Galveston County Research Articles

Beyond the Bench: Flagging Environmental Health Awareness on Beaches

During the summer months, folks flock to the beach to enjoy the combined pleasures of sun and sea. Smart beachgoers know that before they take a dip, they should check whether any warning flags are flying, indicating hazardous conditions such as rip currents or the presence of jellyfish. Now, Galveston swimmers can look for a new “environmental alert” flag. The new flag warns beachgoers of air and weather conditions that could pose a health threat, especially to particularly vulnerable populations such as asthmatics, the elderly, and people with heart or lung disease. The new flag reflects the translation of research findings into concrete community health education by investigators in the Asthma Pathogenesis Core of the University of Texas Medical Branch (UTMB) and codirectors of the Asthma Community Outreach and Education Core (COEC), in partnership with the Galveston Sheriff’s Office Beach Patrol, the Galveston Park Board of Trustees, and the Texas Commission on Environmental Quality. Three years ago, investigators Sharon A. Petronella and Edward G. Brooks initiated the Gulf Coast Study of Urban Air Quality and Respiratory Function (GC SURF) to study pulmonary function in a cohort of lifeguards in Galveston. During the summers of 2003 through 2005 they collected pulmonary effects data on the GC SURF cohort by using portable spirometers, which measure the amount of inhaled and exhaled air. This allowed them to evaluate exposure to and effects of air pollutants and weather conditions including nitric oxide, nitrogen dioxide, ozone, particulate matter, wind speed, outdoor temperature, relative humidity, and solar radiation. The data gathered helped the investigators determine particular times of day when changes in air quality could affect breathing health. Now, whenever the Texas Commission on Environmental Quality deems that air quality conditions exist that might affect vulnerable populations, the city’s 26 lifeguard towers and 7 free-standing beach stations deploy an orange flag and display information on posters and in brochures describing the particular environmental issues and guidelines for protecting health. The program, which the COEC believes to be the first in the nation to enlist lifeguard participation in an environmental health public warning system, provides educational materials on ozone, fine particulates, and, as needed, red tide. The group has now also developed a partnership with the Galveston County Health District to display the environmental flags at each tower when water quality is less than optimal. Petronella says the alert program is the result of a true collaborative effort between the partner organizations and is a solid indication of what can happen when a community comes together. The developers, who hope the orange flag alert program can be used as a model for other beaches, presented it at the annual meeting of the U.S. Lifesaving Association in Galveston in 2004. In addition to the GC SURF flag alert program, the Asthma Pathogenesis Core of the UTMB COEC is also involved in other projects that focus on building connections between research, education, and community health. One of these, the Texas Emergency Department Asthma Surveillance Project, is a collaborative effort coordinated by Charles Macias of Baylor College of Medicine that links the databases of Baylor and three other Texas hospitals to track asthma-related emergency room visits. The results will aid in the development of an educational intervention program. Another project, Communities Organized Against Asthma and Lead, is an environmental justice consortium combining the educational outreach efforts of the COEC with community social services and health care providers. COEC investigators are also involved in a school asthma surveillance project. “As researchers involved in the UTMB NIEHS Center Asthma Pathogenesis Core, we work in and with our community to identify problems and potential solutions related to our environment,” says Petronella. “Our COEC, however, allows us to take our work one crucial step further––by actually assisting the community with education, intervention, and development of policies that will effect positive change in the health of our residents and all visitors to our part of the Gulf Coast.” In essence, Petronella says, the COEC forms the bridge from basic science to the public. “This is essential to our success,” she adds, “since the key to any public health research program is the use to which the data are put.”

