The biological attacks with powders containing Bacillus anthracis sent through the mail during September and October 2001 led to unprecedented public health and law enforcement investigations, which involved thousands of investigators from federal, state, and local agencies. Following recognition of the first cases of anthrax in Florida in early October 2001, investigators from Centers for Disease Control and Prevention (CDC) and the Federal Bureau of Investigation (FBI) were mobilized to assist investigators from state and local public health and law enforcement agencies. Although public health and criminal investigations have been conducted in concert in the past, the response to the anthrax attacks required close collaboration because of the immediate and ongoing threat to public safety. We describe the collaborations between CDC and FBI during the investigation of the 2001 anthrax attacks and highlight the challenges and successes of public health and law enforcement collaborations in general.
police power; anthrax; quarantine; bioterrorism response; Bacillus anthracis; law; criminal investigation; Federal Bureau of Investigation
After reports of the intentional release of Bacillus anthracis in the United States, epidemiologists, laboratorians, and clinicians around the world were called upon to respond to widespread political and public concerns. To respond to inquiries from other countries regarding anthrax and bioterrorism, the Centers for Disease Control and Prevention established an international team in its Emergency Operations Center. From October 12, 2001, to January 2, 2002, this team received 130 requests from 70 countries and 2 territories. Requests originated from ministries of health, international organizations, and physicians and included subjects ranging from laboratory procedures and clinical evaluations to assessments of environmental and occupational health risks. The information and technical support provided by the international team helped allay fears, prevent unnecessary antibiotic treatment, and enhance laboratory-based surveillance for bioterrorism events worldwide.
anthrax; bioterrorism; international; Bacillus anthracis
In the wake of the September 11, 2001, attacks and the subsequent anthrax scare, there is growing concern about the United States' vulnerability to terrorist use of Weapons of Mass Destruction (WMD). As part of ongoing preparation for this terrible reality, many jurisdictions have been conducting simulated terrorist incidents to provide training for the public safety community, hospitals, and public health departments. As an example of this national effort to improve domestic preparedness for such events, a large scale, multi-jurisdictional chemical weapons drill was conducted in Cincinnati, Ohio, on May 20, 2000. This drill depicted the components of the early warning system for hospitals and public health departments, the prehospital medical response to terrorism. Over the course of the exercise, emergency medical services personnel decontaminated, triaged, treated, and transported eighty-five patients. Several important lessons were learned that day that have widespread applicability to health care delivery systems nationwide, especially in the areas of decontamination, triage, on-scene medical care, and victim transportation. As this training exercise helped Cincinnati to prepare for dealing with future large scale WMD incidents, such drills are invaluable preparation for all communities in a world increasingly at risk from terrorist attacks.
Following the 9/11 terrorist attacks, SET Environmental, Inc., a Chicago-based environmental and hazardousmaterials management company received a large number of suspicious powders for analysis.
Samples of powders were submitted to SET for anthrax screening and/or unknown identification (UI). Anthrax screening was performed on-site using a ruggedized analytical pathogen identification device (R.A.P.I.D.) (Idaho Technologies, Salt Lake City, UT). UI was performed at SET headquarters (Wheeling, IL) utilizing a combination of wet chemistry techniques, infrared spectroscopy, and gas chromatography/mass spectroscopy. Turnaround time was approximately 2–3 hours for either anthrax or UI.
Between October 10, 2001 and October 11, 2002, 161 samples were analyzed. Of these, 57 were for anthrax screening only, 78 were for anthrax and UI, and 26 were for UI only. Sources of suspicious powders included industries (66%), U.S. Postal Service (19%), law enforcement (9%), and municipalities (7%). There were 0/135 anthrax screens that were positive.
There were no positive anthrax screens performed by SET in the Chicago area following the post-9/11 anthrax scare. The only potential biological or chemical warfare agent identified (cyanide) was provided by law enforcement. Rapid anthrax screening and identification of unknown substances at the scene are useful to prevent costly interruption of services and potential referral for medical evaluation.
anthrax; suspicious powders; field testing of powders; weapons of mass destruction
The recent public health risks arising from bioterrorist threats and outbreaks of infectious diseases like SARS (Severe Acute Respiratory Syndrome) highlight the challenges of effectively communicating accurate health information to an alarmed public.
To evaluate use of the Internet in accessing information related to the anthrax scare in the United States in late 2001, and to strategize about the most effective use of this technology as a communication vehicle during times of public health crises.
