Watershed, climate, and stable isotope data (oxygen-18 and deuterium) for 50 boreal lakes in the oil sands region, northeastern Alberta, Canada, 2002-2017

Watershed data, climate and stable data collected over a 16-year period from a network of 50 lakes in northeastern Alberta, are provided to allow for broader incorporation into regional assessments of environmental impacts, particularly hydrologic and geochemical processes under changing climate and land use development. Oxygen-18 and deuterium analyses of water samples are provided from late summer surveys of 50 lakes with varying land cover and permafrost conditions. Six sub-groups of lakes are represented, including Stony Mountains, West Fort McMurray, Northeast Fort McMurray, Birch Mountains, Caribou Mountains and Shield. This dataset includes 1582 isotopic analyses made on 791 water samples and 3164 isotope mass balance model outputs, as well as 800 lake/watershed parameters, 5600 climate parameters, and 800 modelled values for isotopic composition of precipitation used in the computations. Model data are provided to facilitate evaluation of transferability of the model for other applications, and to permit more sophisticated spatial analysis and intercomparison with geochemical and biological datasets. Details and further discussion on the isotope mass balance approach are provided in “Regional trends in water balance and runoff to fifty boreal lakes: a 16-year isotope mass balance assessment including evaluation of hydrologic drivers” [1]. Overall, the data are expected to be useful, in comparison with local and regional datasets, for water resource management and planning, including design of monitoring networks and environmental impact assessments for oil sands projects.

Using stable isotopes paired with tritium analysis to assess thermokarst lake water balances in the Source Area of the Yellow River, northeastern Qinghai-Tibet Plateau, China

A spatially distributed network of thermokarst lakes undergoing significant environmental changes was sampled in 2014 and 2016 to develop a comprehensive understanding of lake water balances in lakes across a gradient of frozen ground conditions. Frozen ground ranges from seasonally frozen ground (SFG) to sporadic discontinuous permafrost (SDP) to extensive discontinuous permafrost (EDP), and is representative of complex conditions in the Source Area of the Yellow River, northeastern part of Qinghai-Tibet Plateau. Radioactive and stable water isotopes in reference lakes (non-thaw lakes), thermokarst lakes, precipitation, wetlands, ground ice and supra-permafrost groundwater are analyzed to characterize systematic variations and to assess lake water balances using stable isotope mass balance (IMB). IMB, paired with analysis of tritium decay gradients, is shown to be a valid approach for detecting short-term shifts in lake water balance, which allows evaluation of the proportion of precipitation-derived versus permafrost-derived water inputs to lakes. All lakes except EDP thaw lakes are evaporation-dominated (E/I > 0.5). Negative water balances occurred most frequently in reference lakes due to hydrological connectivity with rivers. Precipitation-derived water inputs result in positive water balances in SFG and SDP thermokarst lakes, but negative-trending water balances are found in SDP thermokarst lakes due to substantial reduction in water yield. Increasing contributions from thawing permafrost in EDP thermokarst lakes result in strong positive water balance. Permafrost degradation may also lead to the changes in hydrological connectivity between precipitation and wetlands or thermokarst lakes. Based on these findings, a conceptual model of the hydrological evolution of thermokarst lakes under the influence of permafrost degradation is proposed.

Stable isotope data (oxygen-18 and deuterium) from surveys of lakes, wetlands, rivers, and input waters across the South Athabasca Oil Sands region, Alberta, 2007-2009

Oxygen-18 and deuterium analyses of water samples are provided from a regional survey of lakes, wetlands, soil waters, groundwaters, and snowpack samples collected in the Southern Athabasca Oil Sands (SAOS) region, Alberta, Canada, mainly during 2007–2009. Lake, wetland, and river sampling were conducted by helicopter during late summer, capturing conditions close to peak evaporative enrichment. Shallow soil water from the unsaturated zone was also collected in late summer, whereas deeper groundwaters from Quaternary aquifers, Quaternary channels, and uppermost Cretaceous strata, were collected primarily as part of winter drilling programs by industrial partners. Snowpack samples were collected in late March/early April, prior to significant spring melt. This dataset includes 1576 isotopic analyses made on 788 water samples as well as selected isotope mass balance model outputs (lake evaporation/inflow and water yield to lakes). These basic model data are provided to facilitate evaluation of the method as a tool for spatial mapping of water yield and its interannual variability. Details and further discussion on the isotope mass balance approach are provided in “Mapping water yield distribution across the southern Athabasca Oil Sands area: baseline surveys applying isotope mass balance of lakes” (Gibson et al., 2019). Overall, the data are expected to be useful, in comparison with local and regional datasets, for water resource management and planning, including design of monitoring networks and environmental impact assessments for oil sands projects.

Cholera Mortality during Urban Epidemic, Dar es Salaam, Tanzania, August 16, 2015-January 16, 20161

In 2015, a cholera epidemic occurred in Tanzania; most cases and deaths occurred in Dar es Salaam early in the outbreak. We evaluated cholera mortality through passive surveillance, burial permits, and interviews conducted with decedents’ caretakers. Active case finding identified 101 suspected cholera deaths. Routine surveillance had captured only 48 (48%) of all cholera deaths, and burial permit assessments captured the remainder. We interviewed caregivers of 56 decedents to assess cholera management behaviors. Of 51 decedents receiving home care, 5 (10%) used oral rehydration solution after becoming ill. Caregivers reported that 51 (93%) of 55 decedents with known time of death sought care before death; 16 (29%) of 55 delayed seeking care for >6 h. Of the 33 (59%) community decedents, 20 (61%) were said to have been discharged from a health facility before death. Appropriate and early management of cholera cases can reduce the number of cholera deaths.

Use of TaqMan Array Cards to Screen Outbreak Specimens for Causes of Febrile Illness in Tanzania

We describe the deployment of a custom-designed molecular diagnostic TaqMan Array Card (TAC) to screen for 31 bacterial, protozoal, and viral etiologies in blood from outbreaks of acute febrile illness in Tanzania during 2015-2017. On outbreaks notified to the Tanzanian Ministry of Health, epidemiologists were dispatched and specimens were collected, transported to a central national laboratory, and tested by TAC within 2 days. This algorithm streamlined investigation, diagnosed a typhoid outbreak, and excluded dozens of other etiologies. This method is usable in-country and may be incorporated into algorithms for diagnosing outbreaks.