Mapping the Vulnerability to Potential Toxic Substance Releases from Industrial Facilities under Emergency Situations: A Case Study of Galveston, Texas

This research investigates the spatial variations of vulnerability to toxic substance releases under possible emergency outbreaks in Galveston County, Texas. By identifying the potential risk and measuring the extent of possible impact, we provide useful information for the local government and the public to develop more effective evacuation strategies. Assuming that toxic substance releases occur during a worst-case scenario, we determine the vulnerability based on a combination of five factors at the census block level: (1) population density; (2) the percentage of people under 5 years old and above 65; (3) distance between residence and hazardous sites; (4) road network capacity; (5) density of hazardous sites. We employ the Areal Locations of Hazardous Atmospheres (ALOHA) dispersion model to define the impact areas. We calculate an index for each of the five factors. We weigh the indices equally and generate the overall vulnerability index. Results are visualized in a GIS environment.

Association Between Sudden Death in Infancy and Co-Sleeping

Our retrospective case review from 1978-2002, of infant deaths autopsied under the auspices of the Galveston County Medical Examiner Office, demonstrated a lack of detailed scene investigation, including sleeping circumstances and arrangements, as well as a pattern of ascribing the cause of death to SIDS even when there is evidence of a hazardous sleeping arrangement. During this period, 89/103 pediatric deaths were certified as SIDS and 39/103 of these were co-sleeping, 51/103 were sleeping alone, and 17/103 had no sleeping arrangement indicated. Upon review, there were only 6 cases where the scene visitation was documented. Only 9 cases used an Infant Death Investigation Form (IDIF), and this only started in 1999. The IDIF contains questions regarding the infants' sleep environment (bedding descriptions, co-sleeping, sleep surface) not used in the standard medical examiner death investigative forms. There has been an upward trend since the late 1990s in the number of scenes visited and detailed descriptions of the scenes, likely due to the increased awareness of hazardous infant sleeping conditions identified by American Academy of Pediatrics and U.S. Consumer Product Safety Commission. The association between co-sleeping and sudden infant death remains controversial among clinicians. We report a high association between these two conditions.

High anxiety is associated with an increased risk of death in an older tri-ethnic population

Background and Objectives The health consequences of anxiety in late life have not been adequately investigated. We sought to examine the association between anxiety and death in an older tri-ethnic population. Methods A longitudinal population-based study of 506 older noninstitutionalized non-Hispanic Whites, non-Hispanic Blacks, and Hispanics aged 75 years or older from Galveston County. Results Average age was 80.8 (SD 4.4) and 50.8% were women. Older non-Hispanic Whites (21.6%) reported the highest prevalence of anxiety, followed by Hispanics (12.4%) and non-Hispanic blacks (11.3%) ( P = .0001). High anxiety was significantly associated with an increased hazard of all cause death (HR 1.52; 95% CI 1.02, 2.28) and cardiovascular death (HR 1.90; 95% CI 1.06, 3.36); and was associated with an increased hazard of cancer death (HR 2.38; 95% CI 0.88, 6.45) during 5-years of follow-up. Conclusion There is a high prevalence of anxiety in late life. Our results indicate an association between anxiety and increased risk of death in persons aged 75 and older.

Parental Perception and Knowledge of Correct Use of Car Seats in Galveston County

Parental Perception and Knowledge of Correct Use of Car Seats in Galveston County

Preferences of husbands and wives for outcomes of prostate cancer screening and treatment.

To explore the preferences of male primary care patients and their spouses for the outcomes of prostate cancer screening and treatment, and quality of life with metastatic prostate cancer. Cross-sectional design. Primary care clinics in Galveston County, Texas. One hundred sixty-eight couples in which the husband was a primary care patient and a candidate for prostate cancer screening. Preferences were measured as utilities for treatment outcomes and quality of life with metastatic disease by the time trade-off method for the husband and the wife individually and then conjointly for the couple. For each health state considered, husbands associated lower utilities for the health states than did their wives. Couples' utilities fell between those of husbands and wives (all comparisons were significant at P <.01). For partial and complete impotence and mild-to-moderate incontinence, the median utility value for the wives was 1.0, indicating that most wives did not associate disutility with their husbands having to experience these treatment complications. Male primary care patients who are candidates for prostate cancer screening evaluate the outcomes of prostate cancer treatment and life with advanced prostate cancer as being far worse than do their wives. Because the choice between quantity and quality of life is a highly individualistic one, both the patient and his partner should be involved in making decisions about prostate cancer screening. J

Ethnic differences in antihypertensive medication use in the elderly.

