Developing open source, self-contained disease surveillance software applications for use in resource-limited settings.

BACKGROUND: Emerging public health threats often originate in resource-limited countries. In recognition of this fact, the World Health Organization issued revised International Health Regulations in 2005, which call for significantly increased reporting and response capabilities for all signatory nations. Electronic biosurveillance systems can improve the timeliness of public health data collection, aid in the early detection of and response to disease outbreaks, and enhance situational awareness. METHODS: As components of its Suite for Automated Global bioSurveillance (SAGES) program, The Johns Hopkins University Applied Physics Laboratory developed two open-source, electronic biosurveillance systems for use in resource-limited settings. OpenESSENCE provides web-based data entry, analysis, and reporting. ESSENCE Desktop Edition provides similar capabilities for settings without internet access. Both systems may be configured to collect data using locally available cell phone technologies. RESULTS: ESSENCE Desktop Edition has been deployed for two years in the Republic of the Philippines. Local health clinics have rapidly adopted the new technology to provide daily reporting, thus eliminating the two-to-three week data lag of the previous paper-based system. CONCLUSIONS: OpenESSENCE and ESSENCE Desktop Edition are two open-source software products with the capability of significantly improving disease surveillance in a wide range of resource-limited settings. These products, and other emerging surveillance technologies, can assist resource-limited countries compliance with the revised International Health Regulations.

SAGES: a suite of freely-available software tools for electronic disease surveillance in resource-limited settings.

Public health surveillance is undergoing a revolution driven by advances in the field of information technology. Many countries have experienced vast improvements in the collection, ingestion, analysis, visualization, and dissemination of public health data. Resource-limited countries have lagged behind due to challenges in information technology infrastructure, public health resources, and the costs of proprietary software. The Suite for Automated Global Electronic bioSurveillance (SAGES) is a collection of modular, flexible, freely-available software tools for electronic disease surveillance in resource-limited settings. One or more SAGES tools may be used in concert with existing surveillance applications or the SAGES tools may be used en masse for an end-to-end biosurveillance capability. This flexibility allows for the development of an inexpensive, customized, and sustainable disease surveillance system. The ability to rapidly assess anomalous disease activity may lead to more efficient use of limited resources and better compliance with World Health Organization International Health Regulations.

Bayesian information fusion networks for biosurveillance applications.

This study introduces new information fusion algorithms to enhance disease surveillance systems with Bayesian decision support capabilities. A detection system was built and tested using chief complaints from emergency department visits, International Classification of Diseases Revision 9 (ICD-9) codes from records of outpatient visits to civilian and military facilities, and influenza surveillance data from health departments in the National Capital Region (NCR). Data anomalies were identified and distribution of time offsets between events in the multiple data streams were established. The Bayesian Network was built to fuse data from multiple sources and identify influenza-like epidemiologically relevant events. Results showed increased specificity compared with the alerts generated by temporal anomaly detection algorithms currently deployed by NCR health departments. Further research should be done to investigate correlations between data sources for efficient fusion of the collected data.

The pandemic influenza policy model: a planning tool for military public health officials.

The Pandemic Influenza Policy Model (PIPM) is a collaborative computer modeling effort between the U.S. Department of Defense (DoD) and the Johns Hopkins University Applied Physics Laboratory. Many helpful computer simulations exist for examining the propagation of pandemic influenza in civilian populations. We believe the mission-oriented nature and structured social composition of military installations may result in pandemic influenza intervention strategies that differ from those recommended for civilian populations. Intervention strategies may differ between military bases because of differences in mission, location, or composition of the population at risk. The PIPM is a web-accessible, user-configurable, installation-specific disease model allowing military planners to evaluate various intervention strategies. Innovations in the PIPM include expanding on the mathematics of prior stochastic models, using military-specific social network epidemiology, utilization of DoD personnel databases to more accurately characterize the population at risk, and the incorporation of possible interventions, e.g., pneumococcal vaccine, not examined in previous models.

Enhancing Disease Surveillance Event Communication Among Jurisdictions.

Automated disease surveillance systems are becoming widely used by the public health community. However, communication among non-collocated and widely dispersed users still needs improvement. A web-based software tool for enhancing user communications was completely integrated into an existing automated disease surveillance system and was tested during two simulated exercises and operational use involving multiple jurisdictions. Evaluation of this tool was conducted by user meetings, anonymous surveys, and web logs. Public health officials found this tool to be useful, and the tool has been modified further to incorporate features suggested by user responses. Features of the automated disease surveillance system, such as alerts and time series plots, can be specifically referenced by user comments. The user may also indicate the alert response being considered by adding a color indicator to their comment. The web-based event communication tool described in this article provides a common ground for collaboration and communication among public health officials at different locations.

