes.

Results

The Spanish MDAS and R-DBS were completed by 156 and 136 adults, respectively. The test-retest reliability of the Spanish MDAS was 0.83 (95% CI = 0.60-0.92). The internal reliability of the Spanish R-DBS was 0.96 (95% CI = 0.94-0.97), and the test-retest reliability was 0.86 (95% CI = 0.64-0.94). The two measures were significantly correlated (Spearman's rho = 0.38, p < 0.001). Participants who do not currently go to a dentist had significantly higher MDAS scores (t = 3.40, df = 106, p = 0.003) as well as significantly higher R-DBS scores (t = 2.21, df = 131, p = 0.029). Participants whose most recent dental visit was for pain or a problem, rather than for a check-up, scored significantly higher on both the MDAS (t = 3.00, df = 106, p = 0.003) and the R-DBS (t = 2.85, df = 92, p = 0.005). Those with high dental fear (MDAS score 19 or greater) were significantly more likely to have severe caries (Chi square = 6.644, df = 2, p = 0.036). Higher scores on the R-DBS were significantly related to having more missing teeth (Spearman's rho = 0.23, p = 0.009).

Conclusion

In this sample, the test-retest reliability of the Spanish MDAS was higher. The significant relationships between dental attendance and questionnaire scores, as well as the difference in caries severity seen in those with high fear, add to the evidence of this scale's construct validity in Hispanic samples. Our results also provide evidence for the internal and test-retest reliabilities, as well as the construct validity, of the Spanish R-DBS.

Sequential 31P and 1H MRS was used to measure cerebral phosphate metabolites, intracellular pH, and lactate in normoglycemic and hypoglycemic rats during 30 min of complete cerebral ischemia and 5.5 h of reperfusion. These results were correlated with brain levels of free fatty acids (FFAs), excitatory amino acids, cations, and water content at death. The lactate/N-acetyl aspartate ratio was not significantly different between groups before or during occlusion. During reperfusion, the ratio was higher in normoglycemic rats from 3 to 85 min (p≤ 0.05), and recovery time was faster in hypoglycemic rats (29 vs 45 min; p = 0.04), suggesting reduced lactate production and faster recovery of aerobic metabolism. During occlusion, significant but comparable decrease of intracellular pH occurred in each group. Intracellular pH was higher in hypoglycemic rats at 140 min and 260 min of reperfusion. Water content, Na and K+ concentrations, and FFA and excitatory amino acid levels were not significantly different between groups, but hypoglycemic rats had less depletion of levels of Mg2+ (p=0.011). These results show that hypoglycemia has a limited but potentially beneficial effect on postischemic lactic acidosis.

To determine the relationship between reductions in the apparent diffusion coefficient of water (ADC) and in cerebral blood flow (CBF) during focal ischemia, we used diffusion-weighted magnetic resonance (D-MR) imaging and autoradiographic CBF analysis to examine rats subjected to 30 or 90 min of permanent middle cerebral artery (MCA) occlusion. In the 30-min occlusion group (n = l0), the area with substantially reduced ADC (15% or more below the contralateral level [ADCJ15]) corresponded best to the area with CBF below 25 ml/lOO g/min and was significantly smaller than the area with CBF below 50 m1/100 g/min (CBF50), a level associated with reduced protein synthesis and delayed necrosis (40 ± 13% versus 74 ± 8% of the ischemic hemisphere; P < 0.OOOl). In the 90-min occlusion group (n = 6), the ADC15 area corresponded best to the CBF30 to CBF35 area and was again significantly smaller than the CBF50 area (54 ± 13% versus 73 ± 20%, P < 0.05). Thus, the area of substantially reduced ADC at 30 and 90 min represents only 53% and 74%, respectively, of the tissue at risk for infarction. These findings indicate a potential limitation in using early D-MR imaging to predict stroke outcome.

