From Today's New York Times

To the Editor:

Re “Ebola Imperils Gorilla Species in Congo Republic” (news article, Dec. 8):

Increasingly, we are observing that our efforts to reach sustainable balances for wildlife populations are being confounded by the spread of infectious disease. Historically, these diseases have been studied only when they affect human populations or domestic animals.

In 2003, I was in the sanctuary described in your article and collected samples from those dead animals.

Whether it is the Ebola virus in gorillas, the H5N1 avian influenza virus in birds or SARS, we are understanding that the implications of infectious disease for wildlife and humans are becoming one and the same.

As we continue to exert pressure on wildlife and wild lands, health issues are hitting us from a number of angles and reminding us that while animal health and human health are separated because of academic tradition, there is really only one world and only one health.

William B. Karesh
Bronx, Dec. 8, 2006
The writer is director of the Field Veterinary Program, Wildlife Conservation Society.