Geographic Analysis

Immigrants and refugees are required to undergo tuberculosis (TB) screening before entering the United States (US)(1). Nearly 700 overseas panel physicians designated by the US Department of State, perform these screenings (2). Over 450,000 new immigrants and nearly 80,000 refugees arrive in the US each year with their medical documentation (3). Those with culture positive or smear positive TB are treated prior to arrival in the US; those with radiographic or symptomatic TB but negative smears and culture may enter the US with Class B TB(4). After arrival, CDC's Electronic Disease Notification system (EDN) notifies the health departments of the results of overseas examinations.

Objective

To conduct preliminary assessment of the US destination locations among newly arriving immigrants and refugees with tuberculosis classifications

This report describes an exploratory analysis of the 2009-2010 Zimbabwe measles outbreak based on data publicly available in the World Health Organization's Zimbabwe cholera epidemiological bulletin archive. As of December 12th 2010, the outbreak appears to have ended after it is suspected to have caused 13,783 infections, 693 of those being confirmed IgM positive, and 631 deaths.

Objective

To systematically organize the World Health Organization data on the 2010 measles outbreak in Zimbabwe. To perform a post-hoc exploratory analysis to understand how the outbreak spread geographically and evaluate the effectiveness of a mass vaccination campaign.

Extreme heat events over the past 30 years have resulted in unprecedented increase in the numbers of heat-related morbidity and mortality across the world (1-3). During the same time frame, Houston residents has experienced three of the hottest summers on record since 1889, with 2011 being the hottest summer on record (4). Therefore, preparing for extreme heat events and monitoring their effects on public health is a vital role for the Houston Department of Health and Human Services (HDHHS). Since heat-related illnesses are not a reportable condition in the state of Texas, HDHHS authorities rely on other sources to provide information on the impact of heat on the population. HDHHS is currently able to monitor emergency departments (ED) visits across the Houston metropolitan area, Harris County, and the surrounding jurisdictions by using a syndromic surveillance system called Real-time Outbreak Disease Surveillance (RODS). The RODS system collects de-identified patient data that consists of their chief complaint and basic demographics (e.g. age, sex, zip code). This study is aimed at evaluating the ability of RODS to detect heat-related illnesses during heat event of the years 2009-2012 as well as identifying the areas of Houston that had the highest incidence of heat-related morbidity.

Objective

To evaluate the ability of a syndromic surveillance system to detect heat-related illnesses during a heat wave in Houston and to identify areas in Houston that requires additional resources to prevent heat-related illnesses.

The Houston Department of Health Department of Health and Human Services (HDHHS) monitors emergency departments (ED) chief complaints across the Houston metropolitan area, Harris County, and the surrounding jurisdictions by Real-time Outbreak Disease Surveillance (RODS). The influenza-like illnesses (ILI) data is collected by sentinel surveillance provider network of 12 physicians and RODS, an electronic syndromic surveillance database consisting of about 30 EDs in metropolitan Houston. Previous research indicates that there is a relationship between new HIV diagnoses and neighborhood poverty. However, there is limited research on health disparity to investigate the association between influenza-like illnesses (ILI) and social determinants of health (SDH), such as poverty.

Objective

To investigate the association between social determinants of health and influenza-like illnesses in Houston/Harris County and to identify neighborhoods for targeted surveillance or interventions.

In this study, we compare two methods of generating grid points to enable efficient geographic cluster detection when the original geographical data are prohibitively numerous. One method generates uniform grid points, and the other employs quad trees to generate non-uniform grid points. We observe differences in the results of the spatial scan approach to cluster detection for both of these grid generation schemes. In both our simulated experiment, and our analysis of real data, the grid generation schemes produce different results. Generally speaking, the quad tree scheme is more sensitive to detecting high resolution spatial clusters than the uniform scheme. The quad tree grid point scheme may be a useful alternative to the uniform (and other) grid point generation schemes when it is important to set up a surveillance system sensitive to clusters at unspecified spatial resolutions. The quad tree grid scheme may also be useful in a number of other geographic surveillance applications.

Surveillance of individual data streams is a well-accepted approach to monitor community incidence of infectious diseases such as influenza, and to enable timely detection of outbreaks so that control measures can be applied. However the performance of alerts may be improved by simultaneously monitor a variety of data sources, or multiple streams (eg from different geographic locations) of the same type, rather than monitoring only aggregate data. Rates of influenza-like illness in subtropical settings typically show greater variability than in temperate regions.

Objective

This paper describes the use of time series models for simultaneous monitoring of multiple streams of influenza surveillance data.

The development of a real time surveillance system for Forces on duty areas is one of the 5 initiatives of the November 2002 Prague’s NATO meeting. The French Military Health Service has decided to implement a military demonstrator within Forces in operations in a tropical area. This military prototype has three main objectives : i) to study the feasability of real time surveillance system within Forces in operations ii) to evaluate the benefit of such a system and iii) to develop a interoperable system for NATO. This French real time system has been developped by a multidisciplinary team, with military people but also with civilian experts from Pasteur Institute and Mediterranean University of Marseille.

Objective

This paper describes the new real time surveillance system, which has been installed within the French Forces in French Guiana.

On August 29, 2005, Hurricane Katrina made landfall just east of New Orleans, LA at 6:10AM CST and again at the LA/MS border at 10:00AM CST as a Category 3 hurricane, causing mass destruction along their coastlines. The devastation in LA and MS forced many residents to evacuate. Outside of the hurricane affected areas of LA, MS, and AL, GA received the second largest number of evacuees (approximately 125,000).

Objective

To describe the victims of Hurricane Katrina who evacuated to GA and to assess their impact on emergency departments enrolled in GA’s syndromic surveillance system.