Extended-dose nevirapine to 6 weeks of age for infants to prevent HIV transmission via breastfeeding in Ethiopia, India, and Uganda: an analysis of three randomised controlled trials.

BACKGROUND: UNICEF/WHO recommends that infants born to HIV-infected mothers who do not have access to acceptable, feasible, affordable, sustainable, and safe replacement feeding should be exclusively breastfed for at least 6 months. The aim of three trials in Ethiopia, India, and Uganda was to assess whether daily nevirapine given to breastfed infants through 6 weeks of age can decrease HIV transmission via breastfeeding. METHODS: HIV-infected women breastfeeding their infants were eligible for participation. Participants were randomly assigned to receive either single-dose nevirapine (nevirapine 200 mg to women in labour and nevirapine 2 mg/kg to newborns after birth) or 6 week extended-dose nevirapine (nevirapine 200 mg to women in labour and nevirapine 2 mg/kg to newborn babies after birth plus nevirapine 5 mg daily from days 8-42 for the infant). The randomisation sequences were generated by computer at a central data coordinating centre. The primary endpoint was HIV infection at 6 months of age in infants who were HIV PCR negative at birth. Analyses were by modified intention to treat, excluding infants with missing specimens and those with indeterminate or confirmed HIV infection at birth. These studies are registered with ClinicalTrials.gov, numbers NCT00074399, NCT00061321, and NCT00639938. FINDINGS: 2024 liveborn infants randomised in the study had at least one specimen tested before 6 months of age (1047 infants in the single-dose group and 977 infants in the extended-dose group). The modified intention-to-treat population included 986 infants in the single-dose group and 901 in the extended-dose group. At 6 months, 87 children in the single-dose group and 62 in the extended-dose group were infected with HIV (relative risk 0.80, 95% CI 0.58-1.10; p=0.16). At 6 weeks of age, 54 children in the single-dose group and 25 in the extended-dose group were HIV positive (0.54, 0.34-0.85; p=0.009). 393 infants in the single-dose group and 346 in the extended-dose group experienced grade 3 or 4 serious adverse events during the study (p=0.54). INTERPRETATION: Although a 6-week regimen of daily nevirapine might be associated with a reduction in the risk of HIV transmission at 6 weeks of age, the lack of a significant reduction in the primary endpoint-risk of HIV transmission at 6 months-suggests that a longer course of daily infant nevirapine to prevent HIV transmission via breast milk might be more effective where access to affordable and safe replacement feeding is not yet available and where the risks of replacement feeding are high. FUNDING: US National Institutes of Health; US National Institute of Allergy and Infectious Diseases; Fogarty International Center.

Event communication in a regional disease surveillance system.

When real-time disease surveillance is practiced in neighboring states within a region, public health users may benefit from easily sharing their concerns and findings regarding potential health threats. To better understand the need for this capability, an event communications component (ECC) was added to the National Capital Region Disease Surveillance System, an operational biosurveillance system employed in the District of Columbia and in surrounding Maryland and Virginia counties. Through usage analysis and user survey methods, we assessed the value of the enhanced system in daily operational use and during two simulated exercises. Results suggest that the system has utility for regular users of the system as well as suggesting several refinements for future implementations.

Weekly rifapentine/isoniazid or daily rifampin/pyrazinamide for latent tuberculosis in household contacts.