A paper-based survey to assess how individuals obtained health information relating to bioterrorism and anthrax during late 2001.We surveyed 500 randomly selected patients from two ambulatory primary care clinics affiliated with the Brigham and Women's Hospital in Boston, Massachusetts.
The response rate was 42%. While traditional media provided the primary source of information on anthrax and bioterrorism, 21% (95% CI, 15% - 27%) of respondents reported searching the Internet for this information during late 2001. Respondents reported trusting information from physicians the most, and information from health websites slightly more than information from any traditional media source. Over half of those searching the Internet reported changing their behavior as a result of information found online.
Many people already look to the Internet for information during a public health crisis, and information found online can positively influence behavioral responses to such crises. However, the potential of the Internet to convey accurate health information and advice has not yet been realized. In order to enhance the effectiveness of public-health communication, physician practices could use this technology to pro-actively e-mail their patients validated information. Still, unless Internet access becomes more broadly available, its benefits will not accrue to disadvantaged populations.
bioterrorism; public health; communication; electronic mail; inequality; behavior
Public health situational awareness is contingent upon timely, comprehensive and accurate information from clinical systems. Ad-hoc models for sending non-standard clinical information directly to public health are inefficient and increasingly unsustainable. Information sharing models that leverage Health Information Exchanges (HIEs) are emerging. HIEs standardize, aggregate and streamline information sharing among data partners, including public health stakeholders, and HIE has supported public health practice in Indiana for more than 10 years. To accelerate nationwide adoption of HIE-supported situational awareness processes, the CDC awarded three HIEs across the nation, including Indiana, New York and Washington/Idaho. The Indiana partners included Indiana University School of Medicine, Regenstrief Institute, Indiana Health Information Exchange, Indiana State Department of Health, Health & Hospital Corporation of Marion County, and Children’s Hospital Boston. Activities included augmenting biosurveillance processes, enabling bi-directional communication, enhancing automated detection of notifiable conditions, and demonstrating technological advances at national forums. HIE transactions destined for public health were enhanced with standardized clinical vocabulary and more complete physician contact information. During the 2009 H1N1 flu outbreak, the HIE delivered targeted public health broadcast messages to providers in Marion County, Indiana. We will review the partnership characteristics, activities, accomplishments and future directions for our health information exchange.
health information exchange; situational awareness; biosurveillance; syndromic surveillance; influenza
We developed competencies for applied epidemiologic practice by using a process that is based on existing competency frameworks, that engages professionals in academic and applied epidemiology at all governmental levels (local, state, and federal), and that provides ample opportunity for input from practicing epidemiologists throughout the U.S.
The model set of core public health competencies, consisting of eight core domains of public health practice, developed in 2001 by the Council on Linkages Between Academia and Public Health Practice, were adopted as the foundation of the Competencies for Applied Epidemiologists in Governmental Public Health Agencies (AECs). A panel of experts was convened and met over a period of 20 months to develop a draft set of AECs. Drafts were presented at the annual meetings of the Council of State and Territorial Epidemiologists (CSTE) and the American Public Health Association. Input and comments were also solicited from practicing epidemiologists and 14 national organizations representing epidemiology and public health.
In all, we developed 149 competency statements across the eight domains of public health practice and four tiers of applied epidemiologic practice. In addition, sub- and sub-subcompetency statements were developed to increase the document's specificity. During the process, >800 comments from all governmental and academic levels and tiers of epidemiology practice were considered for the final statements.
The AECs are available for use in improving the training for and skill levels of practicing applied epidemiologists and should also be useful for educators, employers, and supervisors. Both CDC and CSTE plan to evaluate their implementation and usefulness in providing information for future competency development.
The Florida Center for Public Health Preparedness in the University of South Florida College of Public Health and the Florida Department of Health (FDOH) collaborated to design, develop, and deliver two competency-based epidemiology training programs aimed at increasing the epidemiologic preparedness and response capability of the FDOH workforce. They were also designed to meet the requirements of the National Incident Management System and recommendations or needs identified in national studies. The basis for the trainings is an epidemiology competency set developed by the Northwest Center for Public Health Practice at the University of Washington School of Public Health and Community Medicine. The target audiences for the two trainings are non-epidemiologists or practicing epidemiologists who have relatively little formal education in epidemiology. Both courses have online as well as onsite modules. Alternate tabletop exercises have been completed and delivered for anthrax and plague. Both trainings require participant demonstration of skills. The trainings have been well received, appear to be effective, and are used to credential members of Florida's epidemiology strike teams.
