Search

ObjectivesThe US Centers for Disease Control and Prevention (CDC)-funded Preparedness and Emergency Response Research Centers (PERRCs) conducted research from 2008 to 2015 aimed to improve the complex public health emergency preparedness and response (PHEPR) system. This paper summarizes PERRC studies that addressed the development and assessment of criteria for evaluating PHEPR and metrics for measuring their efficiency and effectiveness.MethodsWe reviewed 171 PERRC publications indexed in PubMed between 2009 and 2016. These publications derived from 34 PERRC research projects. We identified publications that addressed the development or assessment of criteria and metrics pertaining to PHEPR systems and describe the evaluation methods used and tools developed, the system domains evaluated, and the metrics developed or assessed.ResultsWe identified 29 publications from 12 of the 34 PERRC projects that addressed PHEPR system evaluation criteria and metrics. We grouped each study into 1 of 3 system domains, based on the metrics developed or assessed: (1) organizational characteristics (n = 9), (2) emergency response performance (n = 12), and (3) workforce capacity or capability (n = 8). These studies addressed PHEPR system activities including responses to the 2009 H1N1 pandemic and the 2011 tsunami, as well as emergency exercise performance, situational awareness, and workforce willingness to respond. Both PHEPR system process and outcome metrics were developed or assessed by PERRC studies.ConclusionsPERRC researchers developed and evaluated a range of PHEPR system evaluation criteria and metrics that should be considered by system partners interested in assessing the efficiency and effectiveness of their activities. Nonetheless, the monitoring and measurement problem in PHEPR is far from solved. Lack of standard measures that are readily obtained or computed at local levels remains a challenge for the public health preparedness field. (Disaster Med Public Health Preparedness. 2019;13:626-638)

Objectives The objective of our study was to assess whether state and local health staff participated in public health emergency preparedness research activities and what partner organizations they collaborated with on research. Study design This is a cross-sectional study. Methods Data were derived from a 2014 web-based survey of state, territorial, and local health departments conducted by the Centers for Disease Control and Prevention and NORC at the University of Chicago as part of a larger project to assess the public health emergency preparedness and response research priorities of state and local health departments. Results Overall, 30% of survey respondents indicated that health department staff were involved in public health preparedness and response research-related activities. Thirty-four percent indicated that they were extremely or moderately familiar with emergency preparedness research and literature. Approximately 67% of respondents reported interest in receiving additional information and/or training related to the preparedness research and literature. The most frequently reported partners for collaboration in preparedness research–related activities were schools of public health (34%). Conclusions Our findings suggest that there is health department interest in learning more about preparedness and response science and that additional efforts are needed to increase health department participation in public health emergency preparedness and response research-related activities.

Surveillance is critical for improving population health. Public health surveillance systems generate information that drives action, and the data must be of sufficient quality and with a resolution and timeliness that matches objectives. In the context of scientific advances in public health surveillance, changing health care and public health environments, and rapidly evolving technologies, the aim of this article is to review public health surveillance systems. We consider their current use to increase the efficiency and effectiveness of the public health system, the role of system stakeholders, the analysis and interpretation of surveillance data, approaches to system monitoring and evaluation, and opportunities for future advances in terms of increased scientific rigor, outcomes-focused research, and health informatics.

Background The utility of healthcare utilization data from US emergency departments (EDs) for rapid monitoring of changes in influenza-like illness (ILI) activity was highlighted during the recent influenza A (H1N1) pandemic. Monitoring has tended to rely on detection algorithms, such as the Early Aberration Reporting System (EARS), which are limited in their ability to detect subtle changes and identify disease trends. Objective To evaluate a complementary approach, change point analysis (CPA), for detecting changes in the incidence of ED visits due to ILI. Methodology and principal findings Data collected through the Distribute project ([isdsdistribute.org][1]), which aggregates data on ED visits for ILI from over 50 syndromic surveillance systems operated by state or local public health departments were used. The performance was compared of the cumulative sum (CUSUM) CPA method in combination with EARS and the performance of three CPA methods (CUSUM, structural change model and Bayesian) in detecting change points in daily time-series data from four contiguous US states participating in the Distribute network. Simulation data were generated to assess the impact of autocorrelation inherent in these time-series data on CPA performance. The CUSUM CPA method was robust in detecting change points with respect to autocorrelation in time-series data (coverage rates at 90% when −0.2≤ρ≤0.2 and 80% when −0.5≤ρ≤0.5). During the 2008–9 season, 21 change points were detected and ILI trends increased significantly after 12 of these change points and decreased nine times. In the 2009–10 flu season, we detected 11 change points and ILI trends increased significantly after two of these change points and decreased nine times. Using CPA combined with EARS to analyze automatically daily ED-based ILI data, a significant increase was detected of 3% in ILI on April 27, 2009, followed by multiple anomalies in the ensuing days, suggesting the onset of the H1N1 pandemic in the four contiguous states. Conclusions and significance As a complementary approach to EARS and other aberration detection methods, the CPA method can be used as a tool to detect subtle changes in time-series data more effectively and determine the moving direction (ie, up, down, or stable) in ILI trends between change points. The combined use of EARS and CPA might greatly improve the accuracy of outbreak detection in syndromic surveillance systems. [1]: http://isdsdistribute.org

