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A Case Study Of Pediatric Diarrhea At Murchison District Hospital In Port Shepstone, Kwazulu-Natal, South Africa, T. Smith

Independent Study Project (ISP) Collection

This study investigates pediatric diarrhea in children under 5 years old at Murchison District Hospital in Port Shepstone, South Africa. Hospital Child Pip data was used to determine the number of admissions to the hospital for pediatric diarrhea and its mortality rate. Characteristics of deceased patients including age, malnutrition, and HIV status, were then synthesized with information on patients’ access to clean water and improved sanitation obtained through 20 interviews of mothers of patients as well as caregivers’ infant feeding practices and hygiene practices, such as handwashing with soap. Treatment and prevention of diarrhea was also explored. Murchison’s management of …

Down-Regulation Of Natural Killer Cell Activation In Response To Influenza Virus In Older Adults, Yu Jing

Theses and Dissertations in Biomedical Sciences

Immune senescence contributes to influenza-associated high mortality and morbidity and reduced vaccine efficacy in elderly people. Type I T cell (Thl)-mediated immunity plays a significant role in Immune responses to influenza infection and vaccination. Natural killer (NK) cells secrete significant amount of IFN-7 , a hallmark Thl cytokine, in response to influenza infection. How aging influences human NK cell IFN-7 production in response to influenza virus has not been well documented. In this study we employed human peripheral blood mononuclear cells (PBMC) and performed intracellular cytokine staining and flow cytometry primarily to investigate how aging influences NK cell activation with …

Water Source Outbreaks, Policy, And The South Bass Island Investigation, David Brett-Major, Sherry M. Brett-Major

Journal Articles: Epidemiology

No abstract provided.

A Likelihood Based Method For Real Time Estimation Of The Serial Interval And Reproductive Number Of An Epidemic, Laura Forsberg White, Marcello Pagano

Harvard University Biostatistics Working Paper Series

No abstract provided.

Stability Analysis For An Seir Age-Structured Epidemic Model Under Vaccination, M. El-Doma

Applications and Applied Mathematics: An International Journal (AAM)

An SEIR age-structured epidemic model is investigated when susceptible and immune individuals are vaccinated indiscriminately and the force of infection of proportionate mixing type. We determine the steady states and obtain an explicitly computable threshold condition, and then study the stability of the steady states.

Global Stability Results And Well Posedness Of An Si Age-Structured Epidemic Model With Vertical Transmission, M. El-Doma

Applications and Applied Mathematics: An International Journal (AAM)

An SI age-structured epidemic model for a vertically as well as horizontally transmitted disease is investigated when the fertility and mortality rates depend on age and the force of infection of proportionate mixing assumption type. We prove the well posedness of the model as well as the global stability for endemic equilibriums.

Spatio-Temporal Analysis Of Areal Data And Discovery Of Neighborhood Relationships In Conditionally Autoregressive Models, Subharup Guha, Louise Ryan

Harvard University Biostatistics Working Paper Series

No abstract provided.

Cutaneous And Presumed Visceral Leishmaniasis In A Soldier Deployed To Afghanistan, James P. Woodrow, Joshua D. Hartzell, Jim Czarnik, David Brett-Major, Glenn Wortmann

Journal Articles: Epidemiology

Leishmaniasis has been frequently diagnosed in US military personnel returning from duty in Southwest Asia. The majority of cases have demonstrated cutaneous disease, although a few cases of visceral disease have been documented. We present the case of an immunocompetent, HIV-negative, US Army soldier who suffered both visceral and cutaneous manifestations of leishmaniasis after returning from deployment in Afghanistan. Overlap of cutaneous and visceral involvement is rare and has not been reported in our cohort. Latent Plasmodium vivax infection may have been an exacerbating cofactor. We discuss this case and present a review of the literature.

Laboratory Diagnosis Of Tuberculosis In Primary Care, David Brett-Major, Thomas E. Walsh

Journal Articles: Epidemiology

No abstract provided.