After public notification of confirmed cases of bioterrorism-related anthrax, the Centers for Disease Control and Prevention’s Emergency Operations Center responded to 11,063 bioterrorism-related telephone calls from October 8 to November 11, 2001. Most calls were inquiries from the public about anthrax vaccines (58.4%), requests for general information on bioterrorism prevention (14.8%), and use of personal protective equipment (12.0%); 882 telephone calls (8.0%) were referred to the state liaison team for follow-up investigation. Of these, 226 (25.6%) included reports of either illness clinically confirmed to be compatible with anthrax or direct exposure to an environment known to be contaminated with Bacillus anthracis. The remaining 656 (74.4%) included no confirmed illness but reported exposures to “suspicious” packages or substances or the receipt of mail through a contaminated facility. Emergency response staff must handle high call volumes following suspected or actual bioterrorist attacks. Standardized health communication protocols that address contact with unknown substances, handling of suspicious mail, and clinical evaluation of suspected cases would allow more efficient follow-up investigations of clinically compatible cases in high-risk groups.
anthrax; bioterrorism; triage; Centers for Disease Control and Prevention
During the 2001 anthrax attacks, public health agencies faced operational and communication decisions about the use of antibiotic prophylaxis and the anthrax vaccine with affected groups, including postal workers. This communication occurred within an evolving situation with incomplete and uncertain data. Guidelines for prophylactic antibiotics changed several times, contributing to confusion and mistrust. At the end of 60 days of taking antibiotics, people were offered an additional 40 days' supply of antibiotics, with or without the anthrax vaccine, the former constituting an investigational new drug protocol. Using data from interviews and focus groups with 65 postal workers in 3 sites and structured interviews with 16 public health professionals, this article examines the challenges for public health professionals who were responsible for communication with postal workers about the vaccine. Multiple factors affected the response, including a lack of trust, risk perception, disagreement about the recommendation, and the controversy over the military's use of the vaccine. Some postal workers reacted with suspicion to the vaccine offer, believing that they were the subjects of research, and some African American workers specifically drew an analogy to the Tuskegee syphilis study. The consent forms required for the protocol heightened mistrust. Postal workers also had complex and ambivalent responses to additional research on their health. The anthrax attacks present us with an opportunity to understand the challenges of communication in the context of uncertain science and suggest key strategies that may improve communications about vaccines and other drugs authorized for experimental use in future public health emergencies.
The spread of infectious agents through the mail has concerned public health officials for 5 centuries. The dissemination of anthrax spores in the US mail in 2001 was a recent example. In 1901, two medical journals reported outbreaks of smallpox presumably introduced by letters contaminated with variola viruses. The stability and infectivity of the smallpox virus are reviewed from both a historical (anecdotal) perspective and modern virologic studies. Bubonic plague was the contagious disease that led to quarantines as early as the 14th century in port cities in southern Europe. Later, smallpox, cholera, typhus, and yellow fever were recognized as also warranting quarantine measures. Initially, attempts were made to decontaminate all goods imported from pestilential areas, particularly mail. Disinfection of mail was largely abandoned in the early 20th century with newer knowledge about the spread and stability of these 5 infectious agents.
bioterrorism; Decontamination; Disinfection; Lazarettos; Osler; quarantine; smallpox; Variola; Viral stability; Mail
To allow public health officials to uniformly define, collect, and report chronic disease data, Indicators for Chronic Disease Surveillance was released by the Council of State and Territorial Epidemiologists in 1999. This publication provided standard definitions for 73 indicators developed by epidemiologists and chronic disease program directors at the state and federal levels. The indicators were selected because of their importance to public health and the availability of state-level data. This report describes the latest revisions to the chronic disease indicators published in 2004. The revised set of 92 indicators includes 24 for cancer; 15 for cardiovascular disease; 11 for diabetes; 7 for alcohol; 5 each for nutrition and tobacco; 3 each for oral health, physical activity, and renal disease; and 2 each for asthma, osteoporosis, and immunizations. The remaining 10 indicators cover such overarching conditions as poverty, education, and life expectancy. Although multiple states have used the indicators, wider adoption depends on increased epidemiology capacity at the state level and improved access to surveillance data.