Social, political, and economic disruptions caused by natural and human-caused public health emergencies have catalyzed public health efforts to expand the scope of biosurveillance and increase the timeliness, quality, and comprehensiveness of disease detection, alerting, response, and prediction. Unfortunately, efforts to acquire, render, and visualize the diversity of health intelligence information are hindered by its wide distribution across disparate fields, multiple levels of government, and the complex interagency environment. Achieving this new level of situation awareness within public health will require a fundamental cultural shift in methods of acquiring, analyzing, and disseminating information. The notion of information “fusion” may provide opportunities to expand data access, analysis, and information exchange to better inform public health action.

Objective Electronic laboratory reporting has been promoted as a public health priority. The Office of the U.S. National Coordinator for Health Information Technology has endorsed two coding systems: Logical Observation Identifiers Names and Codes (LOINC) for laboratory test orders and Systemized Nomenclature of Medicine-Clinical Terms (SNOMED CT) for test results. Materials and Methods We examined LOINC and SNOMED CT code use in electronic laboratory data reported in 2011 by 63 non-federal hospitals to BioSense electronic syndromic surveillance system. We analyzed the frequencies, characteristics, and code concepts of test orders and results. Results A total of 14,028,774 laboratory test orders or results were reported. No test orders used SNOMED CT codes. To describe test orders, 77% used a LOINC code, 17% had no value, and 6% had a non-informative value, “OTH”. Thirty-three percent (33%) of test results had missing or non-informative codes. For test results with at least one informative value, 91.8% had only LOINC codes, 0.7% had only SNOMED codes, and 7.4% had both. Of 108 SNOMED CT codes reported without LOINC codes, 45% could be matched to at least one LOINC code. Conclusion Missing or non-informative codes comprised almost a quarter of laboratory test orders and a third of test results reported to BioSense by non-federal hospitals. Use of LOINC codes for laboratory test results was more common than use of SNOMED CT. Complete and standardized coding could improve the usefulness of laboratory data for public health surveillance and response.

AFTER DECLINING EVERY YEAR since 1990, and less than 2 years after the launching of the National Plan to Eliminate Syphilis in the United States, rates of primary and secondary syphilis increased slightly in 2001.1 New epidemics involving men who have sex with men (MSM) have since been detected in most major US cities. If we could identify the persons who are most likely to acquire the next syphilis infections and why, we might be able to reach them early and prevent acquisition or reach them soon after they are infected and treat them before they transmit to others. This requires identifying characteristics of persons acquiring infection, how they are meeting partners, and how they are transmitting infection. When this information is known, we can warn the population at risk so they can take precautions to avoid infection or perhaps recognize an infection when they get it. We can also more effectively target screening campaigns and alert health care workers to look for infections among persons at risk. We also want to know how large the current syphilis epidemic will become because it will help with resource allocation decisions. Interventions early in an epidemic may halt transmission that could otherwise eventually become highly magnified. However, effective interventions can be expensive, even early in an epidemic. It is easier to justify extensive interventions for an epidemic that would otherwise grow to millions of cases (e.g., acquired immunodeficiency syndrome [AIDS]) than it is for an epidemic that would ultimately involve a small number of cases (e.g., hantavirus pulmonary syndrome). Finally, we want to know what this epidemic is telling us about other sexually transmitted infections, particularly human immunodeficiency virus (HIV). There has been concern that advances in antiretroviral therapy were leading to disinhibition of the sexual behaviors that were changed due to the AIDS epidemic.2,3 A relaxation of safe-sex practices could lead to resurgence of HIV and AIDS; however, increases in HIV transmission can be very difficult to identify because of the long and variable incubation period. Thus, other indicators have been used to try to identify effectiveness of HIV prevention programs.4 Some studies have suggested there have been increases in unprotected anal sex.3,5,6 Other studies suggest gonorrhea rates have increased among MSM.6,7 Is the current syphilis epidemic another indication that HIV transmission is increasing? We will address these questions by reviewing surveillance data reported to CDC and published epidemiologic research from the United States and elsewhere.