The Association Between Breast Feeding And Being Overweight In Children, Naja Jamil Eldanaf

Theses and Dissertations

Purpose: Obesity/Overweight in children is an epidemic and the most common disorder of childhood in the developed world. Prevalence is increasing, leading to short- and long-term complications. Breastfeeding may protect against childhood obesity, but the debate is ongoing. The main purpose of this project was to assess the relationship between breastfeeding and being overweight in early childhood.Methods: Data were collected from the State and Local Area Integrated Telephone survey; National Survey of Children's Health, 2003. Overall, 16,358 children, ages 3 to 5, were included in the sample. SPSS Complex Sample software was utilized to generate for all analyses. Complex samples …

Chaotic Desynchronization Of Multistrain Diseases, Ira Schwartz, Leah Shaw, Derek Cummings, Lora Billings, Marie Mccrary, Donald Burke

Department of Mathematics Faculty Scholarship and Creative Works

Multistrain diseases are diseases that consist of several strains, or serotypes. The serotypes may interact by antibody-dependent enhancement rADE, in which infection with a single serotype is asymptomatic, but infection with a second serotype leads to serious illness accompanied by greater infectivity. It has been observed from serotype data of dengue hemorrhagic fever that outbreaks of the four serotypes occur asynchronously. Both autonomous and seasonally driven outbreaks were studied in a model containing ADE. For sufficiently small ADE, the number of infectives of each serotype synchronizes, with outbreaks occurring in phase. When the ADE increases past a threshold, the system …

Secular Trends In Life Expectancy By Diet Status Among Never Smoking Seventh-Day Adventists, Noha Salim Daher

Loma Linda University Electronic Theses, Dissertations & Projects

To evaluate how life expectancy changed by age and secular time from 1960 through 1988, two cohort studies, the Adventist Mortality Study (AMS, 1960-1985, n = 27,530) and the Adventist Health Study (AHS, 1976-1988, n = 34,192) were combined. The life expectancy of omnivores was compared to vegetarians separately in never-smoking males and females for all-cause mortality, and where the cause of death was cardiovascular disease or all site-cancer. Life expectancies were calculated for subjects who had survived to ages 30, 50, 70, and 80 during six calendar periods: 1960- 1964, 1965-1969, 1970-1974, 1975-1979, 1980-1984, and 1985-1988. Ten-year calendar periods …

History-Adjusted Marginal Structural Models: Optimal Treatment Strategies, Maya L. Petersen, Mark J. Van Der Laan

U.C. Berkeley Division of Biostatistics Working Paper Series

Much of clinical medicine involves choosing a future treatment plan that is expected to optimize a patient's long-term outcome, and modifying this treatment plan over time in response to changes in patient characteristics. However, dynamic treatment regimens, or decision rules for altering treatment in response to time-varying covariates, are rarely estimated based on observational data. In a companion paper, we introduced a generalization of Marginal Structural Models, named History-Adjusted Marginal Structural Models, that estimate modification of causal effects by time-varying covariates. Here, we illustrate how History-Adjusted Marginal Structural Models can be used to identify a specific type of optimal dynamic …

The Global Distribution Of Disease And Death, Jeffrey Colman Salloway

The University Dialogue

No abstract provided.

A Pilot Randomized, Controlled Trial Of An In-Home Drinking Water Intervention Among Hiv + Persons, John M. Colford, Sona R. Saha, Timothy J. Wade, Catherine C. Wright, Mai Vu, Sandra Charles, Peter Jensen, Alan Hubbard, Deborah A. Levy, Joseph N. S. Eisenberg

Journal Articles: Epidemiology

Although immunocompromised persons may be at increased risk for gastrointestinal illnesses, no trials investigating drinking water treatment and gastrointestinal illness in such patients have been published. Earlier results from San Francisco suggested an association (OR 6.76) between tap water and cryptosporidiosis among HIV + persons. The authors conducted a randomized, triple-blinded intervention trial of home water treatment in San Francisco, California, from April 2000 to May 2001. Fifty HIV-positive patients were randomized to externally identical active (N = 24) or sham (N = 26) treatment devices. The active device contained a filter and UV light; the sham provided no treatment. …

