Kristen Pogreba-Brown

Are fecal indicator bacteria appropriate measures of recreational water risks in the tropics: A cohort study of beach goers in Brazil?

Regulating recreational water exposure to pathogens within the tropics is a major public health and economic concern. Although numerous epidemiological studies estimating the risk to recreational marine water exposure have been conducted since the 1950s, few studies have been done in the tropics. Furthermore, many have suggested that the use of fecal indicator bacteria for monitoring recreational water quality in temperate regions is not appropriate in the tropics. We analyzed a large cohort study of five beaches in Sao Paulo, Brazil, conducted during consecutive weekends in the summer of 1999 that estimated risk to water, sand, and food exposures. Enterococci and Escherichia coli concentrations were measured each day of the study. Elevated risks were estimated for both swimming (OR = 1.36 95% CI: 1.05-1.58) and sand contact (OR = 1.29 95% CI 1.05-1.58). A 1 log increase in enterococci concentration was associated with an 11% increase in risk (OR = 1.11 95% CI: 1.04-1.19). For E. coli a 1-log increase in concentration was associated with 19% increase in risk (OR = 1.19 95% CI: 1.14-1.28). Most countries with beaches in the tropics are lower or middle income countries (LMIC) and rely on tourism as a major source of income. We present data that suggests fecal indicator bacteria such as enterococci are an appropriate indicator of risk in tropical urban settings where contamination is coming from predominantly human sources. Additional studies in tropical settings could help inform and refine guidelines for safe use of recreational waters.

The Effect of Policy Changes on Hepatitis A Vaccine Uptake in Arizona Children, 1995-2008

Objective. In 1995, the first hepatitis A vaccines became available for use. At that time, Arizona had the highest hepatitis A incidence of all 50 states. During that same time period, the Arizona State Immunization Information System (ASIIS) was created to collect information on all immunizations given in the state. Four state-level hepatitis A vaccination policies were enacted according to Centers for Disease Control and Prevention recommendations and local initiatives from 1996 to 2005. Our primary objective was to assess the impact of these policies on vaccine uptake in children. Methods. Immunization records from ASIIS were used to calculate yearly coverage of children with at least one reported hepatitis A vaccination between 1995 and 2008. Proportions vaccinated were calculated by age group (12–23 months, 24–59 months, 5–9 years, 10–14 years, and 15–19 years) for three regions: Maricopa County; Apache and Navajo counties; and the remaining 12 Arizona counties, which were grouped as one to reflect different target groups for the four policies examined. We calculated percent changes from before and after each policy implementation. Results. Significantly different percent changes were detected among the three regions that related to the four policies implemented. Percent change in uptake was consistently higher in the regions that were targeted for that specific policy. Conclusions. Analysis of ASIIS data revealed a major effect of hepatitis A policy recommendations on vaccine uptake in Arizona. Targeting high-risk populations through vaccine recommendations and child care entry requirements was highly successful in achieving higher vaccination coverage.

Assessing risk factors of sporadic Campylobacter infection: a case-control study in Arizona.

Case-control studies of sporadic Campylobacter infections have predominately been conducted in non-Hispanic populations. In Arizona, rates of campylobacteriosis have been historically higher than the national average, with particularly high rates in Hispanics. In 2010, health departments and a state university collaborated to conduct a statewide case-control study to determine whether risk factors differ in an ethnically diverse region of the United States. Statistically significant risk factors in the final multivariate model were: eating cantaloupe [odds ratio (OR) 7·64], handling raw poultry (OR 4·88) and eating queso fresco (OR 7·11). In addition, compared to non-Hispanic/non-travellers, the highest risk group were Hispanic/non-travellers (OR 7·27), and Hispanic/travellers (OR 5·87, not significant). Results of this study suggest Hispanics have higher odds of disease, probably due to differential exposures. In addition to common risk factors, consumption of cantaloupe was identified as a significant risk factor. These results will inform public health officials of the varying risk factors for Campylobacter in this region.