Determining the optimal treatment for hypertension in very old patients requires better understanding of interethnic differences in patterns and predictors of antihypertensive drug use in this population. To investigate interethnic variations in antihypertensive drug use in a tri-ethnic sample of community-dwelling adults aged > or =77 years. We performed a cross-sectional study of non-Hispanic white, black, and Hispanic adults > or =77 years old residing in Galveston County, TX. In-home interviews in 1997 and 1998 assessed blood pressures and antihypertensive medication use in 281 subjects who reported having hypertension or who had a systolic blood pressure > or =140 mm Hg and/or diastolic blood pressure > or =90 mm Hg. Of the population evaluated, 62.9% of non-Hispanic whites, 60.2% of blacks, and 45.2% of Hispanics with hypertension were on antihypertensive medications (p < 0.027 across the ethnic groups). After adjusting for age, gender, years of education, household income, Medicaid insurance, number of physician visits, and cognitive function, Hispanic ethnicity, unlike black ethnicity, continued to be significantly associated with lower use of antihypertensive drugs compared with non-Hispanic whites (OR 0.41; 95% CI 0.19 to 0.90). Characteristics associated with the lower use of antihypertensive drugs included older age and low income in whites, poor cognition and infrequent physician visits in blacks, and lack of Medicaid insurance in Hispanics. In the elderly, Hispanic ethnicity, unlike black ethnicity, is significantly associated with lower use of antihypertensive drug therapy compared with non-Hispanic white ethnicity, adjusting for relevant sociodemographic and health factors.

Cognitive and functional decline in adults aged 75 and older.

To simultaneously examine the influence of functional disability on the development of cognitive impairment and the influence of cognitive status on the development of functional disability over time and compare findings across ethnic groups. A population-based longitudinal study. Galveston County, Texas. Three hundred sixty-five community-dwelling Hispanic Americans, African Americans, and non-Hispanic whites, aged 75 and older. Baseline measures included demographics, self-reported chronic medical conditions, functional disability, and cognitive status. Longitudinal measures included functional decline and cognitive decline. Substantial functional decline was associated with each additional error on the mental status measure; substantial cognitive decline was associated with each additional antecedent disability. These findings were evident across all three ethnic groups, even when taking into account the effects of demographic factors and chronic health conditions, although the specific chronic health conditions that influenced cognitive and functional decline were found to vary across the three ethnic groups. Our findings suggest that, rather than simply being correlated markers of increasing frailty, cognitive and functional decline appear to influence the development of one another. Clinicians need to be aware of these associations, which may affect the direction of preventive care and rehabilitation in the oldest old. Appropriate intervention may result in the prevention or delay of functional disability and cognitive decline. Awareness of the specific chronic health conditions that increase the risk for cognitive or functional decline in various ethnic groups, and the effect of comorbid disease, may also help efforts to prevent decline in older adults.

Combined Homicide-Suicide in Galveston County

Combined homicide-suicides have been classified based on the psychopathology of the perpetrator and the nature of the relationship between perpetrator and victim(s). To further understand the nature of this tragic phenomenon and to test the validity and practicality of a previously suggested classification system, investigators systematically collected data on all combined homicide-suicide events that occurred in Galveston County, Texas over a continuous 18-year period (n = 20). The most common psychopathological finding for perpetrators was high serum alcohol levels that suggested intoxication. Most combined homicide-suicides fell into one of the relational categories and most of these, as predicted, were of the consortial type, possessive subtype. As expected, due to the small sample size, the less common types of combined homicide-suicide were not represented in this sample.

