Early Warning: The Necessary Beginning

Department of Epidemiology, Columbia University


Although most infections have been with us for a long time, new infections enter the human population or rapidly spread from a geographically limited area. Infections that appear suddenly or rapidly increase in number of cases or geographic range, are often called “emerging infections.” Examples include human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS), SARS (Severe Acute Respiratory Syndrome), Nipah, and pandemic influenza (H1N1-2009). Early warning surveillance is essential if we wish to prevent currently existing infectious diseases from increasing their range, or to prevent the next pandemic. But we do not currently have adequate capabilities in place at virtually any level. While the scientific issues are complex, I believe we have the scientific framework to begin, and that recent technological/scientific advances make this an opportune time to attack this problem. Recommendations include: the need to develop capability both to identify (and rule out) common infectious diseases, as well as the unexpected or unusual; implementing the revised International Health Regulations; coordinating reporting systems and enhancing data sharing; encouraging interagency cooperation; maintaining personnel; strengthening research to refine microbial risk assessment and triggers for action, and continuing to educate policy makers on the importance of early warning surveillance.