Use of an online survey during an outbreak of clostridium perfringens in a retirement community - Arizona, 2012

CONTEXT An outbreak of gastrointestinal (GI) illness among retirement community residents was reported to the Maricopa County Department of Public Health. Online surveys can be useful for rapid investigation of disease outbreaks, especially when local health departments lack time and resources to perform telephone interviews. Online survey utility among older populations, which may lack computer access or literacy, has not been defined. OBJECTIVE To investigate and implement prevention measures for a GI outbreak and assess the utility of an online survey among retirement community residents. DESIGN A retrospective cohort investigation was conducted using an online survey distributed through the retirement community e-mail listserv; a follow-up telephone survey was conducted to assess computer literacy and Internet access. A case was defined as any GI illness occurring among residents during March 1-14, 2012. SETTING A barbecue in a retirement community of 3000 residents. PARTICIPANTS Retirement community residents. INTERVENTION Residents were directed to discard leftover food and seek health care for symptoms. A telephone survey was conducted to assess the utility of online surveys in this population. MAIN OUTCOME MEASURES Computer literacy and Internet access of retirement community residents. RESULTS Of 1000 residents on the listserv, 370 (37%) completed the online survey (mean age, 69.7 years; 60.6% women); 66 residents (17.8%) reported a GI illness after the barbecue, 63 (95.5%) reported diarrhea, and 5 (7.6%) reported vomiting. Leftover beef from an attendees refrigerator grew Clostridium perfringens. Of 552 residents contacted by telephone, 113 completed the telephone survey (mean age, 71.3 years; 63.3% women), 101 (89.4%) reported the ability to send e-mail, 82 (81.2%) checked e-mail daily, and 28 (27.7%) checked e-mail on a handheld device. The attack rate was 17.8% for online versus 2.7% for telephone respondents (P < .001). CONCLUSIONS This outbreak demonstrated the utility of an online survey to rapidly collect information and implement prevention measures among an older demographic.

Public Health Surveillance Strategies for Mass Gatherings: Super Bowl XLIX and Related Events, Maricopa County, Arizona, 2015.

Super Bowl XLIX took place on February 1, 2015, in Glendale, Arizona. In preparation for this event and associated activities, the Maricopa County Department of Public Health (MCDPH) developed methods for enhanced surveillance, situational awareness, and early detection of public health emergencies. Surveillance strategies implemented from January 22 to February 6, 2015, included enhanced surveillance alerts; animal disease surveillance; review of NFL clinic visits; syndromic surveillance for emergency room visits, urgent care facilities, and hotels; real-time onsite syndromic surveillance; all-hazards mortality surveillance; emergency medical services surveillance, review of poison control center reports; media surveillance; and aberration detection algorithms for notifiable diseases. Surveillance results included increased influenzalike illness activity reported from urgent care centers and a few influenza cases reported in the NFL clinic. A cyanide single event exposure was investigated and determined not to be a public health threat. Real-time field syndromic surveillance documented minor injuries at all events and sporadic cases of gastrointestinal and neurological (mostly headaches) disease. Animal surveillance reports included a cat suspected of carrying plague and tularemia and an investigation of highly pathogenic avian influenza in a backyard chicken flock. Laboratory results in both instances were negative. Aberration detection and syndromic surveillance detected an increase in measles reports associated with a Disneyland exposure, and syndromic surveillance was used successfully during this investigation. Coordinated enhanced epidemiologic surveillance during Super Bowl XLIX increased the response capacity and preparedness of MCDPH to make informed decisions and take public health actions in a timely manner during these mass gathering events.

Public health in the field and the emergency operations center: methods for implementing real-time onsite syndromic surveillance at large public events.