Aging versus disease: the opinions of older black, Hispanic, and non-Hispanic white Americans about the causes and treatment of common medical conditions.

Little is known about how older people interpret disease and how those interpretations might relate to use of medical services. To assess opinions of older subjects about the cause and treatment of common diseases and how they are related to health behaviors. In-home interview of a population-based sample (n = 601) of noninstitutionalized black, Hispanic, and non-Hispanic white American men and women aged 75 and older in Galveston County, Texas. Substantial proportions of the subjects considered heart disease, arthritis, or difficulty sleeping to be a normal part of aging. In multivariate analyses including age, gender, education, marital status, living arrangement, global self-rating of health, and comorbidity, older black subjects were less likely to view heart disease (OR = 0.41; 95% CI, 0.26-0.64), arthritis (OR = 0.48; 95% CI, 0.31-0.73), or sleep problems (OR = 0.50; 95% CI, 0.32-0.77) as a normal part of aging than were non-Hispanic whites. Blacks were more than three times as likely to attribute heart disease to overwork or stress than were non-Hispanic whites. In multivariate analyses, subjects who considered all three of the medical conditions to be a normal part of aging ("fatalistic") were less likely to have received preventive medical services in the previous year (OR = 0.13; 95% CI, 0.02-0.96), and subjects who felt that nothing could be done to treat any of the conditions ("nihilistic") were less likely to have a regular physician (OR = 0.24; 95% CI, 0.08-0.74). Substantial numbers of older subjects are fatalistic about the cause of disease and/or nihilistic about its treatment. These attitudes are associated with decreased utilization of health services. Attempts to improve the health of underserved groups should employ interventions that are sensitive to the health beliefs of the targeted group.

Anxiety Symptomatology in Mexican-American Adolescents

Mexican-American adults and adolescents in general have been reported to have high levels of anxiety symptomatology. In our study of a tri-ethnic sample of 2528 junior and senior high school students, the Youth Self Report (YSR) version of the Child Behavior Checklist (CBCL) and a sociodemographic questionnaire was used to assess the anxiety symptoms of Hispanic youth. We compared the ratings on anxiety symptoms, using Achenbach's anxiety subscale on the YSR, between two populations. The anxiety levels of youth in coastal southeast Texas (Galveston County) were compared to the anxiety levels of youth in the lower Rio Grande Valley. We found that Mexican-Americans of the Lower Rio Grande Valley scored higher on anxiety symptoms than the tri-ethnic population of Galveston County. Other factors associated with higher anxiety scores for Mexican-American youths included being born outside the US, linguistic fluency, father absent from the home, mother's education, and household size. Multiple regression analyses showed that socio-economic status (SES), family composition, and linguistic fluency had a greater relative impact on anxiety symptomatology than all other factors, both for the total sample as well as for the Mexican-American sample. These results parallel previous findings, with Mexican-American adults, which suggest either higher risk for anxiety symptomatology or a culturally related bias in the reporting of such symptoms.

Behavioral Interference for Perch Sites in Two Species of Introduced House Geckos

Behavioral Interference for Perch Sites in Two Species of Introduced House Geckos

Medically Serious Suicide Attempts in a Jail with a Suicide-Prevention Program

A suicide prevention program was implemented at the Galveston County Jail in 1986, reducing the number of suicides to only one from that time until the present. In the ten years prior to the implementation of the program, there had been seven suicides. Nevertheless, there have been a number of cases of medically serious suicide attempts that have occurred since implementation of the program. Thirteen cases of suicide attempts severe enough to warrant transfer to an emergency room for medical attention were identified through jail incident reports as occurring between 1989, when improvements were made in record-keeping at the jail, and July of 1994, when this study was initiated. Hospital records, jail medical records, jail administrative records and, in some cases, competency evaluations were obtained for each case. The cases were examined regarding demographic data, psychiatric history, circumstances surrounding the act, and results of psychiatric evaluation performed after the act. The findings were then compared to studies of suicides and near-suicides in the literature. Examination of these cases has provided information that should render the suicide prevention program even more effective as well as provide useful information to other jails interested in implementing or improving a suicide-prevention program.