An After-effect in Haptic Space Perception

After-effects in haptic perception have been little studied. But they seem to be prominent, and easy to elicit. An after-effect of the perception of the vergence of two surfaces is described, and is shown to be independent of the slant of the surfaces. It is not “figural.” Spatial perception with the hands, as well as with the eyes, is apparently based on a fluid and adaptable receptive system.

Characterizing the PAHs in surface waters and snow in the Athabasca region: Implications for identifying hydrological pathways of atmospheric deposition

The composition of polycyclic aromatic hydrocarbons present in snow and surface waters in the Athabasca Oil Sands Region (AOSR) was characterized in order to identify major contributors to the organics detected in rivers and lakes in the region. PAH concentrations, measured by three monitoring programs in 2011, were used to compare the PAH compositions of snow and surface waters across the AOSR. The 2011 dataset includes total (dissolved+particulate) concentrations of thirty-four parent and alkylated PAH compounds in 105 snow, 272 river, and 3 lake samples. The concentration of PAHs in rivers varies seasonally, with the highest values observed in July. The timing of increases in PAH concentrations in rivers coincides with the high river discharge during the spring freshet, indicating that this major hydrological event may play an important role in delivering PAHs to rivers. However, the composition of PAHs present in rivers during this period differs from the composition of PAHs present in snow, suggesting that direct runoff and release of PAHs accumulated on snow may not be the major source of PAHs to the Athabasca River and its tributaries. Instead, snowmelt may contribute indirectly to increases in PAHs due to hydrological processes such as erosion of stream channels, remobilization of PAH-containing sediments, increased catchment runoff, and snowmelt-induced groundwater inputs during this dynamic hydrologic period. Better understanding of transformations of PAH profiles during transport along surface and subsurface flow paths in wetland-dominated boreal catchments would improve identification of potential sources and pathways in the region. The compositional differences highlight the challenges in identifying the origins of PAHs in a region with multiple potential natural and anthropogenic sources particularly when the potential transport pathways include air, soil and water.

Suitability of selected free-gas and dissolved-gas sampling containers for carbon isotopic analysis

RATIONALE

Storage trials were conducted for 2 to 3 months using a hydrocarbon and carbon dioxide gas mixture with known carbon isotopic composition to simulate typical hold times for gas samples prior to isotopic analysis. A range of containers (both pierced and unpierced) was periodically sampled to test for δ(13)C isotopic fractionation.

METHODS

Seventeen containers were tested for free-gas storage (20°C, 1 atm pressure) and 7 containers were tested for dissolved-gas storage, the latter prepared by bubbling free gas through tap water until saturated (20°C, 1 atm) and then preserved to avoid biological activity by acidifying to pH 2 with phosphoric acid and stored in the dark at 5°C. Samples were extracted using valves or by piercing septa, and then introduced into an isotope ratio mass spectrometer for compound-specific δ(13)C measurements.

RESULTS

For free gas, stainless steel canisters and crimp-top glass serum bottles with butyl septa were most effective at preventing isotopic fractionation (pierced and unpierced), whereas silicone and PTFE-butyl septa allowed significant isotopic fractionation. FlexFoil and Tedlar bags were found to be effective only for storage of up to 1 month. For dissolved gas, crimp-top glass serum bottles with butyl septa were again effective, whereas silicone and PTFE-butyl were not. FlexFoil bags were reliable for up to 2 months.

CONCLUSIONS

Our results suggest a range of preferred containers as well as several that did not perform very well for isotopic analysis. Overall, the results help establish better QA/QC procedures to avoid isotopic fractionation when storing environmental gas samples. Recommended containers for air transportation include steel canisters and glass serum bottles with butyl septa (pierced and unpierced).

Characterization of organic composition in snow and surface waters in the Athabasca Oil Sands Region, using ultrahigh resolution Fourier transform mass spectrometry

This study was conducted to characterize the composition of dissolved organic compounds present in snow and surface waters in the Athabasca Oil Sands Region (AOSR) with the goal of identifying whether atmospherically-derived organic compounds present in snow are a significant contributor to the compounds detected in surface waters (i.e., rivers and lakes). We used electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI-FTICR MS) to characterize the dissolved organic compound compositions of snow and surface water samples. The organic profiles obtained for the snow samples show compositional differences between samples from near-field sites (<5 km from oil sands activities) and those from more distant locations (i.e., far-field sites). There are also significant compositional differences between samples collected in near-field sites and surface water samples in the AOSR. The composition of dissolved organic compounds at the upstream Athabasca River site (i.e., Athabasca River at Athabasca) is found to be different from samples obtained from downstream sites in the vicinity of oil sands operations (i.e., Athabasca River at Fort McMurray and Athabasca River at Firebag confluence). The upstream Athabasca River sites tended to share some compositional similarities with far-field snow deposition, while the downstream Athabasca River sites are more similar to local lakes and tributaries. This contrast likely indicates the relative role of regional snowmelt contributions to the Athabasca River vs inputs from local catchments in the reach downstream of Fort McMurray.

Respiratory symptoms and lung function 8-10 months after community exposure to chlorine gas: a public health intervention and cross-sectional analysis

Background

We implemented a community based interventional health screening for individuals located within one mile of a 54 metric tons release of liquid chlorine following a 16 tanker car train derailment on 6 January, 2005 in Graniteville, South Carolina, USA. Public health intervention occurred 8–10 months after the event, and provided pulmonary function and mental health assessment by primary care providers. Its purpose was to evaluate those exposed to chlorine for evidence of ongoing impairment for medical referral and treatment. We report comparative analysis between self-report of respiratory symptoms via questionnaire and quantitative spirometry results.

Methods

Health assessments were obtained through respiratory symptom and exposure questionnaires, simple spirometry, and physical exam. Simple spirometry was used as the standard to identify continued breathing problems. Sensitivity, specificity, positive and negative predictive values were applied to evaluate the validity of the respiratory questionnaire. We also identified the direction of discrepancy between self-reported respiratory symptoms and spirometry measures. Generalized estimation equations determined prevalence ratios for abnormal spirometry based on the presence of participant persistent respiratory symptoms. Covariate adjustment was made for participant age, sex, race, smoking and educational status.