Using the 2003 National Survey of Children’s Health (NSCH) sponsored by the federal Maternal and Child Health Bureau, we calculated prevalence estimates of eczema nationally and for each state among a nationally representative sample of 102,353 children 17 years of age and under. Our objective was to determine the national prevalence of eczema/atopic dermatitis in the United States pediatric population and to further examine geographic and demographic associations previously reported in other countries. Overall, 10.7% of children were reported to have a diagnosis of eczema in the last 12 months. Prevalence ranged from 8.7% to 18.1% between states and districts, with the highest prevalence reported in many of the East Coast states, as well as Nevada, Utah, and Idaho. After adjusting for confounders, metropolitan living was found to be a significant factor in predicting a higher disease prevalence with an OR of 1.67 (95% confidence interval of 1.19-2.35, p=0.008). Black race (OR 1.70, p=0.005) and education level in the household greater than high school (OR 1.61, p=0.004) were also significantly associated with a higher prevalence of eczema. The wide range of prevalence suggests social or environmental factors may influence disease expression.
We used unpublished reports, published manuscripts, and communication with investigators to identify and summarize 49 anthrax-related epidemiologic field investigations conducted by the Centers for Disease Control and Prevention from 1950 to August 2001. Of 41 investigations in which Bacillus anthracis caused human or animal disease, 24 were in agricultural settings, 11 in textile mills, and 6 in other settings. Among the other investigations, two focused on building decontamination, one was a response to bioterrorism threats, and five involved other causes. Knowledge gained in these investigations helped guide the public health response to the October 2001 intentional release of B. anthracis, especially by addressing the management of anthrax threats, prevention of occupational anthrax, use of antibiotic prophylaxis in exposed persons, use of vaccination, spread of B. anthracis spores in aerosols, clinical diagnostic and laboratory confirmation methods, techniques for environmental sampling of exposed surfaces, and methods for decontaminating buildings.
anthrax; Bacillus anthracis; bacterial infections; disease outbreaks; public health; bioterrorism; Centers for Disease Control and Prevention (U.S.); historical article (publication type); zoonoses
Health emergency planning for preparedness and response against acts of terrorism, including the malfeasant threat or actual release of biological agents designed to harm others, has assumed a higher level of concern for most western nations, including Canada, following the explosive attacks in the United States on September 11, 2001. These terrorist attacks were followed by an outbreak of anthrax infections. The Bacillus anthracis spores in these attacks were dispersed by using regular postal services in the United States. In addition to the unsettling sense of social vulnerability that resulted from these attacks, a greater appreciation that the integration of public health, emergency health and social services with security activities was required to fully address the need to protect the health and other interests of the citizens. Collaborative work among regional, provincial, territorial, federal and international authorities within these domains is emerging as an effective response to the risk management of bioterrorism. The following is a brief description of the health framework for preparedness and response, and the biological agents of major concern in terrorism.
Bioterrorism; Health emergency
In 2003, 11 public health epidemiologists were placed in North Carolina's largest hospitals to enhance communication between public health agencies and healthcare systems for improved emergency preparedness. We describe the specific services public health epidemiologists provide to local health departments, the North Carolina Division of Public Health, and the hospitals in which they are based, and assess the value of these services to stakeholders.
We surveyed and/or interviewed public health epidemiologists, communicable disease nurses based at local health departments, North Carolina Division of Public Health staff, and public health epidemiologists' hospital supervisors to 1) elicit the services provided by public health epidemiologists in daily practice and during emergencies and 2) examine the value of these services. Interviews were transcribed and imported into ATLAS.ti for coding and analysis. Descriptive analyses were performed on quantitative survey data.
Public health epidemiologists conduct syndromic surveillance of community-acquired infections and potential bioterrorism events, assist local health departments and the North Carolina Division of Public Health with public health investigations, educate clinicians on diseases of public health importance, and enhance communication between hospitals and public health agencies. Stakeholders place on a high value on the unique services provided by public health epidemiologists.
Public health epidemiologists effectively link public health agencies and hospitals to enhance syndromic surveillance, communicable disease management, and public health emergency preparedness and response. This comprehensive description of the program and its value to stakeholders, both in routine daily practice and in responding to a major public health emergency, can inform other states that may wish to establish a similar program as part of their larger public health emergency preparedness and response system.