Folk Narratives and Archaeology: An African-American Cemetery in Texas

Participation in traditional narrative performances benefited archaeologists working on the relocation of the Albert J. Phillips Memorial Cemetery, a historical African-American cemetery in Galveston County, Texas. In addition to indicating the location of various site features, the verbal accounts provided information about site formation processes and community events, past and present, that had an effect on these processes. The incorporation of folklore methodology produced a cooperative relationship with community members, helped to diffuse a potentially volatile situation, and united the archaeologists and the community in the common goals of cooperation, knowledge, and understanding.

Avoidable hospitalizations and socio-economic status in Galveston County, Texas.

Population-based hospitalization rates for preventable conditions are derived for a low-income population in Galveston County, Texas using discharge data from four area hospitals and demographic data from the U.S. Census. Comparisons are made with similar rates for the general populations of two eastern states (Maryland and Massachusetts) and New York City. Results support the hypothesis that low-income persons lack access to primary care, leading to higher rates of hospitalization for preventable conditions. Alternative explanations for differences found are examined.

The Incompetent Defendant: Support Systems Help Avoid Future Legal Problems

Reducing crime and improving efficiency of our criminal justice system should be facilitated by identifying how to treat and manage mental health patients who are prone to committing criminal acts more effectively. A total of 142 competency evaluations were reviewed from cases evaluated by the Galveston County Forensic Psychiatrist from 1984 to 1990. Examination of data from these defendants allowed us to address the psychiatric needs of these defendants in terms of contact with the mental health system, particularly those who had more than one criminal justice system contact. The latter defendants lacked social support systems and consistent mental health system follow-up to provide stabilization of their condition. It was felt that this was a factor in their more frequent contact with the criminal justice system.

Geologic and Engineering Field Study of the Northeast Hitchcock Field, Galveston County, TX

ABSTRACT The NE Hitchcock Field is a water-drive gas reservoir producing from the Oligocene Frio Formation. The structure in the field is a series of growth-fault bounded rollover-anticlines. In the field, the Frio consists of three units. The lowest is a wave-dominated prograding delta of widespread extent. The upper unit is a wave-dominated transgressive beach/barrier bar. The middle unit is an erosively based channel deposit, which has cut into the prograding delta. Recurrent movement on faults which existed at the time of Frio deposition localized channel erosion. The valleys created by the erosion were filled with very clean and permeable sands deposited by fluvial or estuarine processes. The aquifer which supports the NE Hitchcock water-drive is separated into many fault-bounded blocks. Movement on the blocks may range from zero to 60 feet. The pressure histories of the field indicate that the wells are in pressure communication, thereby identifying the fault system as non-sealing. Combining the production histories with the pressures, gas/water contacts were mapped for several time intervals. Tracking the movement of the contacts indicates that preferential fluid flow paths exist. The fault system may be a conduit for water encroachment to the producing wells. The highly permeable channel sands may also be preferential fluid pathways. Integrating the geological and engineering disciplines resulted in a reservoir simulation of the field which emphasized the heterogeneities, and modelled the fluid movement through the aquifer. End_of_Record - Last_Page 253-------