The goal of these experiments was to test the hypothesis that in an animal model of temporal lobe epilepsy (TLE), magnetic resonance spectroscopic measurement of N-acetylaspartate (NAA) and other metabolites, together with magnetic resonance imaging, provides a sensitive in vivo method to localize and monitor the progression of neuronal cell death and gliosis. Seizures were induced in rats by unilateral hippocampal injection of kainate. Magnetic resonance measurements were made from 1 to 84 days using proton spectroscopic imaging (1H-MRSI), T2-weighted imaging (T2WI) and diffusion-weighted imaging (DWI). The results were compared with findings on histological sections. Decreased NAA and creatine levels and increased apparent diffusion coefficient of water were found in the ipsilateral hippocampus after 14 days where neuronal loss and gliosis were observed. In the contralateral hippocampus a significant increase of choline level was observed. These results suggest that 1H-MRSI is a useful in vivo method for localizing neuronal loss and may also indicate additional pathological and metabolic alterations. In addition, DWI may be a useful method for in vivo detection of tissue alterations due to TLE.

The growing scarcity of potable water supplies is among the most important issues facing many cities, in particular those using single sources of water that are climate dependent. Consequently, urban centers are looking to alternative sources of water supply that can supplement variable rainfall and meet the demands of population growth. A diversified portfolio of water sources is required to ensure public health, as well as social, economical and environmental sustainability. One of the options considered is the augmentation of drinking water supplies with advanced treated recycled water. This paper aims to provide a state of the art review of water recycling for drinking purposes with emphasis on membrane treatment processes. An overview of significant indirect potable reuse projects is presented followed by a description of the epidemiological and toxicological studies evaluating any potential human health impacts. Finally, a summary of key operational measures to protect human health and the areas that require further research are discussed.

Background

Dental neglect has been found to be related to poor oral health, a tendency not to have had routine check-ups, and a longer period of time since the last dental appointment in samples of children and adults. The Dental Neglect Scale (DNS) has been found to be a valid measure of dental neglect in samples of children and adults, and may be valid for adolescents as well. We administered the DNS to a sample of adolescents and report on the relationships between the DNS and oral health status, whether or not the adolescent has been to the dentist recently for routine check-ups, and whether or not the adolescent currently goes to a dentist. We also report the internal and test-retest reliabilities of the DNS in this sample, as well as the results of an exploratory factor analysis.

Methods

One hundred seventeen adolescents from seven youth groups in the Seattle-Tacoma metropolitan area (Washington State, U.S.) completed the DNS and indicated whether they currently go to a dentist, while parents indicated whether the adolescent had a check-up in the previous three years. Adolescents also received a dental screening. Sixty six adolescents completed the questionnaire twice. T-tests were used to compare DNS scores of adolescents who have visible caries or not, adolescents who have had a check-up in the past three years or not, and adolescents who currently go to a dentist or not. Internal reliability was measured by Cronbach's alpha, and test-rest reliability was measured by intra-class correlation. Factor analysis (Varimax rotation) was used to examine the factor structure.

Results

In each comparison, significantly higher DNS scores were observed in adolescents with visible caries, who have not had a check-up in the past three years, or who do not go to a dentist (all p values < 0.05). The test-retest reliability of the DNS was high (ICC = 0.81), and its internal reliability was acceptable (Cronbach's alpha = 0.60). Factor analysis yielded two factors, characterized by home care and visiting a dentist.

Conclusion

The DNS appears to operate similarly in this sample of adolescents as it has in other samples of children and adults.

Objective

This paper describes a community-based intervention to provide a dental home for women covered by Medicaid in Klamath County, Oregon. In 2001, 8.8% of pregnant women served by Medicaid in Oregon received care.

Methods

Pregnant women received home/WIC visits and were assigned a dental home under a dental managed care program (DCO). All initial care was provided at the Oregon Institute of Technology Dental Hygiene Clinic under the contract with the DCO. Emergency, preventive and restorative care was provided.

