Thermography involves the quantification of emitted radiation to measure temperature, and provides a quick non-invasive means to measure body temperature. Infrared thermography (IRT) can be implemented at international airports in order to detect febrile passengers and prevent the introduction and spread of infectious diseases to other countries. Border control strategies were enacted as a response to the emergence of Severe Acute Respiratory Syndrome (SARS) in 2003, which included the introduction of non-contact infrared thermal scanners at international airports and bus or railway stations for mass screening of individuals. IRT has also been used as a measure to detect and prevent influenza outbreaks and transmission of dengue fever across borders.
IRT may be influenced by several confounding factors including age and outdoor temperature. In addition, results from studies looking at IRT as a tool to detect fever tend to have small positive predictive values due to the small prevalence of febrile passengers. However, advantages of using IRT include its ability to screen mass numbers of individuals and reduce close contacts with infected individuals. Recently, the 2014 Ebola epidemic in West Africa has renewed concerns of disease transmission across borders and increased vigilance to identify individuals entering the country who may harbour infection.
The purpose of this review is to examine the effectiveness of screening for fever at border crossings to reduce the risk of infectious disease outbreaks.
Disclaimer: The Rapid Response Service is an information service for those involved in planning and providing health care in Canada. Rapid responses are based on a limited literature search and are not comprehensive, systematic reviews. The intent is to provide a list of sources of the best evidence on the topic that CADTH could identify using all reasonable efforts within the time allowed. Rapid responses should be considered along with other types of information and health care considerations. The information included in this response is not intended to replace professional medical advice, nor should it be construed as a recommendation for or against the use of a particular health technology. Readers are also cautioned that a lack of good quality evidence does not necessarily mean a lack of effectiveness particularly in the case of new and emerging health technologies, for which little information can be found, but which may in future prove to be effective. While CADTH has taken care in the preparation of the report to ensure that its contents are accurate, complete and up to date, CADTH does not make any guarantee to that effect. CADTH is not liable for any loss or damages resulting from use of the information in the report.