Cloacal Sperm in Spring Migrants: Occurrence and Interpretation

Cloacal sperm were studied microscopically in cloacal lavages from 448 birds representing 70 migratory species, from Galveston, Texas, and Foley, Missouri. Representatives of 20 of these species sampled in the spring had cloacal sperm; at least 38 of the 39 individuals with sperm were males. A conservative interpretation of cloacal sperm in male migrants is that they represent spontaneous discharge from the ductus deferens or its glomus seminale, specifically in individuals that are ready for breeding. Although most of the migrants with cloacal sperm were not far from the known nesting range of the species, others were 30 to 900 km south of the southern limits of the known breeding range (Nashville Warbler [Vermivora ruficapilla], Rose-breasted Grosbeak [Pheucticus ludovicianus] and Painted Bunting [Passerina ciris]). There appear to be functionally significant differences among species of passerine birds in the timing of sperm emission and the physiological readiness for breeding; these processes apparently start in some species during spring migration. This study is based chiefly upon my systematic collection and analysis of cloacal lavages (washes) from feral birds. The initial purpose of the lavage technique and its application during banding and field studies was to ascertain the feasibility of developing rapid, noninvasive, and repeatable methods for identifying the sex and physiological state of individual birds in the course of field studies and under natural conditions. My first notable finding from the use of this technique was that spermatozoa (sperm) can be found in the cloaca of reproductively active individuals of either sex and particularly in a number of passerines (Quay 1984a, b). This led to the present study, which had the goals of: (1) determining the occurrence ofcloacal sperm in male spring migrants, (2) comparing species in these occurrences, (3) comparing results from two localities (Galveston, Texas, and Foley, Missouri) representing two latitudes in the central zone through the United States, and (4) making a start in determining the biological meaning of sperm in the cloacas of male migrants. A general review of some of this work has appeared in an abstract (Quay 1984b). STUDY AREAS AND METHODS I captured birds by mist nets, banded them and gave them cloacal lavages. During 1982, netting was done in the back and side yards of my residence at the NE end of the town of Galveston, Galveston County, Texas. Nets were in operation 6 and 14-31 March, 1-4, 14-21, and 25-30 April, and 1-13, 22, 26, 30 and 31 May, generally from before dawn to after sunset, and with breaks in the morning and afternoon. During 1983, the study area was a farm with mixed habitats on the bluffs on the W side of the Mississippi River, 5 km (airline) NNW of the town of Foley, Lincoln County, Missouri. Here, up to 16 nets were op ra ed continuously from early in the day 30 April through early in the day 7 May 1983 (total = 98 net-days). Nets were inspected at approximately hourly intervals during the day and less frequently at night. At both localities, I personally captured and processed all birds. After capture, birds were placed in individual light-weight, brown paper bags until processed about 5-20 min later. The procedural steps are noted here for two reasons: (1) they provide the basis for determinations of sex, age-class, and possible correlates of occurrences of cloacal sperm, and (2) they may possibly be related to presence or absence of cloacal sperm in some individuals or species through physical handling. Therefore, to facilitate the obtaining and interpreting of results of subsequent studies, all of the methods that I used are noted. These were: (1) weighing with a Mettler Type P-120 top-loading balance to the nearest 0.1 g; (2) measurement of wing chord and tail lengths; (3) determination of sex and age-class insofar as possible; (4) recording, where relevant, external characteristics such as the relative development of the cloacal protuberance of males, the size and degree of edema of the incubation/ br od patch, and skull pneumatization; (5) banding; and (6) the taking of cloacal lavages. Procedures (2) through (5) above followed those of the North American Bird Banding Manual vol. II (Bird Banding Techniques) (Bird Bandi g Offices of the United States and Canada 1977). Determination of sex and age-class