The US Federal Government has considerable interest in supporting research into preparedness. Because of the diverse nature of possible threats and the responsibilities of different agencies, a number of different programs have been developed. Perspectives from representatives from 3 of the leading agencies; the Department of Homeland Security, the Centers from Disease Control and Prevention, and the National Institutes of Health, are described herein.

Little information is available in the United States regarding the incidence and distribution of diseases caused by critical microbiologic agents with the potential for use in acts of terrorism. We describe disease-specific, demographic, geographic, and seasonal distribution of selected bioterrorism-related conditions (anthrax, botulism, brucellosis, cholera, plague, tularemia, and viral encephalitides) reported to the National Notifiable Diseases Surveillance System in 1992 to 1999. Tularemia and brucellosis were the most frequently reported diseases. Anthrax, plague, western equine encephalitis, and eastern equine encephalitis were rare. Higher incidence rates for cholera and plague were noted in the western United States and for tularemia in the central United States. Overall, the incidence of conditions caused by these critical agents in the United States is low. Individual case reports should be considered sentinel events. For potential bioterrorism-related conditions that are endemic and have low incidence, the use of nontraditional surveillance methods and complementary data sources may enhance our ability to rapidly detect changes in disease incidence.

Electronic Laboratory Reporting (ELR) has the potential to be more accurate, timely, and cost-effective. However, the continuing use of non-standard, local codes to represent laboratory test results complicates the use of ELR data in public health practice. Use of structured and standardized coding system(s) to support the concepts represented by local codes improves the computational characteristics of ELR data. We examined the use of LOINC and SNOMED CT codes for coding laboratory tests in hospital laboratory reports. We found that the hospitals more frequently used LOINC codes than SNOMED CT in reporting test results.

Objective. —To describe the health status of and to detect disease outbreaks in the population affected by Hurricane Andrew in south Dade County, Florida. Design. —The Florida Department of Health and Rehabilitative Services and the US Army conducted active surveillance for gastrointestinal illness, respiratory illness, injury, and other index conditions by monitoring civilian and service member visits to care sites (civilian and military free care sites and hospital emergency departments) from August 30 (1 week after the hurricane's landfall) through September 30, 1992. Setting. —South Dade County, Florida. Main Outcome Measures. —Proportional morbidity: the number of daily visits for each index condition divided by the total number of visits, expressed as a percentage. Morbidity rate: the total number of daily visits by service members divided by the total number of service members, expressed as a percentage. Results. —Six index conditions accounted for 41.3% of visits to civilian free care sites: diarrhea (4.7%), cough (4.7%), other infection (9.6%), rash (5.4%), animal bite (1.2%), and injury (15.7%). At military free care sites, five index conditions accounted for 75.7% of civilian visits: injury (23.7%), dermatologic illness (12.4%), respiratory illness (9.9%), gastrointestinal illness (5.3%), and other medical conditions (24.4%). Two index conditions accounted for 54.1% of service member visits: injury (36.2%) and dermatologic illness (17.9%). During the 5 weeks after the hurricane, proportional morbidity from injury decreased; proportional morbidity from respiratory illness increased; and proportional morbidity from diarrhea was stable. No infectious disease outbreaks occurred. Conclusions. —Injuries were an important source of morbidity throughout the surveillance period, especially among service members. Enteric and respiratory agents did not cause disease outbreaks, despite alarming rumors to the contrary. (JAMA. 1993;270:591-594)