Results

Two hundred fifty-nine people participated in the Graniteville health screening; 53 children (mean age = 11 years, range: <1-16), and 206 adults (mean age = 50 years, range: 18–89). Of these, 220 (85%) performed spirometry maneuvers of acceptable quality. Almost 67% (n = 147) displayed abnormal spirometry, while 50% (n = 110) reported persistent new-onset respiratory symptoms. Moreover, abnormal spirometry was seen in 65 participants (29%) who did not report any discernible breathing problems. This represented a net 16.8% underreporting of symptoms. Sensitivity and specificity of questionnaire self-report of symptoms were low at 55.8% and 61.6%, respectively. Persistent cough (41%) and shortness of breath (39%) were the most frequently reported respiratory symptoms.

Conclusion

Eight to ten months after acute chlorine exposure, the Graniteville health screening participants under-reported respiratory symptoms when compared to abnormal spirometry results. Sensitivity and specificity were low, and we determined that relying upon the self-report questionnaire was not adequate to objectively assess the lung health of our population following irritant gas exposure.

Repeat Western blot testing after receiving an HIV diagnosis and its association with engagement in care

OBJECTIVES

To examine the prevalence of and factors associated with potentially unnecessary repeat confirmatory testing after initial HIV diagnosis and the relationship of repeat testing to medical care engagement.

DESIGN

South Carolina HIV/AIDS surveillance data for 12,504 individuals who were newly diagnosed with HIV infection between January 1997 and December 2008 were used for this analysis. State law requires that all positive Western blot [WB] results be reported regardless of frequency.

METHODS

HIV-infected persons, diagnosed from 1997-2008 and followed through 2009, with repeat positive WB results were compared to those who did not have repeat positive WB results. We defined repeat positive testing as documentation of one or more positive WB obtained ≥90 days following initial WB confirmatory result. HIV care engagement for the period from 2007-2009 was assessed by documentation of CD4+ T-cell/viral load reports to the South Carolina HIV/AIDS surveillance system during each six-month period of a calendar year for those individuals diagnosed prior to the assessment period and still alive at the end. Relative risk [RR] with 95% confidence intervals [CI] and multivariable general linear models were used to assess if any covariates of interest were independently associated with repeat positive confirmatory testing.

RESULTS

A total of 4,237 [34%] of 12,504 HIV-infected individuals had results of repeat positive WB testing reported to the surveillance system during 1997-2008. Persons who had repeat positive WB testing were more likely than persons who did not have repeat WB testing to have progressed to AIDS >1 year following diagnosis [RR: 1.70; 95% CI: 1.61, 1.80] and to be consistently in care [RR: 1.35; 95% CI: 1.24, 1.47] or have sporadic care [RR: 1.80; 95% CI: 1.68, 1.94].

DISCUSSION

Having repeat positive WB tests may be a marker of engaging HIV care. However, given the limited resources available for care, it is important that healthcare reform policy and clinical recommendations promote improvements in communications about previous test results.

Delivering laboratory results by text message and e-mail: a survey of factors associated with conceptual acceptability among STD clinic attendees

OBJECTIVE

This study examines factors associated with the acceptability of receiving sexually transmitted disease (STD) laboratory results by text message and e-mail among clinic attendees.

SUBJECTS AND METHODS

An anonymous self-administered survey was conducted with a convenience sample of STD clinic attendees in South Carolina and Mississippi in 2009-2010. In total, 2,719 individuals with a median age of 26 years (interquartile range, 21-32 years) completed the survey.

RESULTS

More than 70% had Internet access at home, and 80% reported using text messaging daily. Participants preferred receiving laboratory results by text message compared with e-mail (50.2% versus 42.3%; p<0.001). Acceptability of receiving laboratory results by text message was higher with younger age (adjusted odds ratio [aOR] 1.13; 95% confidence interval [CI] 1.10-1.26), daily use of text messaging (aOR 1.30; 95% CI 1.14-1.49), and reporting cell phone and text message as the preferred choice of regular communication with the clinic (aOR 2.31; 95% CI 1.50-3.58) and was significantly lower in female subjects (aOR 0.89; 95% CI 0.81-0.98) and those with college-level education (aOR 0.88; 95% CI 0.77-0.99).

CONCLUSIONS

A majority of STD clinic attendees have access to cell phones and Internet. The acceptability of receiving STD laboratory results electronically may facilitate test result delivery to patients and expedite treatment of infected individuals.

HIV testing in women: missed opportunities

OBJECTIVE

To investigate opportunities for early human immunodeficiency virus (HIV) testing of women.

METHODS

A retrospective cohort study design linked case reports from HIV surveillance to several statewide health-care databases. Medical encounters occurring before the first positive HIV test (missed opportunities) were categorized by diagnosis/procedure codes to distinguish visits that were likely to have prompted an HIV test. Women were categorized as late testers (AIDS diagnosis <12 months from first HIV test date), non-late testers (no AIDS diagnosis during study period or diagnosis of AIDS >12 months of HIV diagnosis), of reproductive age (13-44 years old), and not of reproductive age (>44 years old). Adjusted odds ratios (aOR) and 95% confidence intervals (CI) were used to estimate risk and its statistical significance.

RESULTS

Of 3303 HIV-infected women diagnosed during the study period, 2408 (73%) had missed opportunity visits. Late testers (39%) were more likely to be black than white (aOR 1.48, 95% CI 1.12-1.95), be older (>44 years old; aOR 7.85, 95% CI 4.49-13.7), and have >10 missed opportunity visits (aOR 2.17, 95% CI 1.62-2.91). Fifty-four percent of women >44 years old were also late testers. Women >44 years old had lower median initial CD4 counts (p<0.001). The top two procedures were the same for all groups of women but mammography was ranked fourth for women >44 years old and Papanicolau smear was ranked fourth for late testers.

CONCLUSIONS

Feasibility and acceptability of routine HIV testing in nontraditional health-care settings, such as mammography and Papanicolau screenings, should be explored to identify late testers and older (not of reproductive age) HIV-infected women.