Seasonal Calling, Foraging, and Flocking of Inca Doves at Galveston, Texas

-Inca Doves (Scardafella inca) were studied in Galveston, Texas, from August 1977 through March 1981, with the aim of evaluating the occurrence and nature of quantitative seasonal changes in behavior. Three such behaviors are described and analyzed: (1) number of midday-calling (co-oh cooo) birds; (2) estival foraging in large open fields; and (3) winter flocking. The vernal increase phase of the first of these had positive and significant (P < 0.001) regressions with daylength during each of two consecutive years, and showed little if any relation with minutes of sun, or with temperatures, during census days. Daily timing of foraging in large open fields during summer was highly consistent for three consecutive years, with peak numbers in late afternoon. Winter flocking behavior was more variable. Although these behaviors can be seen at any season, they show significant quantitative seasonal changes or patterns in this species near the northern limit of its subtropical geographic range. Knowledge of avian seasonal chronoethology is dominated by information and concepts obtained chiefly from studies on species in which seasonal changes are obviously great. These studies also tend to stress such major or dramatic biological aspects as sexual behavior, reproduction, growth, and migration. However, this emphasis appears to inadvertently obscure what may be the near universality of seasonal adaptations, and the mechanisms and plasticity whereby they come into being. Inca Doves (Scardafella inca) in southwestern United States represent a good species for studies on the nascence and plasticity of avian seasonal behavior. Their populations are thought to be nonmigratory. They apparently vary from being reproductively active throughout the year in Central America, to having only a brief midwinter hiatus in reproduction in southwestern United States (Bent 1932, Heilfurth 1934, Johnston 1960, Oberholser 1974). Inca Doves in Galveston, Texas, are near the northeastern limit of their geographic range. Although they are now one of the most common urban birds in Galveston, their arrival here is recent (Oberholser 1974). Thus they serve as an example of a northward moving, nonmigratory, subtropical species whose environmental responses and limits are largely undefined and not yet investigated in detail. Some aspects of their water and salt balance, thermoregulation and metabolism have been described by MacMillen and Trost (1965, 1966, 1967a, b) under laboratory conditions. The present study aimed to evaluate the occurrence of seasonal differences in observed and counted behaviors in the Inca Dove population of eastern Galveston. The longer-term objectives of this work are to provide a basis for correlative evaluation of particular meteorological and other environmental factors in avian and Inca Dove seasonal adaptation, and to provide information on aspects of the urban biology and ecology of this species. STUDY AREAS AND METHODS My primary data were obtained through systematic observation in two study areas within the city limits of Galveston, Galveston County, Texas. The first of these consisted of large fields at the eastern end of the city (darkened area, Fig. 1). During the first part of the study (9 August 1977 to 27 July 1978) there were four fields of 0.75, 2.76, 2.89 and 3.24 ha. By 17 January 1980, only two remained (1.28 and 2.76 ha) due to development. During most of the year the fields were mowed approximately weekly, and at all seasons vegetation was sufficiently low to permit easy detection of all birds. I counted all birds on the ground in these fields during censuses made at different times of the day from 9 August 1977 through March 1981 (censuses per year: 1977, 267; 1978, 755; 1979, 670; 1980, 619; 1981, 161; total 2,472). The second study area was in the urbanized part of eastern Galveston, from the southwestern corner of the campus of the University of Texas Medical Branch to the center of the downtown business district. I followed a standardized course on foot (heavy line, Fig. 1) during the middle of the day (10:00 to 13:00), with consistent total times and direction of census-taking. Along this route I made two kinds of censuses simultaneously. In the first, I counted all birds on the ground in specific lots or yards and noted their activities and associations. Total area of all yards and lots

Aedes aegypti in a Texas coastal county as an index of dengue fever receptivity and control.

Since Galveston County, Texas, is one of the high risk areas for the reintroduction of dengue, we have maintained an Aedes aegypti surveillance program since 1977 by using ovitraps to determine the density and distribution of this species in 17 communities. A. aegypti adults were present primarily from May thrugh November, with higher positive ovitrap rates associated with periods of low rainfall. Larvae collected from six different communities, when compared with a standard, insecticide-susceptible strain exhibited only 2 X greater tolerance to malathion and chlorpyrifos. Similar results were obtained with malathion susceptibility tests of adults. Ultra-low volume malathion treatments of caged A. aegypti in a residential city block yielded good kills in the proximal but not the distal half of the block. Ovitraps in a two square-block area, treated with single pellets of chlorpyrifos, were less frequently positive and contained a smaller average number of eggs per trap than untreated traps in the surrounding area.