Since human immunodeficiency virus (HIV) is predominantly sexually transmitted, serologic surveys for HIV infection in sexually transmitted disease (STD) clinics provide sentinel observations regarding HIV epidemiology. Over the past decade, 17,207 systematically collected sera from patients attending Baltimore STD clinics were analyzed. From 1979 through 1989, HIV seroprevalence rose from 0.23% to 5.35%, increasing significantly in both men and women (P less than .001). Due to a marked increase in HIV infection among women during the mid-1980s, the male-to-female ratio of HIV infection declined from 16:1 in 1979-1982 to 1.0 in 1988-1989. HIV seroprevalence increased significantly (P less than .001) in all age groups, with the greatest increase among teenagers, rising from 0.18% in 1979-1983 to 2.1% in 1987-1989 (P less than .001). Although HIV seroprevalence was higher among whites than blacks during the early 1980s, it increased in blacks subsequently (P less than .001), eventually resulting in a greater rate among black than white clinic patients (P less than .01). These data reflect the evolution of the HIV epidemic in US inner cities. HIV prevalence has increased greater than 20-fold, with recent increases being most marked among women, teenagers, and blacks. Additional resources will undoubtedly be required to support further intensive behavioral and educational programs targeted at adolescents and inner-city minorities.

African Americans carry the largest disease burden for bacterial sexually transmitted diseases (STDs) in the United States. These infections can have a devastating impact on sexual and reproductive health if they are not diagnosed and treated. Traditionally, public health efforts to prevent and control bacterial STDs have been through surveillance, clinical services, partner management, and behavioral intervention strategies. However, the persistence of disparities in STDs indicates that these strategies are not achieving sufficient impact in African American communities. It may be that factors such as limited access, acceptability, appropriateness, and affordability of services reduce the efficacy of these strategies for African American communities. In this article we describe the STD prevention strategies and highlight the challenges and implications of these strategies in addressing disparities in African American communities.

Objectives This study investigates the data suppression or statistical disclosure limitation (DL) practices used during surveillance data Release by sexually transmitted disease (STD) prevention programs. Methods We classified DL strategies from a Web-based data query system that collected data from state health departments. We tested mean STD incidence Rates in states that used data suppression versus those that did not. Results Five types of DL were identified: no suppression (n = 15), numerator-only (n = 10), denominator-only (n = 6), demographic-only (n = 7), and mixed strategies (n = 12). Twenty-two states (62%) used data suppression strategies differently through time. Chlamydia, gonorrhea, and syphilis Rates were higher in the nonsuppression states than those of the suppression states (P = .03, P = .008, P = .009, Respectively). Conclusions Cell suppression is the preferred method of DL used by STD prevention programs. More Research is needed to evaluate the effectiveness of this strategy as a means of balancing the public health utility of the data tables and the protection of confidentiality.

• A serologic survey of 4863 patients attending two inner-city sexually transmitted disease clinics was conducted in 1988 1 year after an initial survey to reassess the prevalence and associated risk factors for human immunodeficiency virus (HIV) infection. The HIV seroprevalence rates had not changed significantly (5.2% in 1987, 4.9% in 1988), and remained higher among men (5.6%) than among women (3.6%). The HIV seroprevalence increased steadily with age, to 34 years in women and to 39 years in men. Of patients with a reactive syphilis serologic test result, 24.3% were HIV infected compared with 3.5% of patients with a nonreactive test for syphilis. In multivariate analysis, a reactive serologic test for syphilis was significantly associated with HIV infection in all major risk behavior categories. Among heterosexuals who denied parenteral drug abuse, HIV infection rates were 6.8 and 8.7 times greater for women and men, respectively, who had a reactive serologic test for syphilis. Evidence of heterosexual transmission of HIV was further suggested by a change in HIV seroprevalence in women from 3.0% in 1987 to 3.6% in 1988, a male to female HIV infection ratio of 1.6, and a 3.0% prevalence of infection among patients who denied established risk factors. This was most evident among those younger than 25 years, in whom 72% of infected women and 46.2% of infected men denied high-risk behaviors. These data demonstrate the strong association between syphilis and HIV infection and the importance of heterosexual HIV transmission in patients attending sexually transmitted disease clinics. This study underscores the need for a more comprehensive control program for sexually transmitted diseases, including syphilis and HIV infection. (Arch Intern Med.1990;150:1297-1302)