State and local health departments continue to face unprecedented challenges in preparing for, recognizing, and responding to threats to the public’s health. The attacks of 11 September 2001 and the ensuing anthrax mailings of 2001 highlighted the public health readiness and response hurdles posed by intentionally caused injury and illness. At the same time, recent natural disasters have highlighted the need for comparable public health readiness and response capabilities. Public health readiness and response activities can be conceptualized similarly for intentional attacks, natural disasters, and human-caused accidents. Consistent with this view, the federal government has adopted the all-hazards response model as its fundamental paradigm. Adoption of this paradigm provides powerful improvements in efficiency and efficacy, because it reduces the need to create a complex family of situation-specific preparedness and response activities. However, in practice, public health preparedness requires additional models and tools to provide a framework to better understand and prioritize emergency readiness and response needs, as well as to facilitate solutions; this is particularly true at the local health department level. Here, we propose to extend the use of the Haddon matrix—a conceptual model used for more than two decades in injury prevention and response strategies—for this purpose.
dirty bombs; emergency; Haddon matrix; injury prevention; preparedness; public health; readiness; response; SARS; terrorism
Inappropriate use of antibiotics by individuals worried about biological agent exposures during bioterrorism events is an important public health concern. However, little is documented about the extent to which individuals with self-identified risk of anthrax exposure approached physicians for antimicrobial prophylaxis during the 2001 bioterrorism attacks in the United States.
We conducted a telephone survey of randomly selected members of the Pennsylvania Chapter of the American College of Emergency Physicians to assess patients' request for and emergency physicians' prescription of antimicrobial agents during the 2001 anthrax attacks.
Ninety-seven physicians completed the survey. Sixty-four (66%) respondents had received requests from patients for anthrax prophylaxis; 16 (25%) of these physicians prescribed antibiotics to a total of 23 patients. Ten physicians prescribed ciprofloxacin while 8 physicians prescribed doxycycline.
During the 2001 bioterrorist attacks, the majority of the emergency physicians we surveyed encountered patients who requested anthrax prophylaxis. Public fears may lead to a high demand for antibiotic prophylaxis during bioterrorism events. Elucidation of the relationship between public health response to outbreaks and outcomes would yield insights to ease burden on frontline clinicians and guide strategies to control inappropriate antibiotic allocation during bioterrorist events.
In 1991, most physicians in Minnesota and Wisconsin managed patients concerns about anthrax without dispensing prophylactic antimicrobial agents.
Media reports suggested increased public demand for anthrax prophylaxis after the intentional anthrax cases in 2001, but the magnitude of anthrax-related prescribing in unaffected regions was not assessed. We surveyed a random sample of 400 primary care clinicians in Minnesota and Wisconsin to assess requests for and provision of anthrax-related antimicrobial agents. The survey was returned by 239 (60%) of clinicians, including 210 in outpatient practice. Fifty-eight (28%) of those in outpatient practice received requests for anthrax-related antimicrobial agents, and 9 (4%) dispensed them. Outpatient fluoroquinolone use in both states was also analyzed with regression models to compare predicted and actual use in October and November 2001. Fluoroquinolone use as a proportion of total antimicrobial use was not elevated, and anthrax concerns accounted for an estimated 0.3% of all fluoroquinolone prescriptions. Most physicians in Minnesota and Wisconsin managed anthrax-related requests without dispensing antimicrobial agents.
research, anthrax, fluoroquinolone, prophylaxis; drug resistance; bioterrorism
A high rate of turnover of professional personnel in a clinic is disruptive to patient care and organizational stability as well as to the individual clinician. The turnover rate for clinicians (physicians, nurse practitioners, and physician assistants) working in neighborhood health centers (NHCs) is considerably higher than that for clinicians in other forms of practices. All 10 of the neighborhood health centers in HEW (Department of Health, Education, and Welfare--now the Department of Health and Human Services) Region X (Alaska, Idaho, Washington, and Oregon) that offered a full range of medical services provided information about the clinicians that they had employed since their inception. One hundred and one clinicians were surveyed about their work experience. The vast majority of those clinicians who had left a neighborhood health center remained in the community; they cited organizational issues as being at the heart of their dissatisfaction with the centers. Clinicians who began work during the initiation of a clinic remained significantly longer. The results suggest the immediate need for a strategy directed at the smooth organizational evolution of each NHC right from its inception.
To describe radiation-related exposures of potential public health significance reported to the National Poison Data System (NPDS).