Follow-up assessment of health consequences after a chlorine release from a train derailment--Graniteville, SC, 2005

INTRODUCTION

After a train derailment released chlorine gas in Graniteville, South Carolina, in 2005, a multiagency team performed an epidemiologic assessment of chlorine exposure and resulting health effects. Five months later, participants were resurveyed to determine their health status and needs and to assist in planning additional interventions in the community.

METHODS

Questionnaires were mailed to 279 patients interviewed in the initial assessment; follow-up telephone calls were made to nonresponders. The questionnaire included questions regarding duration of symptoms experienced after exposure and a posttraumatic stress disorder (PTSD) assessment tool.

RESULTS

Ninety-four questionnaires were returned. Seventy-six persons reported chronic symptoms related to the chlorine exposure, 47 were still under a doctor's care, and 49 were still taking medication for chlorine-related problems. Agreement was poor between the first and second questionnaires regarding symptoms experienced after exposure to the chlorine (κ=0.30). Forty-four respondents screened positive for PTSD. PTSD was associated with post-exposure hospitalization for three or more nights [relative risk (RR) = 1.7; 95% confidence interval (CI)=1.1-2.6] and chronic symptoms (RR=9.1; 95% CI=1.3-61.2), but not with a moderate-to-extreme level of chlorine exposure (RR=1.2; 95% CI=0.8-1.8).

CONCLUSIONS

Some victims of this chlorine exposure event continued to experience physical symptoms and continued to require medical care 5 months later. Chronic mental health symptoms were prevalent, especially among persons experiencing the most severe or persistent physical health effects. Patients should be interviewed as soon as possible after an incident because recall of acute symptoms experienced can diminish within months.

The impact of retention in early HIV medical care on viro-immunological parameters and survival: a statewide study

Current literature on retention in HIV care fails to account for patients who continually/simultaneously access different providers. This statewide study examined retention in early HIV medical care and its impact on viro-immunological improvement and survival outcomes. It was a retrospective study of South Carolina residents ≥13 years old who were diagnosed with HIV infection in 2004-2007 and initially entered in care. CD4 count/percent and viral load (VL) tests that must be reported to the South Carolina HIV surveillance database were used as a proxy for a clinical visit. Retention was defined as at least one visit in each of four 6-month periods over 2 years postlinkage. Retention rates were categorized as "optimal" (visits in four intervals), "suboptimal" (visits in three intervals), sporadic (visits in two or one intervals), and "dropout" (no visits). Logistic regression and Cox proportional analyses were used to examine retention. Of the 2197 persons, about 50% failed to maintain optimal retention in care postlinkage. Male gender, nonwhite race/ethnicity, younger age, delayed linkage, and HIV-only status were significant predictors of lower rate of retention. Mean decrease in baseline log(10) VL was greater among those with optimal compared to suboptimal (-1.81 vs. -1.42; p < 0.001) and sporadic retention (-1.81 vs. -0.70; p < 0.001). Mean increase in baseline CD4 count was greater in optimal retention compared to suboptimal (169.70 vs. 107.5; p < 0.001) and sporadic retention (169.70 vs. 2.43; p < 0.001). Increased risk of mortality was associated with sporadic retention (aHR 2.91; 95% CI 1.54-5.50) and "dropout" (aHR 4.00; 95% CI 1.50-10.65). Rate of poor retention in early HIV medical care was relatively higher than reported in clinic-based data. Increasing the rate of retention in early HIV care could substantially improve viro-immunological parameters and survival outcomes.

Predictors of time to enter medical care after a new HIV diagnosis: a statewide population-based study

Public health benefits of expanded HIV screening will be adequately realized only if an early diagnosis is followed by prompt linkage to care. We characterized rates and factors associated with failure to enter into medical care within three months of HIV diagnosis and assessed the predictors of time to enter care over a follow-up period of up to 60 months. The study cohort included 3697 South Carolina (SC) residents' ≥13 years who were newly HIV-diagnosed in 2004-2008. Date of first laboratory report of CD4(+) T-cell count or viral load (VL) test after 30 days of confirmatory HIV diagnosis was used to define time to linkage to care. Results showed that of the total 3697 persons, 1768 (48%) entered care within three months, 1115 (30%) in four-12 months after diagnosis, and 814 (22%) failed to initiate care within 12 months of HIV diagnosis. At the end of study follow-up period of up to 60 months from the date of HIV diagnosis, 472/3697 (13%) individuals remained out of care. Multivariable Cox proportional hazards analysis showed that compared with hospitals, time to enter care was shorter in those diagnosed at state mental health/correctional facilities (adjusted hazards ratio [aHR] 1.16; 95% confidence interval [CI] 1.02-1.34) and longer in those diagnosed at county health departments (aHR 0.87; 95% CI 0.80-0.96) and at "Other/unknown" facilities (aHR 0.79; 95% CI 0.70-0.89). Time to entry into care was longer for men (aHR 0.82; 95% CI 0.75-0.89) compared with women, blacks (aHR 0.91; 95% CI 0.83-0.98) compared with whites, and males who have sex with males (MSM) (aHR 0.89; 95% CI 0.80-0.98) compared with heterosexual exposure. Delayed entry into HIV care remains a challenge in controlling HIV transmission in SC. Better integration of testing and care facilities could improve the proportion of newly HIV-diagnosed persons who enter care in a timely manner.

Associations of rural residence with timing of HIV diagnosis and stage of disease at diagnosis, South Carolina 2001-2005

CONTEXT

Rural areas in the southern United States face many challenges, including limited access to health care services and stigma, which may lead to later HIV diagnosis among rural residents.

PURPOSE

To investigate the associations of rural residence with timing of HIV diagnosis and stage of disease at diagnosis.

METHODS

Timing of HIV diagnosis was categorized as a diagnosis of acquired immune deficiency syndrome within 1 year of a first positive HIV test or HIV-only. Stage of disease was based on initial CD4+ T-cell count taken within 1 year of diagnosis. County of residence at HIV diagnosis was classified as urban if the population of the largest city was at least 25,000; it was classified as rural otherwise. Logistic regression was used to analyze timing of HIV diagnosis, and analysis of covariance was used to analyze stage of disease.

