Haddon matrix could help public health officials tackle an influenza pandemic

A tool developed in the 1960s for preventing road traffic injuries could help in preparing for the next influenza pandemic, say researchers in the open access journal PLoS Medicine.

The prospect of a pandemic with avian influenza is an urgent concern for public health leaders worldwide, and yet in most countries pandemic influenza plans are only in a draft form and lack legal status. The researchers say that the "Haddon matrix," a tool developed by Dr William Haddon Jr. for improving traffic safety, could help public health officials tackle the challenges of an influenza pandemic.

The original 1960s matrix is a grid that breaks down a road traffic injury into the various factors that contributed to the injury before, during, and after the event. The researchers have adapted this matrix into a tool to help divide the complex problem of influenza planning into more manageable segments. Using the matrix, they say, allows health planners to select policies or actions with the greatest feasibility or influence.

The researchers--led by Dr Daniel Barnett at the Johns Hopkins Center for Public Health Preparedness, United States, and Dr Ran Balicer at Ben-Gurion University of the Negev, Israel--show how the tool can be adapted to local conditions in different countries.

For example, they use the tool to analyze Thailand's recent experience in controlling the human spread of H5N1 influenza infection. By October 2004, 17 patients with the infection had been identified, of whom 12 had died, but there were no human cases between October 2004 and August 2005.

"Through the lens of the pre-event Haddon matrix factors," they say, "one can identify the strengths in Thailand's preparedness efforts, as well as opportunities for further enhancements." Some of the strengths identified by the matrix include a nationwide influenza surveillance campaign, which started in October 2004, as well as Thailand's recent decision to test H5N1 vaccines in "open range" poultry (i.e. non-commercial poultry, such as backyard poultry and free-range ducks).

The planning window for an influenza pandemic "may be rapidly closing," say the researchers. "As an efficient yet comprehensive analytic approach, the Haddon matrix lends itself to the types of rapid and complex decision making necessary to plan for and respond more effectively to an urgent pandemic health threat."