A Randomized, Controlled Trial Of In-Home Drinking Water Intervention To Reduce Gastrointestinal Illness, John M. Colford, Timothy J. Wade, Sukhminder K. Sandhu, Catherine C. Wright, Sherline Lee, Susan Shaw, Kim Fox, Susan Burns, Anne Benker, M. Alan Brookhart, Mark Van Der Laan, Deborah A. Levy

Journal Articles: Epidemiology

Trials have provided conflicting estimates of the risk of gastrointestinal illness attributable to tap water. To estimate this risk in an Iowa community with a well-run water utility with microbiologically challenged source water, the authors of this 2000-2002 study randomly assigned blinded volunteers to use externally identical devices (active device: 227 households with 646 persons; sham device: 229 households with 650 persons) for 6 months (cycle A). Each group then switched to the opposite device for 6 months (cycle B). The active device contained a 1-microm absolute ceramic filter and used ultraviolet light. Episodes of "highly credible gastrointestinal illness," a …

Long-Term Consequences Of West Nile Virus In Virginia., Diana Cruz Ocampo

Theses and Dissertations

Objective: The purpose of this investigation was to describe the long-term effects and functional outcomes of patients in Virginia who were reported to the Virginia Department of Health with West Nile virus (WNV) non-neuroinvasive and neuroinvasive disease. The study identified the duration of symptoms after initial illness, the number of persons who fully recovered versus the number who continue to be symptomatic and how patients' quality of life differed after illness.Methods: The study population was drawn from 60 human cases that met the surveillance case definition for non-neuroinvasive and neuroinvasive WNV illness in Virginia between 2002-2004. Information was collected during …

The Relationship Between Breastfeeding And The Development Of Asthma In Early Childhood, River Anne Pugsley

Theses and Dissertations

Purpose: Asthma can have significant adverse effects on the health and quality of life of children, and the prevalence of this condition continues to rise. Breastfeeding may protect against asthma, but some uncertainty remains. The purpose of this study was to further examine the relationship between breastfeeding and the risk of developing asthma in early childhood. Methods: Data were collected from the State and Local Area Integrated Telephone Survey: National Survey of Children's Health, 2003. The study population consisted of 33,315 children ages 0 to 5 years. Prevalence rates of asthma and breastfeeding ,were calculated, as were crude and Mantel-Haenszel …

Dynamical Epidemic Suppression Using Stochastic Prediction And Control, Ira Schwartz, Lora Billings, Erik Bollt

Department of Mathematics Faculty Scholarship and Creative Works

We consider the effects of noise on a model of epidemic outbreaks, where the outbreaks appear randomly. Using a constructive transition approach that predicts large outbreaks prior to their occurrence, we derive an adaptive control scheme that prevents large outbreaks from occurring. The theory is applicable to a wide range of stochastic processes with underlying deterministic structure.

Descriptive And Comparative Study Of The Nutritional Knowledge And Behavior Of Mothers Of Young Children Who Have Received Targeted Nutritional Education And Those Who Have Not As A Method To Ascertain The Effectiveness Of The Little Tree Nutritional And Educational Centre In Combating Malnutrition In The Pienaarsig Township Of Nieu Bethesda, Eastern Cape Province, South Africa, Amelia Peterson

Independent Study Project (ISP) Collection

No abstract provided.

History-Adjusted Marginal Structural Models And Statically-Optimal Dynamic Treatment Regimes, Mark J. Van Der Laan, Maya L. Petersen

U.C. Berkeley Division of Biostatistics Working Paper Series

Marginal structural models (MSM) provide a powerful tool for estimating the causal effect of a treatment. These models, introduced by Robins, model the marginal distributions of treatment-specific counterfactual outcomes, possibly conditional on a subset of the baseline covariates. Marginal structural models are particularly useful in the context of longitudinal data structures, in which each subject's treatment and covariate history are measured over time, and an outcome is recorded at a final time point. However, the utility of these models for some applications has been limited by their inability to incorporate modification of the causal effect of treatment by time-varying covariates. …

Seasonal Analyses Of Air Pollution And Mortality In 100 U.S. Cities, Roger D. Peng, Francesca Dominici, Roberto Pastor-Barriuso, Scott L. Zeger, Jonathan M. Samet