FINDINGS

From 2001 to 2005, 4,137 individuals were diagnosed with HIV infection. Of these, 1,129 (27%) were rural and 3,008 (73%) were urban residents. Among rural residents, 533 (47%) were diagnosed late, compared with 1,258 (42%) urban residents. Rural residents were significantly more likely to be diagnosed late (OR 1.19 [95% CI, 1.02-1.38]). Rural residence was associated with lower initial CD4+ T-cell count in crude analysis (P= .01) but not after adjustment (P > .05).

CONCLUSIONS

Rural residence is a risk factor for late HIV diagnosis. This may lead to reduced treatment response to antiretroviral medications, increased morbidity and mortality, and greater HIV transmission risks among rural residents. New testing strategies are needed that address challenges to HIV testing and diagnosis specific to rural areas.

GRACE: public health recovery methods following an environmental disaster

Different approaches are necessary when community-based participatory research (CBPR) of environmental illness is initiated after an environmental disaster within a community. Often such events are viewed as golden scientific opportunities to do epidemiological studies. However, the authors believe that in such circumstances, community engagement and empowerment needs to be integrated into the public health service efforts in order for both those and any science to be successful, with special care being taken to address the immediate health needs of the community first, rather than the pressing needs to answer important scientific questions. The authors will demonstrate how they have simultaneously provided valuable public health service, embedded generalizable scientific knowledge, and built a successful foundation for supplemental CBPR through their on-going recovery work after the chlorine gas disaster in Graniteville, South Carolina.

Missed opportunities for early HIV diagnosis in correctional facilities

To quantify the extent that South Carolina HIV/AIDS cases could have been diagnosed during a prior arrest we designed a retrospective population-based cohort study linking case reports from HIV/AIDS Reporting System (HARS) and the South Carolina Law Enforcement Division database. Data from individuals newly diagnosed between January 2001 and December 2005 were linked with statewide arrest records from April 1991 through November 2005. Criminal history data for this report were derived from 28 state prisons and more than 250 law enforcement agencies (jails, lockups, detention centers). Odds ratios and 95% confidence intervals were used to determine how demographic variables and arrest reasons affects receipt of HIV testing. There were 1961/4036 (48.6%) incident cases of HIV diagnosis that had at least one arrest prior to their first positive HIV test. When restricted to 1286/1961 (65.6%) individuals most likely to have been HIV-infected at the time of arrest, 592 (46%) were early testers (no AIDS within 1 year) and 694 (54%) developed AIDS more than 1 year of testing (late testers). After controlling for gender, age, race, behavioral risk and source of HIV report, the odds of being a late tester increased with age (p < 0.001). Overall, 3750 separate arrests were recorded for these 1286 individuals and 491 (13%) arrests were for drug and alcohol or sex crimes. Individuals with 4 or more arrests were more likely to be late testers when compared to those with fewer than 4 arrests (adjusted odds ratio [AOR] 3.30; 95% confidence [CI] 2.28, 4.72). Correctional facilities present considerable opportunities to identify individuals with undiagnosed HIV infection. Providing correctional facilities with the infrastructure for implementation of routine HIV testing would consequently have a significant impact on the health status of the entire community.

Reprinted from The British Journal of Psychology (1958), 49, 182-194: Visually controlled locomotion and visual orientation in animals

A general theory of locomotor behaviour in relation to physical objects is presented. Since the controlling stimulation for such behaviour is mainly optical, this involves novel assumptions about object perception and about what is called 'visual kinaesthesis'. Evidence for these assumptions is cited. On the basis of this theory it is possible to suppose that animals are visually oriented to the surfaces of their environment, not merely to light as such. In short, it is possible to explain why they seem to have space perception. Implications of this approach for maze-learning are pointed out.

Risk-based HIV testing in South Carolina health care settings failed to identify the majority of infected individuals

To provide evidence of large numbers of missed opportunities for early HIV diagnosis we designed a retrospective cohort study linking surveillance data from the South Carolina HIV/AIDS Reporting System to a statewide all payer health care database. We determined visits and diagnoses occurring before the date of the first positive HIV test and medical encounters were categorized to distinguish visits that were likely versus unlikely to have prompted an HIV test. Of the 4117 HIV-positive individuals newly diagnosed between 2001 and 2005, 3021 (73.4%) visited a South Carolina health care facility one or more times prior to testing HIV positive. Of these 3021, 1311 (43.4%) were late testers, and 1425 (47.2%) were early testers. Females were less likely than males to be late testers (odds ratio [OR] 0.55, 95% confidence interval [CI] 0.45-0.68), blacks were more likely than whites to be late testers (OR 1.37, 95% CI 1.10-1.71), and persons 50 years of age and older more likely to be late testers (OR 7.16, 95% CI 3.84-13.37). A total of 78.8% of the 13,448 health care visits for both late and early testers were for health care diagnoses unlikely to prompt an HIV test. These findings underscore the need for more routine HIV testing of adults and adolescents visiting health care facilities in order to facilitate early diagnosis.

A routine HIV screening program in a South Carolina community health center in an area of low HIV prevalence

In 2006, the Centers for Disease Control and Prevention published guidelines for routine HIV screening in healthcare settings. Feasibility studies have demonstrated that screening is effective in high-volume, urban settings, but there are no data for smaller, more rural settings. The main objective of this study was to describe a routine HIV screening program at a community health center in South Carolina serving both urban and rural populations. Margaret J. Weston Community Health Center implemented routine HIV screening using rapid tests at its three locations on December 1, 2006. All individuals utilizing this center over the age of 13 years were screened for HIV unless they opted out. Nurses completed a survey about their experiences with the program. chi(2) tests and logistic regression models were used to analyze the data. In the first 8 months, among 985 eligible visits, 574 (58%) resulted in the patient being screened. The most common reason for refusal was "doesn't think s/he is at risk." Acceptance rates differed significantly by location (p = 0.01), from 62% in the urban site to 47% in the rural site. Other significant predictors of accepting HIV testing were race/ethnicity, age, and method of payment. Three hundred twenty-four (58%) individuals who were tested reported no history of being previously tested for HIV infection. Participation in the screening program was perceived favorably by nurses. This pilot project in a South Carolina community health center demonstrates that implementation of routine HIV screening is acceptable in small healthcare settings and in smaller cities and rural communities in the South.