RATIONALE: Treatment of latent tuberculosis (TB) infection with weekly rifapentine and isoniazid is a potentially effective alternative to current therapies. OBJECTIVES: To compare the efficacy of weekly rifapentine/isoniazid to daily rifampin/pyrazinamide in preventing TB in household contacts of patients with pulmonary TB in Brazil. METHODS: Contacts of patients with TB were randomized to rifapentine 900 mg/isoniazid 900 mg once weekly for 12 wk or rifampin 450-600 mg/pyrazinamide 750-1,500 mg daily for 8 wk and followed for at least 2 yr. MEASUREMENTS: TB rates, adverse events, and adherence to therapy. MAIN RESULTS: A total of 399 household contacts were enrolled, 206 in the rifapentine/isoniazid arm and 193 in the rifampin/pyrazinamide arm. The median age was 34 yr, median weight was 63 kg, 60% of participants were female, and only one patient was HIV infected. Rifapentine/isoniazid was well tolerated, but the trial was halted by the investigators before completion because of unanticipated hepatotoxicity in the rifampin/pyrazinamide arm. Twenty of 193 participants (10%) receiving rifampin/pyrazinamide experienced grade 3 or 4 hepatotoxicity, compared with 2 of 206 participants (1%) on rifapentine/isoniazid (p<0.001). There were no hospitalizations or deaths due to hepatotoxicity, and all participants' liver enzyme levels returned to normal during follow-up. During follow-up, four cases of active TB developed, three in the rifapentine/isoniazid group and one in the rifampin/pyrazinamide group (1.46 vs. 0.52%; difference, 0.94%; 95% confidence interval, -1.6 to 3.7%). CONCLUSIONS: Rifapentine/isoniazid was better tolerated than rifampin/pyrazinamide and was associated with good protection against TB. Rifapentine/isoniazid weekly for 12 wk is likely a promising therapy for latent TB infection.

Evaluation of a whole-blood interferon-gamma release assay for the detection of Mycobacterium tuberculosis infection in 2 study populations.

A whole-blood interferon-gamma release assay (IGRA) is being evaluated for its potential to replace the tuberculin skin test (TST) for detecting Mycobacterium tuberculosis infection. To test the assay in a population in which tuberculosis is highly endemic and in another population that is representative of an urban United States population, 253 volunteers from Ethiopia and 175 volunteers from Baltimore were studied for responsiveness on IGRA compared with a simultaneously performed TST. The agreement between the 2 tests, beyond that due to chance, was 68% among subjects from Baltimore and only 35% among those from Ethiopia. IGRA had a sensitivity of 71%, compared with 95% sensitivity for the TST, among 21 subjects who had undergone treatment for culture-confirmed tuberculosis. The specificity was 85% for IGRA and 96% for TST among 52 subjects with no known history of exposure to tuberculosis. In its current form, with purified protein derivative used as the stimulation antigen, the IGRA was found to perform poorly in comparison to the TST in diagnosing M. tuberculosis infection.

Servicio de orientacion y deteccion de VIH vinculado a un programa comunitario antituberculoso en una poblacion de alto riesgo / Wide-spread HIV counseling and testing linked to a community based tuberculosis control program in a high-risk population

La finalidad del trabajo que aqui se describe fue evaluarel tamizaje comunitario para la deteccion de los casos de infeccion por VIH vinculado a un programa de lucha anticuberculosa en una poblacion de alto riesgo de ambas infecciones. De mayo de 1990 a agosto de 1992, trabajadores de salud comunitarios se comunicaron con adultos en domicilios y dispensarios de Cite Soleil, Haiti, para ofrecerles servicios institucionales de asesoramiento individual y de deteccion de VIH y de tuberculosis. A todas las personas que aceptaron la prueba se les dio asesoramiento posterior sobre VIH. Las que tenian tuberculosis activa recibieron tratamiento y a las que tenian enfermedad latente mas infeccion por VIH se les dio la oportunidad de participar en un ensayo clinico sobre quimioprofilaxis antituberculosa. La elevada prevalencia de infeccion por VIH en la poblacion examinada, al compararsela con otros grupos sometidos a tamizaje en la misma comunidad, indica que las personas en alto riesgo de infeccion por VIH buscaron selectivamente o aceptaron someterse a las pruebas de tamizaje ofrecidas en los dispensarios de tuberculosis. Asimismo, a muchas personas se les diagnostico tuberculosis activa en una fase mas temprana de la enfermedad de lo que hubiera sido posible sin un programa de tamizaje. En general, los resultados indican que cuando el tamizaje comunitario para la deteccion de VIH es parte de un programa de lucha antituberculosa, el resultado puede ser una mejor focalizacion de destinatarios para las pruebas de deteccion de ambas infecciones

Widespread HIV counseling and testing linked to a community-based tuberculosis control program in a high-risk population