Background Timeliness is a key performance measure of public health surveillance systems. Timeliness can vary by disease, intended use of the data, and public health system level. Studies were reviewed to describe methods used to evaluate timeliness and the reporting timeliness of National Notifiable Diseases Surveillance System (NNDSS) data was evaluated to determine if this system could support timely notification and state response to multistate outbreaks. Methods Published papers that quantitatively measured timeliness of infectious disease surveillance systems operating in the U.S. were reviewed. Median reporting timeliness lags were computed for selected nationally notifiable infectious diseases based on a state-assigned week number and various date types. The percentage of cases reported within the estimated incubation periods for each disease was also computed. Results Few studies have published quantitative measures of reporting timeliness; these studies do not evaluate timeliness in a standard manner. When timeliness of NNDSS data was evaluated, the median national reporting delay, based on date of disease onset, ranged from 12 days for meningococcal disease to 40 days for pertussis. Diseases with the longer incubation periods tended to have a higher percentage of cases reported within its incubation period. For acute hepatitis A virus infection, which had the longest incubation period of the diseases studied, more than 60% of cases were reported within one incubation period for each date type reported. For cryptosporidiosis, Escherichia coli O157:H7 infection, meningococcal disease, salmonellosis, and shigellosis, less than 40% of cases were reported within one incubation period for each reported date type. Conclusion Published evaluations of infectious disease surveillance reporting timeliness are few in number and are not comparable. A more standardized approach for evaluating and describing surveillance system timeliness should be considered; a recommended methodology is presented. Our analysis of NNDSS reporting timeliness indicated that among the conditions evaluated (except for acute hepatitis A infection), the long reporting lag and the variability across states limits the usefulness of NNDSS data and aberration detection analysis of those data for identification of and timely response to multistate outbreaks. Further evaluation of the factors that contribute to NNDSS reporting timeliness is warranted.

Public health reporting of laboratory results requires unambiguous identification of the test performed and the result observed. Some laboratories are currently using Logical Observation Identifier Names and Codes (LOINC) for the electronic reporting of laboratory tests and their results to public health departments. Initial use revealed inconsistent identification and use of LOINC concepts by laboratories and public health agencies and an inability to systematically extend, for public health use, the tables when adding new concepts. We applied simple, logical rules to existing LOINC concepts to facilitate the creation of a hierarchy of concepts and to allow the identification and specification of appropriate terms for public health reporting and subsequent data aggregation. The hierarchy also allows the systematic addition of new concepts further supporting public health reporting. Application of the hierarchy is illustrated by using all laboratory LOINC concepts assigned to the subset of microbiology test types (CLASS MICRO).

Despite state and local laws requiring medical providers to report notifiable infectious diseases to public health authorities, reporting is believed to be incomplete. Through means of an analytical literature review, the authors synthesize current knowledge on the completeness of disease reporting and identify factors associated with reporting completeness. The review was limited to published studies, conducted in the United States between 1970 and 1999, that quantitatively assessed infectious disease reporting completeness. Thirty-three studies met the inclusion criteria. Reporting completeness, expressed between 0% and 100%, was treated as the dependent outcome variable in statistical analysis; disease, study location, time period, study design, and study size were treated as independent variables. Fifty-six distinct measures of reporting completeness were identified for 21 diseases. Reporting completeness varied from 9% to 99% and was most strongly associated with the disease being reported. The mean reporting completeness for acquired immunodeficiency syndrome, sexually transmitted diseases, and tuberculosis as a group was significantly higher (79%) than for all other diseases combined (49%) (p < 0.01).

Objectives. This analysis describes trends in the prevalence of genital chlamydial infection in economically disadvantaged young women entering a national job training program. Methods. We examined chlamydia test data for May 1990 through June 1997 for women aged 16 to 24 years who enrolled in the program. The significance of trends was evaluated with the χ2 test for trend. Results. Prevalence of chlamydial infection declined 32.9%, from 14.9% in 1990 to 10.0% in 1997 (P < .001). Prevalence decreased significantly in all age groups, racial/ethnic groups, and geographic regions. Conclusions. The decrease in prevalence of chlamydial infection suggests that prevention activities have reached disadvantaged women across the United States; however, prevalence of chlamydial infection remains high, and enhanced prevention efforts in disadvantaged communities are urgently needed.