Rapid assessment of exposure to chlorine released from a train derailment and resulting health impact

OBJECTIVES

After a train derailment released approximately 60 tons of chlorine from a ruptured tanker car, a multiagency team performed a rapid assessment of the health impact to determine morbidity caused by the chlorine and evaluate the effect of this mass-casualty event on health-care facilities.

METHODS

A case was defined as death or illness related to chlorine exposure. Investigators gathered information on exposure, treatment received, and outcome through patient questionnaires and medical record review. An exposure severity rating was assigned to each patient based on description of exposure, distance from derailment, and duration of exposure. A case involving death or hospitalization > or = 3 nights was classified as a severe medical outcome. Logistic regression was used to examine factors associated with severe medical outcomes.

RESULTS

Nine people died, 72 were hospitalized in nine hospitals, and 525 were examined as outpatients. Fifty-one people (8%) had a severe medical outcome. Of 263 emergency department visits within 24 hours of the incident, 146 (56%) were in Augusta, Georgia; at least 95 patients arrived at facilities in privately owned vehicles. Patients with moderate-to-extreme exposure were more likely to experience a severe medical outcome (relative risk: 15.2; 95% confidence interval 4.8, 47.8) than those with a lower rating.

CONCLUSIONS

The rapid investigation revealed significant morbidity and mortality associated with an accidental release of chlorine gas. Key findings that should be addressed during facility, community, state, and regional mass-casualty planning include self-transport of symptomatic people for medical care and impact on health-care facilities over a wide geographic area.

Children with a TV in their bedroom at higher risk for being overweight

OBJECTIVE

We examined having a TV in the bedroom as a risk factor for child overweight.

DESIGN

Cross-sectional study.

SETTING

School- and telephone-based surveys in New Hampshire and Vermont between 2002 and 2004.

PARTICIPANTS

Two thousand three hundred and forty-three children enrolled in public schools, aged 9-12 years, and one of their parents.

MAIN EXPOSURES

The child having a TV in the bedroom.

MAIN OUTCOME MEASURES

Age- and gender-standardized child body mass index (zBMI). Overweight was defined as equal to or above the 95th percentile for zBMI.

RESULTS

Overall, 22.3% (N=523) of the children were overweight, and almost half of all children (48.2%, N=1130) had a TV in their bedroom. Children with a TV in their bedroom had a higher zBMI and were significantly more likely to be overweight compared to those without a TV in their bedroom (27.3 versus 17.7%, respectively; P<0.05). After controlling for sociodemographics, physical activity, frequency of TV or movie watching and internet use, children with a TV in their bedroom who watched at least one session of TV or movies per day were more likely to be overweight compared to those without a TV in their bedroom (odds ratio=1.32, 95% confidence interval: 1.03, 1.70).

CONCLUSIONS

Having a TV in the bedroom is a risk factor for child overweight, independent of reported physical activity, participation in team sports, TV or movie watching time and internet use at home. Further study is needed to fully understand the mechanism by which having a TV in the bedroom increases children's risk for overweight.

Climate change, flow regulation and land-use effects on the hydrology of the Peace-Athabasca-Slave System; findings from the Northern Rivers Ecosystem Initiative

The Northern Rivers Ecosystem Initiative (NREI) was established in the late 1990s to address important science questions resulting from previous studies undertaken by the Northern Rivers Basin Study (NRBS). This manuscript summarizes the results from a number of reports on hydrologic research conducted on the Peace-Athabasca-Slave river and lake systems. Specific concerns expressed by the NRBS and subsequent NREI focused on how these systems were being affected by climate change, flow regulation and land-use changes. Issues addressed in this report include: the fate of aquatic perched basins within the Peace-Athabasca Delta under historical and future climate trends; the sources of major floods that replenish these basins and how the frequency, magnitude and source areas of such events have changed over time; the synoptic weather patterns and atmospheric teleconnections that are responsible for the generation of major snowmelt runoff that drive major floods; the potential effect that climate and land-use changes might have on basin runoff and delta lake levels; the specific hydro-climatic conditions required to produce major ice-jam floods on the Peace River and how these may be altered by climate change; remote-sensing methods to document delta flooding and vegetation change; and the dual effect of climate and flow regulation on the water levels of Great Slave Lake and how these may affect other nearshore processes, particularly wind seiches, that influence flooding of the Slave River Delta. A review of the major findings and recommendations for future research concludes the report.

Wound oxygen levels during hyperbaric oxygen treatment in healing wounds

Hyperbaric oxygen (HBO2) increases wound oxygen delivery, but few data quantify wound oxygen levels over the course of healing. We characterized these changes during and after HBO2 treatment in a rat wound model. The treatment group (n=7) received 2.0 ATA HBO2, 90 minutes BID for 15 days. Control rats (n=5) were only exposed to HBO2 during measurement. On days 5, 10, and 15, wound pO2 was measured before, during, and for an hour after HBO2 treatment. Both the peak pO2 and the pO2 one hour after HBO2 treatment were significantly greater than baseline on all days in both the treatment (p < .01) and control group (p < .05). The peak pO2 during HBO2 exposure and one hour after decreased significantly in the treatment group on day 15 compared to day 5 (p <.01, p <.05 respectively). No significant differences were found in pO2 values between days within the control group. These results demonstrate that both the peak wound oxygen levels and duration of elevation change significantly throughout the course of HBO2 treatment.