OBJECTIVE To develop an onsite syndromic surveillance system for the early detection of public health emergencies and outbreaks at large public events. METHODS As the third largest public health jurisdiction in the United States, Maricopa County Department of Public Health has worked with academic and first-response partners to create an event-targeted syndromic surveillance (EVENTSS) system. This system complements long-standing traditional emergency department-based surveillance and provides public health agencies with rapid reporting of possible clusters of illness. RESULTS At 6 high profile events, 164 patient reports were collected. Gastrointestinal and neurological syndromes were most commonly reported, followed by multisyndromic reports. Neurological symptoms were significantly increased during hot weather events. The interview rate was 2 to 7 interviews per 50 000 people per hour, depending on the ambient temperature. Discussion Study data allowed an estimation of baseline values of illness occurring at large public events. As more data are collected, prediction models can be built to determine threshold levels for public health response. CONCLUSIONS EVENTSS was conducted largely by volunteer public health graduate students, increasing the response capacity for the health department. Onsite epidemiology staff could make informed decisions and take actions quickly in the event of a public health emergency.

The Dicrotic Pulse: A Common, Non-Ominous Finding After the Ross Operation

We noted a dicrotic pulse in several patients following a Ross operation. Although the etiology of this unique arterial waveform is not completely understood, it has been reported as a sign of low cardiac output and a poor prognosis. We reviewed preoperative echocardiograms and postoperative radial arterial pressure tracings in 33 patients who underwent a Ross procedure between 2000 and 2004. We found a dicrotic pulse to occur commonly (20/33; 61%) following a Ross operation. Moderate to severe preoperative aortic insufficiency was present in 19/20 patients (95%) in whom a dicrotic pulse was noted and in only 3/13 (23%) who did not exhibit a postoperative dicrotic pulse (p < 0.001). A dicrotic pulse was not associated with an increased use of vasoactive infusions or longer hospitalization following the Ross operation. The dicrotic pulse should be recognized as a common postoperative finding in Ross patients that does not herald a delayed postoperative convalescence. The mechanism for a dicrotic pulse in these patients is speculative but may result from changes in vascular compliance secondary to chronic aortic insufficiency.

An Experiential Learning Exercise in Food-Borne Illness Outbreak Investigations: Bridging Education and Experience:

Conducting engaging experiential learning exercises is an exceptional strategy for teaching multidisciplinary teams of public health students. The objective of this article is to present an experiential student-driven exercise through a simulated food-borne outbreak. Through this process, students gain an understanding of the steps of an outbreak investigation, Incident Command Systems; identify and calculate appropriate measures of association; develop a questionnaire; and refine their communication techniques. This exercise is also unique in that it was codesigned by graduate teaching assistants who had previously taken the course. These targeted learning objectives created for students, and by students, allow for the development of peer-based training and also serve as a learning experience for student alumni. The authors provide all the needed teaching materials to provide an easy-to-follow guide for others to conduct similar exercises with their students.

Determining risk factors of a non-point source outbreak of Campylobacter cases using case-case and case-control studies.

Background: Investigating foodborne outbreaks is a resource and time-intensive process using traditional casecontrol methodology. The use of case-case studies in outbreak investigations is not well studied, although they require fewer resources to conduct and limit selection and recall bias. In this study we investigated a cluster of Campylobacter infections using almost simultaneous case-control and case-case studies to compare results from the two methodologies. Methods: In 2011 a significant increase in Campylobacter cases was detected in Pima County, AZ through routine surveillance. To determine potential sources of the outbreak we conducted two studies. The case-control study used randomly selected non-ill controls. The case-case study used historical surveillance data. Logistic regression analysis was used to determine risk factors for infection. Results: Statistically significant risk factors associated with disease differed by design with travel (OR=4.1), Hispanic (OR=4.5), and youth (OR=3.6) in the case-control and untreated water (OR=3.4) and fresh eggs (OR=2.5) in the case-case. Effect modification by travel was found for untreated water (OR=14.0 for travelers vs. OR=undefined for non-travelers) and eggs (OR=11.5 for travelers vs. OR=1.5 for non-travelers). Conclusions: Travel history, a commonly reported risk factor, is a distal part of the exposure pathway. These studies exposed the more proximal cause to be largely attributed to travelers who had exposure to untreated water and fresh eggs. Case-case methods were found to be useful in outbreak investigations of a foodborne illness. This outbreak is also an example where a student response team response with a local public health department.