Johns Hopkins University, Dept. of Biostatistics Working Papers

Time series models relating short-term changes in air pollution levels to daily mortality counts typically assume that the effects of air pollution on the log relative rate of mortality do not vary with time. However, these short-term effects might plausibly vary by season. Changes in the sources of air pollution and meteorology can result in changes in characteristics of the air pollution mixture across seasons. The authors develop Bayesian semi-parametric hierarchical models for estimating time-varying effects of pollution on mortality in multi-site time series studies. The methods are applied to the updated National Morbidity and Mortality Air Pollution Study database …

Epidemiologic And Environmental Investigation Of A Recreational Water Outbreak Caused By Two Genotypes Of Cryptosporidium Parvum In Ohio In 2000, Els Mathieu, Deborah A. Levy, Fran Veverka, Mary-Kay Parrish, John Sarisky, Nancy Shapiro, Stephanie Johnston, Thomas Handzel, Allen Hightower, Lihua Xiao, Yeuk-Mui Lee, Steve York, Michael Arrowood, Robin Lee, Jeffrey L. Jones

Journal Articles: Epidemiology

In August 2000, the Ohio Department of Health requested assistance to investigate a cryptosporidiosis outbreak with more than 700 clinical case-patients. An epidemiologic and environmental investigation was conducted. Stool specimens, pool water, and sand filter samples were analyzed. A community-based case-control study showed that the main risk factor was swimming in pool A (odds ratio [OR] = 42, 95% confidence interval [CI] = 12.3-144.9). This was supported by results of polymerase chain reaction (PCR) analysis, which showed the presence of both the human and bovine genotypes of Cryptosporidium parvum in case-patients and samples from the filter of pool A. A …

Did A Severe Flood In The Midwest Cause An Increase In The Incidence Of Gastrointestinal Symptoms?, Timothy J. Wade, Sukhminder K. Sandhu, Deborah A. Levy, Sherline Lee, Mark W. Lechevallier, Louis Katz, John M. Colford

Journal Articles: Epidemiology

Severe flooding occurred in the midwestern United States in 2001. Since November 2000, coincidentally, data on gastrointestinal symptoms had been collected for a drinking water intervention study in a community along the Mississippi River that was affected by the flood. After the flood had subsided, the authors asked these subjects (n = 1,110) about their contact with floodwater. The objectives of this investigation were to determine whether rates of gastrointestinal illness were elevated during the flood and whether contact with floodwater was associated with increased risk of gastrointestinal illness. An increase in the incidence of gastrointestinal symptoms during the flood …

Sars Surveillance During Emergency Public Health Response, United States, March-July 2003, Stephanie J. Schrag, John T. Brooks, Chris Van Beneden, Umesh D. Parashar, Patricia M. Griffin, Larry J. Anderson, William J. Bellini, Robert F. Benson, Dean D. Erdman, Alexander Klimov, Thomas G. Ksiazek, Teresa C. T. Peret, Deborah F. Talkington, W. Lanier Thacker, Maria L. Tondella, Jacquelyn S. Sampson, Allen W. Hightower, Dale F. Nordenberg, Brian D. Plikaytis, Ali S. Khan, Nancy E. Rosenstein, Tracee A. Treadwell, Cynthia G. Whitney, Anthony E. Fiore, Tonji M. Durant, Joseph F. Perz, Annemarie Wasley, Daniel Feikin, Joy L. Herndon, William A. Bower, Barbara W. Klibourn, Deborah A. Levy, Victor G. Coronado, Joanna Buffington, Clare A. Dykewicz, Rima F. Khabbaz, Mary E. Chamberland

Journal Articles: Epidemiology

In response to the emergence of severe acute respiratory syndrome (SARS), the United States established national surveillance using a sensitive case definition incorporating clinical, epidemiologic, and laboratory criteria. Of 1,460 unexplained respiratory illnesses reported by state and local health departments to the Centers for Disease Control and Prevention from March 17 to July 30, 2003, a total of 398 (27%) met clinical and epidemiologic SARS case criteria. Of these, 72 (18%) were probable cases with radiographic evidence of pneumonia. Eight (2%) were laboratory-confirmed SARS-coronavirus (SARS-CoV) infections, 206 (52%) were SARS-CoV negative, and 184 (46%) had undetermined SARS-CoV status because of …