A groundwater separation study in boreal wetland terrain: the WATFLOOD hydrological model compared with stable isotope tracers

Monitoring of stable water isotopes (18O and 2H) in precipitation and surface waters in the Mackenzie River basin of northern Canada has created new opportunities for researchers to study the complex hydrology and hydroclimatology of this remote region. A number of prior studies have used stable isotope data to investigate aspects of the hydrological regime of the wetland-dominated terrain near Fort Simpson, Northwest Territories, Canada. The present paper compares estimates of groundwater contributions to streamflow derived using the WATFLOOD distributed hydrological model, equipped with a new water isotope tracer module, with the results of conventional isotope hydrograph separation for five wetland-dominated catchments along the lower Liard River. The comparison reveals highly promising agreement, verifying that the hydrological model is simulating groundwater flow contributions to total streamflow with reasonable fidelity, especially during the crucial snowmelt period. Sensitivity analysis of the WATFLOOD simulations also reveals intriguing features about runoff generation from channelized fens, which may contribute less to streamflow than previously thought.

Laboratory Survey of Antibiotic Nonsusceptibility among Streptococcus pneumoniae Isolates in South Carolina, 1998 versus 2000

BACKGROUND

In 1998, the South Carolina Department of Health and Environmental Control surveyed clinical microbiology laboratories statewide to determine the prevalence of antibiotic nonsusceptibility among isolates of Streptococcus pneumoniae. A follow-up study was conducted in 2001.

METHODS

A cross-sectional study was conducted to estimate the prevalence of penicillin nonsusceptibility (PCN-N), extended-spectrum cephalosporin nonsusceptibility (ESC-N), and levofloxacin nonsusceptibility (LEV-N) in South Carolina. A standardized questionnaire was mailed to 89 laboratories.

RESULTS

The prevalence of penicillin intermediate resistance increased from 1998 (17.6%) to 2000 (20.9%, chi2 P = 0.008). Furthermore, the prevalence of PCN-N increased from 1998 (34.5%) to 2000 (38.4%, chi2 P = 0.01). The prevalence of ECN-N decreased from 1998 (19.1%) to 2000 (17.7%), but the difference was not significant (chi2 P = 0.25).

CONCLUSION

The laboratory survey was a low-cost method of estimating the change in prevalence of antibiotic nonsusceptibility, and it emphasizes regional surveillance because the prevalence of antibiotic nonsusceptibility varied geographically.

Prevalence monitoring in syphilis surveillance: results from a multicenter research program

BACKGROUND

Syphilis seroprevalence data can be used as an independent measure of syphilis trends and to augment syphilis case report data for program planning. The prevalence of reactive syphilis serology in jails, delivery rooms, and drug treatment centers was examined from 1995 to 1999. Prevalence was evaluated by age and gender at each site and compared with county primary and secondary syphilis case rates. Annual prevalence of high titer-reactive serology in jails was compared with primary and secondary syphilis case rates.

GOAL

The goal was to examine trends in syphilis seroprevalence and to evaluate the relationship of trends in seroprevalence to reported cases.

STUDY DESIGN

This was a cross-sectional survey.

RESULTS

Prevalence of reactive serology and high titer-reactive serology was lowest among women in delivery rooms (2.9% and 0.4%, respectively) and highest among women in jails (11.1% and 4.1%, respectively), indicating substantial recently treated or active infection among women in jails. Trends in high titer-reactive serology were similar to primary and secondary syphilis case rates.

CONCLUSION

The prevalence of high titer-reactive serology can provide valuable information about community syphilis morbidity for use in prevention and control programs.

Characteristics of persons with syphilis in areas of persisting syphilis in the United States: sustained transmission associated with concurrent partnerships

BACKGROUND AND GOAL

In areas with persistent syphilis, to characterize persons at higher risk for transmitting syphilis.

STUDY DESIGN

Cohort study. Structured interviews of persons with early syphilis from four research centers were linked to outcomes of partner tracing.

RESULTS

Of 743 persons with syphilis, 229 (31%) reported two or more partners in the previous month, and 57 (8%) received money or drugs for sex in the previous three months. Persons with at least one partner at an earlier stage of syphilis than themselves were defined as transmitters; 63 (8.5%) of persons with early syphilis met this definition. Having concurrent partners (two or more in one week in the last month) was independently associated with being a transmitter.

CONCLUSION

Sexual network/behavioral characteristics of syphilis patients and their partners, such as concurrency, can help identify persons at higher risk for transmitting syphilis who should receive emphasis in disease prevention activities.

Effect of hyperoxia on vascular endothelial growth factor levels in a wound model

HYPOTHESIS

Hyperbaric oxygen (HBO) therapy increases vascular endothelial growth factor (VEGF) levels in wounds.

DESIGN

Wounds were monitored for oxygen delivery during HBO treatment, and wound fluids were analyzed for VEGF and lactate on days 2, 5, and 10 following wounding.

SETTING

Experimental animal model.

INTERVENTIONS

Rats were randomized to HBO therapy and control groups. The HBO therapy was administered for 90 minutes, twice daily with 100% oxygen at 2.1 atmospheres absolute. Treatment was administered for 7 days following wounding.

MAIN OUTCOME MEASURES

Vascular endothelial growth factor, PO(2), and lactate levels in wound fluid were measured on days 2, 5, and 10.

RESULTS

Wound oxygen rises with HBO from nearly 0 mm Hg to as high as 600 mm Hg. The peak level occurs at the end of the 90-minute treatment, and hyperoxia of lessening degree persists for approximately 1 hour. The VEGF levels significantly increase with HBO by approximately 40% 5 days following wounding and decrease to control levels 3 days after exposures are stopped. Wound lactate levels remain unchanged with HBO treatment (range, 2.0-10.5 mmol/L).

CONCLUSIONS

Increased VEGF production seems to explain in part the angiogenic action of HBO. This supports other data that hypoxia is not necessarily a requirement for wound VEGF production.

A viral gastroenteritis outbreak associated with person-to-person spread among hospital staff

OBJECTIVE

To identify the etiologic agent and risk factors associated with a hospital ward outbreak of gastroenteritis.

SETTING

A regional referral hospital in upstate South Carolina.

METHODS

We reviewed patient charts, surveyed staff, and tested stool from acutely ill persons. A case was defined as diarrhea and vomiting in a staff member or patient from January 5 to 13, 1996.

