outbreak—the public health laboratory network for cholera has confirmed the results obtained through the mandatory notification process.

At present, the surveillance system in Argentina includes three components: (1) physicians at the first health care level (sentinels), (2) public health laboratories distributed throughout the country, and (3) provincial epidemiology units that analyze the collected data. Applied research and quality assurance processes—directed to increasing the specificity of epidemiological surveillance— occupy a central role in the organization of the 650 laboratories in the Argentine network.

Argentine hemorrhagic fever (AHF) has been a major public health concern since 1955. It is an acute viral disease caused by the Junin virus, an arenavirus, and it is endemic to the Argentine humid pampa. An increased incidence of AHF has been observed among adult rural workers, reflecting occupational exposure to the virus. The focal incidence of AHF correlates well with the distribution of the rodent reservoirs. The affected area has gradually been extending and now covers approximately 150,000 square kilometers (58,000 square miles), including densely populated areas in the Department Rosario in the province of Santa Fe. The population at risk is approximately 5 million. AHF has shown 5-year cycles, likely related to fluctuations in the densities of rodent populations.

Because the control of rodent reservoirs of the Junin virus is not feasible in such an extended geographical area, most preventive efforts have been directed to vaccine development. The development of a vaccine against AHF has a long history. In a first stage (1968–1969), a live, attenuated, cloned virus vaccine, XJ Clon 3, was developed in the Faculty of Medicine at the University of Buenos Aires (Weissenbacher et al., 1969) and was tested successfully in 300 volunteers. In a second stage, a clone from the Junin virus formed the Candid 1 vaccine, developed as a result of an international cooperative project between the U.S. Army Medical Research Institute of Infectious Diseases (USAMRIID), PAHO, and the Argentine Ministry of Health. Between 1985 and 1990 a vaccine trial involving more than 7,000 volunteers in Argentina established the immunogenicity, inoculability, and efficacy (95.5 percent) of the Candid 1vaccine.

The vaccine was readily accepted by the population, which was significant considering that vaccination was voluntary, experimental, restricted geographically, required an informed consent as well as a pregnancy blood test for women of reproductive age, and required travel to designated vaccination posts, which were open only on certain fixed days at fixed times (Enria et al., 1998).

The Candid 1 vaccine is highly effective; it elicits high levels of protective antibodies for 9 years after vaccination in approximately 90 percent of people vaccinated with a single dose. However, AHF is not an eradicable disease, and despite good vaccine coverage rates, isolated cases and limited outbreaks will likely occur

Front Matter (R1-R16)

Summary and Assessment (1-28)

Introduction (29-34)

Emerging Infections in Latin America (35-51)

Emerging Infections in Africa (52-61)

Emerging Infections in Asia and the Pacific (62-71)

Emerging Infections in Europe (72-84)

References (85-86)

Appendix A: Glossary and Acronyms (87-94)

Appendix B: Workshop Agenda (95-99)

Appendix C: Workshop Participants (100-106)

Appendix D: Forum Member and Staff Biographies (107-118)