Surveillance For Waterborne-Disease Outbreaks Associated With Drinking Water--United States, 2001-2002, Brian G. Blackburn, Gunther F. Craun, Jonathan S. Yoder, Vincent Hill, Rebecca L. Calderon, Nora Chen, Sherline H. Lee, Deborah A. Levy, Michael J. Beach

Journal Articles: Epidemiology

PROBLEM/CONDITION: Since 1971, CDC, the U.S. Environmental Protection Agency, and the Council of State and Territorial Epidemiologists have maintained a collaborative surveillance system for collecting and periodically reporting data related to occurrences and causes of waterborne-disease outbreaks (WBDOs). This surveillance system is the primary source of data concerning the scope and effects of waterborne disease outbreaks on persons in the United States.

REPORTING PERIOD COVERED: This summary includes data on WBDOs associated with drinking water that occurred during January 2001-December 2002 and on three previously unreported outbreaks that occurred during 2000.

DESCRIPTION OF SYSTEM: Public health departments in the states, …

Surveillance For Waterborne-Disease Outbreaks Associated With Recreational Water--United States, 2001-2002, Jonathan S. Yoder, Brian G. Blackburn, Gunther F. Craun, Vincent Hill, Deborah A. Levy, Nora Chen, Sherline H. Lee, Rebecca L. Calderon, Michael J. Beach

Journal Articles: Epidemiology

PROBLEM/CONDITION: Since 1971, CDC, the U.S. Environmental Protection Agency, and the Council of State and Territorial Epidemiologists have maintained a collaborative surveillance system for collecting and periodically reporting data related to occurrences and causes of waterborne-disease outbreaks (WBDOs) related to drinking water; tabulation of recreational water-associated outbreaks was added to the surveillance system in 1978. This surveillance system is the primary source of data concerning the scope and effects of waterborne disease outbreaks on persons in the United States.

REPORTING PERIOD COVERED: This summary includes data on WBDOs associated with recreational water that occurred during January 2001-December 2002 and on …

Temporal Stability And Geographic Variation In Cumulative Case Fatality Rates And Average Doubling Times Of Sars Epidemics, Alison P. Galvani, Xiudong Lei, Nicholas P. Jewell

U.C. Berkeley Division of Biostatistics Working Paper Series

We analyze temporal stability and geographic trends in cumulative case fatality rates and average doubling times of severe acute respiratory syndrome (SARS). In part, we account for correlations between case fatality rates and doubling times through differences in control measures. We discuss factors that may alter future estimates of case fatality rates. We also discuss reasons for heterogeneity in doubling times among countries and the implications for the control of SARS in different countries and parameterization of epidemic models.

Application Of The Traditional Epidemiological Model To Predict Occupational Injury Rates In Manufacturing Industries, Gary A. Morris

Health Services Research Dissertations

This study was designed to test the usefulness of the Traditional Epidemiological Model of disease causation in modeling occupational injury rates and the presence of occupational illness in the manufacturing industry. More specifically, this research involved use of the agent, host, and environment constructs of the Traditional Epidemiological Model to examine the effects of five environmental-related workplace health and safety practices on occupational injury and illness. Data from the National Occupational Exposure Survey (NOES), conducted by the National Institute for Occupational Safety and Health (NIOSH) in 1981–1983, were used to ascertain the presence of specific workplace characteristics and to calculate …

Current Status Data: Review, Recent Developments And Open Problems, Nicholas P. Jewell, Mark J. Van Der Laan

U.C. Berkeley Division of Biostatistics Working Paper Series

Researchers working with survival data are by now adept at handling issues associated with incomplete data, particular those associated with various forms of censoring. An extreme form of interval censoring, known as current status observation, refers to situations where the only available information on a survival random variable T is whether or not T exceeds a random independent monitoring time C. This article contains a brief review of the extensive literature on the analysis of current status data, discussing the implications of response-based sampling on these methods. The majority of the paper introduces some recent extensions of these ideas to …