RESULTS

The initial case occurred on January 5 in a staff nurse who subsequently was hospitalized on the ward and visited by many staff colleagues. The staff were at a significantly greater risk for gastroenteritis than were patients (28/89 [31%] vs 10/91 [11%]; relative risk [RR], 2.9; 95% confidence interval [CI95], 1.5-5.5). All 10 case-patients had been exposed to case-nurses (assigned nurses who were primary caretakers), and eight had documented exposure to case-nurses 1 to 2 days before their illness. Patients exposed to case-nurses had a significantly increased risk of illness (8/57 [14%] vs 0/32; RR, >4.5; CI95, undefined). Neither staff nor patients had significantly increased risk from food, water, ice, or exposure to case-patients. Electron microscopy identified small round-structured viruses (SRSVs) in nine of nine stool samples.

CONCLUSION

This nosocomial outbreak of gastroenteritis was likely caused by SRSVs introduced by a staff member and spread via person-to-person transmission from and among staff. The potential for spread of SRSV-associated gastroenteritis from and among staff should be considered in developing strategies to prevent similar outbreaks in hospital settings.

Allergic contact dermatitis to bisphenol-A-glycidyldimethacrylate (BIS-GMA) dental resin associated with sensitivity to epoxy resin

A patient presented with recurrent facial dermatitis associated with dental work. Dermatology referral identified the cause as allergic contact dermatitis to the epoxy acrylate BIS-GMA. Occupationally-induced allergic contact dermatitis to epoxy resin was also demonstrated. A structurally distinct aliphatic acrylate was successfully substituted. Contact sensitivity to BIS-GMA is reviewed and the potential for epoxy sensitive patients to cross-react to BIS-GMA is discussed.

Providers of syphilis care in the southern United States

BACKGROUND AND OBJECTIVES

The nadir in syphilis incidence in the 1950s provided evidence that current control methods could eliminate the transmission of syphilis. Planning such an effort will require information on the current state of the public and private infrastructure for the control of sexually transmitted disease (STD).

GOAL OF THIS STUDY

To evaluate the accessibility, acceptability, and quality of delivery of clinical and preventive outreach services for syphilis control in the southern United States.

STUDY DESIGN

A telephone-and-questionnaire survey of the 7 largest southern city, 10 state, and 9 nonsouthern comparison state STD control programs.

RESULTS

The gender-race composition of public-sector STD providers is very different from their clients. Median ratio of STD clinicians per 1994 infectious syphilis patient was 0.08 (0.01-0.25) in southern states and 0.50(0.07-1.00) in comparison states. The proportion of clients treated within one day of care-seeking in southern states was 58% to 100%; regions with inadequate access were common. A median of 45% to 50% of patients with presumptive congenital syphilis underwent recommended diagnostic procedures.

CONCLUSIONS

Serious deficiencies exist in the accessibility of STD care in the south that make the elimination of syphilis transmission difficult using current clinic-based diagnosis and treatment. A more community-based program of case finding and presumptive treatment may be indicated.

A cross-sectional study of herpes simplex virus types 1 and 2 in college students: occurrence and determinants of infection

Occurrence rates and determinants of infection with herpes simplex virus types 1 and 2 (HSV-1 and HSV-2) were measured in first- and fourth-year undergraduate students at a state university. This cross-sectional multistage probability sample survey included sociodemographic characteristics, sexual behavior patterns, disease history, and HSV type-specific antibody status. The prevalence of HSV-1 antibody was 37.2% in freshmen and 46.1% in fourth-year students; that for HSV-2 antibody was 0.4% and 4.3%, respectively. A history of cold sores was obtained in 25.6% of the freshmen; none had a history of manifest genital herpes. A history of cold sores was obtained in 28% and a history of genital herpes in 1.1% of the fourth-year students. The case-weighted prevalence of HSV-1 and HSV-2 antibodies was found to be significantly elevated for a number of student characteristics. However, multiple logistic regression analyses indicated that the significant predictors of HSV-1 antibodies in this population were female gender, black race, first intercourse at age less than or equal to 15 years, total years of sexual activity, history of a partner with oral sores, and a personal history of a non-HSV sexually transmitted disease (STD). Predictors of HSV-2 antibody were black race, duration of sexual activity, and history of a non-HSV STD.

Quality control of BCG vaccine by WHO: a review of factors that may influence vaccine effectiveness and safety

WHO oversees the quality control of BCG vaccine via a system that includes regular testing of products by in vitro methods and clinical trials. Three parent strains of BCG (Glaxo-1077, Tokyo-172, and Pasteur-1173P2) account for over 90% of the vaccines currently in use worldwide. Important characteristics of the vaccine preparations are summarized here, along with their physical-chemical properties. In instances where diagnostic criteria for tuberculosis are stringent, there is no evidence that when administered to newborns different preparations of BCG vaccine exhibit different efficacies; however, the incidence of BCG-associated adverse reactions does correlate with the type of preparation. Other factors, including dose, administration technique, and recipient characteristics are also important in determining vaccine-associated reactions.

Characterization of an antibody-binding epitope from the 18-kDa protein on Mycobacterium leprae

A murine mAb, designated L5, appears to be specific for an epitope on a protein from Mycobacterium leprae of restricted distribution within the mycobacteria. This protein, of Mr 18,000 (18 kDa) is of interest because monoclonal antibodies raised against it do not appear to cross-react with other mycobacterial pathogens. The L5 antibody-binding epitope has been mapped by two complementary methods; expression of gene fragments and synthesis of short peptides. This L5-binding region of the 18-kDa protein (amino acids 109 to 115) shows some homology to a region of the GroEL heat shock family of proteins. Characterization of this antibody-binding epitope may lead to a reagent of use in early diagnosis of infection.

Characterization of an antibody-binding epitope from the 18-kDa protein on Mycobacterium leprae

A murine mAb, designated L5, appears to be specific for an epitope on a protein from Mycobacterium leprae of restricted distribution within the mycobacteria. This protein, of Mr 18,000 (18 kDa) is of interest because monoclonal antibodies raised against it do not appear to cross-react with other mycobacterial pathogens. The L5 antibody-binding epitope has been mapped by two complementary methods; expression of gene fragments and synthesis of short peptides. This L5-binding region of the 18-kDa protein (amino acids 109 to 115) shows some homology to a region of the GroEL heat shock family of proteins. Characterization of this antibody-binding epitope may lead to a reagent of use in early diagnosis of infection.