For radiological incidents, collecting surveillance data can identify radiation-related public health significant incidents quickly and enable public health officials to describe the characteristics of the affected population and the magnitude of the health impact which in turn can inform public health decision-making. A survey administered by the Council of State and Territorial Epidemiologists (CSTE) to state health departments in 2010 assessed the extent of state-level planning for surveillance of radiation-related exposures and incidents: 70%–84% of states reported minimal or no planning completed. One data source for surveillance of radiological exposures and illnesses is regional poison centers (PCs), who receive information requests and reported exposures from healthcare providers and the public. Since 2010, the Centers for Disease Control and Prevention (CDC) and the American Association of Poison Control Centers (AAPCC) have conducted ongoing surveillance for exposures to radiation and radioactive materials reported from all 57 United States (US) PCs to NPDS, a web-based, national PC reporting database and surveillance system.
We collaborated with the American Association of Poison Control Centers (AAPCC), Poisindex® and Thomson Reuters Healthcare to develop an improved coding system for tracking radiation-related exposures reported to US PCs during 2011 and trained PC staff on its usage. We reviewed NPDS data from 1 September 2010 – 30 June 2012 for reported exposures to pharmaceutical or nonpharmaceutical radionuclides; ionizing radiation; radiological or nuclear weapons; or X-ray, alpha, beta, gamma, or neutron radiation. CDC medical toxicology and epidemiology staff reviewed each reported exposure to determine whether it was of potential public health concern (e.g. exposures associated with an ongoing public health emergency, several reported exposures clustered in space and time). When further information was needed to classify the potential public health importance of a call, CDC and AAPCC staff contacted the regional PC where each call originated. When exposures were spatially and temporally clustered, we reviewed news stories in the public media for evidence of an associated radiation incident.
Of 419 exposures reported during the study period, 25 were associated with a radiation-related incident. Of these, 4 were related to an exposure to x-ray radiation from an industrial radiography incident, 11 were related to a transportation accident involving potential contamination with radioactive material, and 10 were related to the Fukushima Daiichi Japan nuclear reactor disaster. Public health, hazardous materials, or hospital radiation safety staff were involved in responding to each of these events. We also identified 26 reported exposures associated with a regional radiation anti-terrorism exercise. The reported exposures were followed-up and removed from analysis once we determined they were part of the exercise. The remaining (n=368; 88%) were either requests for information, confirmed non-exposures, or exposures deemed unrelated or non-significant.
The capability to monitor self- or clinician-reported exposures to radiation and radioactive materials is available in NPDS for state and local public health use in collaboration with their regional PC and may improve public health capacity to identify and respond to radiological emergencies. Next steps include testing the system’s capability to accurately classify and rapidly respond to a cluster of calls to PCs reporting radiation exposures associated with a “dirty bomb” exercise during July, 2012.
Surveillance; Poison center; radiation
In January 2001 the Pew Environmental Health Commission called for the creation of a coordinated public health system to prevent disease in the United States by tracking and combating environmental health threats. In response, the Centers for Disease Control and Prevention initiated the Environmental Public Health Tracking (EPHT) Program to integrate three distinct components of hazard monitoring and exposure and health effects surveillance into a cohesive tracking network. Uniform and acceptable data standards, easily understood case definitions, and improved communication between health and environmental agencies are just a few of the challenges that must be addressed for this network to be effective. The nascent EPHT program is attempting to respond to these challenges by drawing on a wide range of expertise from federal agencies, state health and environmental agencies, nongovernmental organizations, and the program’s academic Centers of Excellence. In this mini-monograph, we present innovative strategies and methods that are being applied to the broad scope of important and complex environmental public health problems by developing EPHT programs. The data resulting from this program can be used to identify areas and populations most likely to be affected by environmental contamination and to provide important information on the health and environmental status of communities. EPHT will develop valuable data on possible associations between the environment and the risk of noninfectious health effects. These data can be used to reduce the burden of adverse health effects on the American public.
environmental monitoring; environmental public health surveillance; information system integration; tracking
During the anthrax attack of 2001, the Florida Department of Health (FDOH) Bureau of Laboratories in Tampa received hundreds of isolates suspected of being Bacillus anthracis. None were confirmed to be B. anthracis since most isolates were motile and not even in the Bacillus cereus group. Although the sentinel laboratories now send fewer isolates to FDOH laboratories, should another attack occur the number of isolates submitted would likely increase dramatically, and this upsurge would seriously challenge personnel who are expected to be busy examining an increased number of environmental samples. We examined two selective and differential growth media and alternative motility methods that could be used to streamline the processing of suspicious isolates. Of 60 isolates previously sent to the FDOH laboratory, 56 were endospore-forming gram-positive rods and only 7 grew on mannitol-egg yolk-polymyxin B agar and/or the Anthracis chromogenic agar. Microscopic observation of early-log-phase growth (2 to 3 h) in a shaking broth was the best method to detect motility in 40 isolates that appeared nonmotile in the motility media investigated. One of these growth media and microscopic examination of shaken broth cultures can be used to show that an isolate is not B. anthracis before expensive molecular and antibody-based tests are performed. By doing so, costs could be reduced and analysis time shortened.
