A profile of the online dissemination of national influenza surveillance data

Abstract

Background: Influenza surveillance systems provide important and timely information to health service providers on trends in the circulation of influenza virus and other upper respiratory tract infections. Online dissemination of surveillance data is useful for risk communication to health care professionals, the media and the general public. We reviewed national influenza surveillance websites from around the world to describe the main features of surveillance data dissemination.

Methods: We searched for national influenza surveillance websites for every country and reviewed the resulting sites where available during the period from November 2008 through February 2009. Literature about influenza surveillance was searched at MEDLINE for relevant hyperlinks to related websites. Non-English websites were translated into English using human translators or Google language tools.

Results: A total of 70 national influenza surveillance websites were identified. The percentage of developing countries with surveillance websites was lower than that of developed countries (22% versus 57% respectively). Most of the websites (74%) were in English or provided an English version. The most common surveillance methods included influenza-like illness consultation rates in primary care settings (89%) and laboratory surveillance (44%). Most websites (70%) provided data within a static report format and 66% of the websites provided data with at least weekly resolution.

Conclusion: Appropriate dissemination of surveillance data is important to maximize the utility of collected data. There may be room for improvement in the style and content of the dissemination of influenza data to health care professionals and the general public.

Figure 1

Schematic diagram of the course of illness and clinical iceberg of upper respiratory infections in a population, and examples of surveillance systems targeting each stage. The exact proportion of infections falling into each category, and the specificity of surveillance data to influenza will vary at different times and in different settings.

Figure 2

Online influenza surveillance websites worldwide. Nations with influenza or influenza-like illness surveillance websites included in this review are shaded gray. Nations with laboratory influenza surveillance data are shaded black.