Leveraging syndromic surveillance

Evaluation of the ability of standardized supports to improve public health response to syndromic surveillance for respiratory diseases in Canada

Background

Despite widespread implementation of syndromic surveillance systems within public health agencies, previous studies of the implementation and use of these systems have indicated that the functions and responses taken in response to syndromic surveillance data vary widely according to local context and preferences. The objective of the Syndromic Surveillance Evaluation Study was to develop and implement standardized supports in local public health agencies in Ontario, Canada, and evaluate the ability of these supports to affect actions taken as part of public health communicable disease control programs.

Methods

Local public health agencies (LPHA) in Ontario, which used syndromic surveillance based on emergency department visits for respiratory disease, were recruited and randomly allocated to the study intervention or control group. The intervention group health agencies received standardized supports in terms of a standardized aberrant event detection algorithm and a response protocol dictating steps to investigate and assess the public health significance of syndromic surveillance alerts. The control group continued with their pre-existing syndromic surveillance infrastructure and processes. Outcomes were assessed using logbooks, which collected quantitative and qualitative information about alerts received, investigation steps taken, and public health responses. The study was conducted prospectively for 15 months (October 2013 to February 2015).

Results

Fifteen LPHAs participated in the study (n = 9 intervention group, n = 6 control group). A total of 1,969 syndromic surveillance alerts were received by all LPHAs. Variations in the types and amount of responses varied by LPHA, in particularly differences were noted by the size of the health unit. Smaller health units had more challenges to both detect and mount a response to any alerts. LPHAs in the control group were more likely to declare alerts to have public health significance and to initiate any action. Regression models using repeated measures showed an interaction between the year (Year 1 versus Year 2) and the intervention as well as an interaction between year and sustained nature of the alert. Both of these were linked to the control health units reporting more “watchful waiting”.

Conclusions

This study raises questions about the effectiveness of using standardized protocols to improve the performance of syndromic surveillance in a decentralized public health system. Despite efforts to create standardized protocols and engage public health agencies in the process, no significant differences in the effective use of syndromic alerts were observed beyond year 1. It also raises questions about the minimum capacity of the agency and minimum population size that are required for an effective response.

New digital technologies for the surveillance of infectious diseases at mass gathering events

Outbreaks of infectious diseases at mass gatherings can strain the health system of the host region and pose a threat to local and global health. In addition to strengthening existing surveillance systems, most host nations also use novel technologies to assess disease risk and augment traditional surveillance approaches. We review novel approaches to disease surveillance using the Internet, mobile phone applications, and wireless sensor networks. These novel approaches to disease surveillance can result in prompt detection.

Public Health in the Field and the Emergency Operations Center: Methods for Implementing Real-Time Onsite Syndromic Surveillance at Large Public Events

Objective

To develop an onsite syndromic surveillance system for the early detection of public health emergencies and outbreaks at large public events.

Methods

As the third largest public health jurisdiction in the United States, Maricopa County Department of Public Health has worked with academic and first-response partners to create an event-targeted syndromic surveillance (EVENTSS) system. This system complements long-standing traditional emergency department-based surveillance and provides public health agencies with rapid reporting of possible clusters of illness.

Results

At 6 high profile events, 164 patient reports were collected. Gastrointestinal and neurological syndromes were most commonly reported, followed by multisyndromic reports. Neurological symptoms were significantly increased during hot weather events. The interview rate was 2 to 7 interviews per 50 000 people per hour, depending on the ambient temperature.

Discussion

Study data allowed an estimation of baseline values of illness occurring at large public events. As more data are collected, prediction models can be built to determine threshold levels for public health response.

Conclusions

EVENTSS was conducted largely by volunteer public health graduate students, increasing the response capacity for the health department. Onsite epidemiology staff could make informed decisions and take actions quickly in the event of a public health emergency. (Disaster Med Public Health Preparedness. 2013;0:1–8)

Sustaining surveillance: evaluating syndromic surveillance in the Pacific

Prior to the 2009 H1N1 pandemic, the Pacific Island Countries and Territories (PICTs) had agreed to develop a standardised, simple syndromic surveillance system to ensure compliance with International Health Regulations requirements (rapid outbreak detection, information sharing and response to outbreaks). In October 2010, the new system was introduced and over the next 12 months implemented in 20 of 22 PICTs. An evaluation was conducted to identify strengths and weaknesses of the system, ease of use and possible points for improvement. An in-country quantitative and qualitative evaluation in five PICTs identified that the most important determinants of the system's success were: simplicity of the system; support from all levels of government; clearly defined roles and responsibilities; feedback to those who collect the data; harmonisation of case definitions; integration of data collection tools into existing health information systems; and availability of clinical and epidemiological advice from external agencies such as the World Health Organization and the Secretariat of the Pacific Community. Regional reporting of alerts, outbreaks and outbreak updates has dramatically increased since implementation of the system. This syndromic system will assist PICTs to detect future influenza pandemics and other emerging infectious diseases and to rapidly contain outbreaks in the Pacific.

A survey of usage protocols of syndromic surveillance systems by state public health departments in the United States

OBJECTIVE

To broadly describe current syndromic surveillance systems in use throughout the United States and to provide basic descriptive information on responses to syndromic system signals.

METHODS

Cross-sectional survey (telephone and e-mail) of state epidemiologists in all 50 states and the District of Columbia.

RESULTS

Forty-one states participated in the survey for a response rate of 80 percent. Thirty-three states (80%) had at least one syndromic surveillance system in addition to BioSense operating within the state. Every state with an urban area at highest risk of a terrorist attack reported monitoring syndromic surveillance data, and a state's overall preparedness level was not related to the presence (or lack) of operational syndromic surveillance systems. The most common syndromic surveillance systems included BioSense (n = 20, 61%) and RODS (n = 13, 39%). Seventy-six percent of states with syndromic surveillance initiated investigations at the state level, 64 percent at the county level, and 45 percent at both the state and county levels.

CONCLUSIONS

The majority of states reported using syndromic surveillance systems, with greatest penetration in those at highest risk for a terrorist attack. Most states used multiple systems and had varied methods (central and local) of responding to alerts, indicating the need for detailed response protocols.