Anthrax is a soil-borne disease caused by the bacterium Bacillus anthracis and is considered a neglected zoonosis. In the country of Georgia, recent reports have indicated an increase in the incidence of human anthrax. Identifying sub-national areas of increased risk may help direct appropriate public health control measures. The purpose of this study was to evaluate the spatial distribution of human anthrax and identify environmental/anthropogenic factors associated with persistent clusters.
A database of human cutaneous anthrax in Georgia during the period 2000–2009 was constructed using a geographic information system (GIS) with case data recorded to the community location. The spatial scan statistic was used to identify persistence of human cutaneous anthrax. Risk factors related to clusters of persistence were modeled using a multivariate logistic regression. Areas of persistence were identified in the southeastern part of the country. Results indicated that the persistence of human cutaneous anthrax showed a strong positive association with soil pH and urban areas.
Anthrax represents a persistent threat to public and veterinary health in Georgia. The findings here showed that the local level heterogeneity in the persistence of human cutaneous anthrax necessitates directed interventions to mitigate the disease. High risk areas identified in this study can be targeted for public health control measures such as farmer education and livestock vaccination campaigns.
Anthrax is a zoonotic bacterial disease that occurs nearly worldwide. Despite a large number of countries reporting endemic anthrax, persistence of the disease appears to be associated with specific ecological factors related to soil composition and climatic conditions. Human cases are most often associated with handling infected livestock or contaminated meat and most cases are in cutaneous form (skin infections). Following the collapse of the Soviet Union, the country of Georgia has undergone major restructuring in land management and livestock handling and anthrax remains a serious public health risk. Few studies have evaluated the local spatial patterns of human anthrax. Here we identify areas on the landscape where human cutaneous anthrax persisted over the last decade. Persistence was found to be associated with both anthropogenic and environmental factors including soil pH and livestock density. These findings aid in the establishment of spatial baseline estimates of the disease and allow public health officials to adopt targeted anthrax control strategies, such as livestock vaccination campaigns and farmer education.
Early detection of outdoor aerosol releases of anthrax is an important problem. The Bayesian Aerosol Release Detector (BARD) is a system for detecting releases of aerosolized anthrax and characterizing them in terms of location, time and quantity. Modelling a population's exposure to aerosolized anthrax poses a number of challenges. A major difficulty is to accurately estimate the exposure level--the number of inhaled anthrax spores--of each individual in the exposed region. Partly, this difficulty stems from the lack of fine-grained data about the population under surveillance. To cope with this challenge, nearly all anthrax biosurveillance systems, including BARD, ignore the mobility of the population and assume that exposure to anthrax would occur at one's home administrative unit--an assumption that limits the fidelity of the model.
We employed commuting data provided by the U.S. Census Bureau to parameterize a commuting model. Then, we developed methods for integrating commuting into BARD's simulation and detection algorithms and conducted two studies to measure the effect. The first study (simulation study) was designed to assess how BARD's detection and characterization performance are impacted by incorporation of commuting in BARD's outbreak-simulation algorithm. The second study (detection study) was designed to measure the effect of incorporating commuting in BARD's outbreak-detection algorithm.
We found that failing to account for commuting in detection (when commuting is present in simulation) leads to a deterioration in BARD's detection and characterization performance that is both statistically and practically significant. We found that a simplified approach to accounting for commuting in detection--simplified to maintain tractability of inference--nearly fully restored both detection and characterization performance of BARD detector.
We conclude that it is important to account for commuting (and mobility in general) in BARD's simulation algorithm. Further, the proposed method for incorporating commuting in BARD's detection algorithm can successfully perform the necessary correction in the detection algorithm, while preserving BARD's practicality. In our future work, we intend to further study the problem of the trade-off between running time and accuracy of the computation in BARD's version that includes commuting and ultimately find the best such trade-off.