The aim of the work reported here was to evaluate community-wide screening for HIV infection that was linked to a tuberculosis control program in a population at high risk for both infections. Between May 1990 and August 1992, adults in Cité Soleil, Haiti, were recruited by community health workers at their homes and in clinics for individual, clinic-based counseling and testing for HIV and tuberculosis. All of the screened subjects were offered post-test HIV counseling. Those with active tuberculosis received treatment, while those with latent tuberculosis and HIV infection were offered an opportunity to participate in a trial of antituberculosis chemoprophylaxis. The 10 611 individuals screened for HIV represented 10.0 percent of the adult population in Cité Soleil. HIV infection was detected in 1 629 (15.4 percent) and active tuberculosis in 242 (2.3 percent). Latent M. tuberculosis infection was found in 4 800 (67.5 percent) of 7 309 community residents who completed tuberculosis screening, 781 (16.3 percent) of whom were coinfected with HIV. The high prevalence of HIV infection found in this screened population, as compared to other groups undergoing HIV screening in the same community, suggests that people at high risk for HIV infection selectively sought or accepted tuberculosis clinic screening. Also, many people with active tuberculosis were identified earlier in the course of their disease than they would have been in the absence of a screening program. Overall, the results indicate that community-based screening for HIV infection within a tuberculosis control program can result in effective targeting of screening for both infections

Widespread HIV counseling and testing linked to a community-based tuberculosis control program in a high-risk population

The aim of the work reported here was to evaluate community-wide screening for HIV infection that was linked to a tuberculosis control program in a population at high risk for both infections. Between May 1990 and August 1992, adults in Cité Soleil, Haiti, were recruited by community health workers at their homes and in clinics for individual, clinic-based counseling and testing for HIV and tuberculosis. All of the screened subjects were offered post-test HIV counseling. Those with active tuberculosis received treatment, while those with latent tuberculosis and HIV infection were offered an opportunity to participate in a trial of antituberculosis chemoprophylaxis. The 10 611 individuals screened for HIV represented 10.0 percent of the adult population in Cité Soleil. HIV infection was detected in 1 629 (15.4 percent) and active tuberculosis in 242 (2.3 percent). Latent M. tuberculosis infection was found in 4 800 (67.5 percent) of 7 309 community residents who completed tuberculosis screening, 781 (16.3 percent) of whom were coinfected with HIV. The high prevalence of HIV infection found in this screened population, as compared to other groups undergoing HIV screening in the same community, suggests that people at high risk for HIV infection selectively sought or accepted tuberculosis clinic screening. Also, many people with active tuberculosis were identified earlier in the course of their disease than they would have been in the absence of a screening program. Overall, the results indicate that community-based screening for HIV infection within a tuberculosis control program can result in effective targeting of screening for both infections

This article will also be published in Spanish in the Bol. OSP. Vol. 120(5), 1996

Servicio de orientacion y deteccion de VIH vinculado a un programa comunitario antituberculoso en una poblacion de alto riesgo / Wide-spread HIV counseling and testing linked to a community based tuberculosis control program in a high-risk population

La finalidad del trabajo que aqui se describe fue evaluarel tamizaje comunitario para la deteccion de los casos de infeccion por VIH vinculado a un programa de lucha anticuberculosa en una poblacion de alto riesgo de ambas infecciones. De mayo de 1990 a agosto de 1992, trabajadores de salud comunitarios se comunicaron con adultos en domicilios y dispensarios de Cite Soleil, Haiti, para ofrecerles servicios institucionales de asesoramiento individual y de deteccion de VIH y de tuberculosis. A todas las personas que aceptaron la prueba se les dio asesoramiento posterior sobre VIH. Las que tenian tuberculosis activa recibieron tratamiento y a las que tenian enfermedad latente mas infeccion por VIH se les dio la oportunidad de participar en un ensayo clinico sobre quimioprofilaxis antituberculosa. La elevada prevalencia de infeccion por VIH en la poblacion examinada, al compararsela con otros grupos sometidos a tamizaje en la misma comunidad, indica que las personas en alto riesgo de infeccion por VIH buscaron selectivamente o aceptaron someterse a las pruebas de tamizaje ofrecidas en los dispensarios de tuberculosis. Asimismo, a muchas personas se les diagnostico tuberculosis activa en una fase mas temprana de la enfermedad de lo que hubiera sido posible sin un programa de tamizaje. En general, los resultados indican que cuando el tamizaje comunitario para la deteccion de VIH es parte de un programa de lucha antituberculosa, el resultado puede ser una mejor focalizacion de destinatarios para las pruebas de deteccion de ambas infecciones

Este articulo se publico en ingles en el Bull. PAHO. Vol. 30(1), 1996