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Last Updated

30 Mar 2003

Source: Washington Times, March 30, 2003


Emerging threats

It starts with what seems the most inconsequential of actions a sniff, a stifled cough, a sneeze. It is only afterward a few days or a few weeks that the event is seen in a far more sinister light, as the start of an epidemic, the emergence of a new disease.

Such diseases, whether Severe Acute Respiratory Syndrome (SARS), West Nile virus encephalitis or even AIDS, pose a chronic, costly public-health threat that must be constantly monitored particularly given the threat posed by bioterrorism. As it stands, the cost of infectious diseases is staggering. In the United States, the direct and indirect costs from infectious disease are estimated at more than $120 billion per year. Across the globe, these diseases kill more than 13 million individuals each year, according to the World Health Organization (WHO).

A rogue's laboratory is only one place from which agents of infection can emerge. So-called superbugs, resistant to several kinds of antibiotics, can emerge as a consequence of evolution coupled with the use of antibiotics. Multi-drug resistant tuberculosis is one example. Diseases can emerge as zoonoses animal diseases that cross to humans. Perhaps the best-known example is the human immunodeficiency virus (HIV). They can emerge as new forms of known pathogens, as in the case of influenza, the virus that causes the flu. The agent(s) responsible for SARS are apparently new members of known viral families.

Other ailments are certain to follow SARS. Several factors have increased the incidence and spread of emergent diseases, including the acceleration of urbanization; the movement of humans into new habitats; the wide use of antibiotics; changes in social and behavioral patterns; and globalization, according to a recent Rand Institute study, "The Global Threat of New and Reemerging Infectious Diseases: Reconciling U.S. National Security and Public Health Policy." Thanks to the modern speed of travel, emergent diseases can cross continents and oceans in a matter of hours, this helps explain why, on Thursday, WHO urged airlines to screen passengers for the deadly flulike SARS.

Yet, there is always a lag between the discovery of a new disease and the identification of the agent that causes it. For many diseases, there's even a longer lag between the identification the disease and the discovery of an effective treatment or cure. Treatments for AIDS are still being worked on, the reservoir of the Ebola virus has still not been determined and the anthrax mailer is still at large.

Constant, active surveillance is critical in this regard. However, the United States has a long way to go. The Rand study pointed out that state disease reporting to the CDC is done on a voluntary basis, and that, as a result, 90 percent of U.S. states and territories reported just 60 percent of 19 notifiable diseases in 1999. Rand authors also suggest that coordination and information sharing among public-health authorities continue to be improved.

Information sharing is also critical to controlling emerging diseases. While the CDC and the WHO have done an exemplary job during the SARS outbreak, the Chinese government has much to answer for literally. It took Beijing nearly four months to formally request help from WHO. Twice it has turned away WHO investigation teams attempting to visit Guangdong Province, where the virus reportedly originated. It has yet to reveal everything it knows about the outbreak.

Accordingly, the U.S. government must begin to prepare for the next outbreak by developing more antivirals and antimicrobials, among other measures. Unfortunately, "only four large pharmaceutical companies with antibiotic research programs remained in existence in 2002 and not one new class of antibiotics is in advanced development," according to a recent study from the National Academy of Sciences.

Vaccination programs, including the lagging smallpox program, should also be advanced and the timelines accelerated so that those in the public who wish to volunteer for such inoculations are able to receive them.

Ultimately, diseases are no more likely to stop emerging than individuals are to stop sneezing. SARS is a portent of others. Even though the war in Iraq is still raging and the epidemic of SARS is still burning, the government should continue to prepare for the next emerging disease.