BACKGROUND AND OBJECTIVE: Because genital Chlamydia trachomatis infections and their sequelae have a major impact on individuals and the health care system, it is important to periodically update estimates of chlamydia incidence and prevalence in the United States. STUDY DESIGN: Chlamydia incidence and prevalence were estimated using: (1) a method based on estimates of population-specific chlamydia prevalence, and (2) a method based on the chlamydia-to-gonorrhea case rate ratio. RESULTS: Using the prevalence-based method, point prevalence among persons 15 to 44 years of age was estimated to be 1.6 million chlamydial infections, and annual incidence, 2.4 million cases per year. Using a method based on the ratio of reported gonorrhea to chlamydia, incidence was estimated to be 2.8 million infections per year, and prevalence, 1.9 million. Adjustment for sensitivity of diagnostic tests yielded annual incidence estimates of 2.5 to 3.3 million infections. CONCLUSIONS: Using two methods, we estimated the annual incidence of chlamydial infections in the United States among persons 15 to 44 years of age to be approximately 3 million infections. Critical data needed for more precise estimates include: sensitivity of current diagnostics, better data on infections in males, the current extent of underdetection and underreporting, and better data on duration of infection in men and women.

BACKGROUND AND OBJECTIVES To determine the proportion of HIV-infected sexually transmitted disease (STD) clinic patients identified during routine, voluntary HIV counseling and testing and to characterize patients accepting and refusing counseling and testing, we linked data from a blinded HIV seroprevalence survey to data from the HIV counseling and testing program. GOAL OF THIS STUDY This study characterizes patients accepting and refusing routine HIV counseling and testing in two public STD clinics. STUDY DESIGN A cross-sectional, blinded HIV seroprevalence survey was conducted of 1,232 STD clinic patients offered HIV counseling and testing. RESULTS HIV seroprevalence was higher among patients who refused voluntary testing (7.8% versus 3.6%, P = 0.001). Patients who refused testing were more likely to report a prior HIV test (45.6% versus 27.2%; P < 0.001). Among patients reporting a prior HIV test, differences were noted between reported prior results, both positive and negative, and blinded results. CONCLUSIONS HIV-infected STD patients may not be detected by routine HIV testing, and self-reported HIV results should be confirmed.

To determine whether the simultaneous, partial repeal of needle prescription and drug paraphernalia laws in Connecticut affected purchasing and usage of needles and syringes (syringes) by injecting-drug users (IDUs) and risk of needlestick injuries to police officers, we conducted two serial cross-sectional surveys with IDUs recruited in drug treatment centers, correctional facilities, and health department settings. Reports of needlestick injuries among Hartford police officers were reviewed before and after the new laws. Among IDUs who reported ever sharing a syringe, syringe-sharing decreased after the new laws (52% before vs. 31% after; p = 0.02). Fewer IDUs reported purchasing syringes on the street after the new laws (74% before vs. 28% after; p < 0.0001). More IDUs reported purchasing syringes from a pharmacy after the new laws (19% before vs. 78% after; p < 0.0001). Eight to eleven months after the new laws were enacted, over two thirds (91 of 134) of active IDUs interviewed were aware of both new laws. Needlestick injury rates among Hartford police officers were lower after the new laws (six injuries in 1,007 drug-related arrests for 6-month period before new laws vs. two in 1,032 arrests for 6-month period after new laws). The changes in Connecticut laws were associated with decreases in self-reported syringe-sharing and increases in purchasing by IDUs of sterile syringes from reliable sources, suggesting that the simultaneous repeal of both prescription and paraphernalia laws is an important HIV prevention strategy.

Background Notifiable disease surveillance in the United States is predominantly a passive process that is often limited by poor timeliness and low sensitivity. Interoperable tools are needed that interact more seamlessly with existing clinical and laboratory data to improve notifiable disease surveillance. Description The Public Health Surveillance Knowledgebase (PHSkb™) is a computer database designed to provide quick, easy access to domain knowledge regarding notifiable diseases and conditions in the United States. The database was developed using Protégé ontology and knowledgebase editing software. Data regarding the notifiable disease domain were collected via a comprehensive review of state health department websites and integrated with other information used to support the National Notifiable Diseases Surveillance System (NNDSS). Domain concepts were harmonized, wherever possible, to existing vocabulary standards. The knowledgebase can be used: 1) as the basis for a controlled vocabulary of reportable conditions needed for data aggregation in public health surveillance systems; 2) to provide queriable domain knowledge for public health surveillance partners; 3) to facilitate more automated case detection and surveillance decision support as a reusable component in an architecture for intelligent clinical, laboratory, and public health surveillance information systems. Conclusions The PHSkb provides an extensible, interoperable system architecture component to support notifiable disease surveillance. Further development and testing of this resource is needed.