If you write about zoonotic and emerging diseases, you'll find a free subscription to ProMED-mail  — the Program for Monitoring Emerging Diseases — valuable.
This online reporting system rapidly disseminates global information on "outbreaks of infectious diseases and acute exposures to toxins that affect human health, including those in animals and in plants grown for food or animal feed. Electronic communications enable ProMED-mail to provide up-to-date and reliable news about threats to human, animal, and food plant health around the world, seven days a week."
ProMED-mail, a program of the International Society for Infectious Diseases, is non-partisan and open to all sources, which include media reports, official reports, online summaries, local observers, ProMED-mail subscribers, and more. All reports are reviewed by expert human, plant, and animal disease moderators before they're posted to the network. Reports are emailed to list subscribers and posted on the ProMED-mail website. As at Dec 2010, ProMED-mail has 40,000 subscribers in 185 countries.
ProMED-mail lists are also available in Portuguese and Spanish, for Portuguese- and Spanish-speaking countries in Latin America, respectively, as well as in Russian for reports relevant to the independent states of the former Soviet Union. Another list provides reports in English on countries in Southeast Asia bordering the Mekong River. Under a grant from Google.org, ProMED-mail is working to enlarge networks in Francophone Africa (posted in French) and Anglophone Africa (posted in English).