Result

Between February 2004 and January 2006, 503 pregnant women were identified: 421 women were contactable. Of these, 339 received home visits (339/421, 80.5%) and 235 received care (235/339, 69.3%). Overall, 55.8% of eligible women received care (235/421). Most who did not have a visit either moved or were not the caretaker of the baby. The missed appointment rate was 9%.

Conclusion

A community health partnership led to a successful and sustainable model extending care to pregnant women.

Background

By international standards, water supplies in Perth, Western Australia, contain high trihalomethane (THM) levels, particularly the brominated forms. Geographic variability in these levels provided an opportunity to examine cross-city spatial relationships between THM exposure and rates of birth defects (BDs).

Objectives

Our goal was to examine BD rates by exposure to THMs with a highly brominated fraction in metropolitan locations in Perth, Western Australia.

Methods

We collected water samples from 47 separate locations and analyzed them for total and individual THM concentrations (micrograms per liter), including separation into brominated forms. We classified collection areas by total THM (TTHM) concentration: low (< 60 μg/L), medium (> 60 to < 130 μg/L), and high (≥ 130 μg/L). We also obtained deidentified registry-based data on total births and BDs (2000–2004 inclusive) from post codes corresponding to water sample collection sites and used binomial logistic regression to compare the frequency of BDs aggregately and separately for the TTHM exposure groups, adjusting for maternal age and socioeconomic status.

Results

Total THMs ranged from 36 to 190 μg/L. A high proportion of the THMs were brominated (on average, 92%). Women living in high-TTHM areas showed an increased risk of any BD [odds ratio (OR) = 1.22; 95% confidence interval (CI), 1.01–1.48] and for the major category of any cardiovascular BD (OR = 1.62; 95% CI, 1.04–2.51), compared with women living in low-TTHM areas.

Conclusions

Brominated forms constituted the significant fraction of THMs in all areas. Small but statistically significant increases in risks of BDs were associated with residence in areas with high THMs.

New research developments frequently are neither adopted by providers nor utilized by patients. This dual problem of impacting the behaviors of providers and patients presents a challenge. This paper will present behavioral theories and technologies that can be utilized to impact both provider and patient behaviors.

Human health often depends on environmental variables and is generally subject to widespread and comprehensive surveillance. Compared with other available measures of ecosystem health, human disease incidence may be one of the most useful and practical bioindicators for the often elusive gauge of ecologic well-being. We argue that many subtle ecosystem disruptions are often identified only as a result of detailed epidemiologic investigations after an anomalous increase in human disease incidence detected by routine surveillance mechanisms. Incidence rates for vector-mediated diseases (e.g., arboviral illnesses) and direct zoonoses (e.g., hantaviruses) are particularly appropriate as bioindicators to identify underlying ecosystem disturbances. Outbreak data not only have the potential to act as a pivotal warning system for ecosystem disruption, but may also be used to identify interventions for the preservation of ecologic health. With this approach, appropriate ecologically based strategies for remediation can be introduced at an earlier stage than would be possible based solely on environmental monitoring, thereby reducing the level of “ecosystem distress” as well as resultant disease burden in humans. This concept is discussed using local, regional, and global examples, thereby introducing the concept of multilevel ecosystem interventions.

Converging themes from the fields of environmental health, ecology and health, and human ecology highlight opportunities for innovation and advancement in environmental health theory and practice. In this commentary we outline the role of research and applied programs that integrate biophysical and social sciences with environmental health practice in order to address deficiencies in each field when taken on its own. New opportunities for environmental health protection and promotion are outlined based on the three converging themes: integrated approaches to research and policy, methodological acknowledgment of the synergies between the social and biophysical environments, and incorporation of core ecosystem principles into research and practice. These converging themes are discussed in relation to their implications for new types of intervention to achieve health gains across different spatial and temporal scales at the interface between biophysical and social environments.