Smallpox and Its Eradication in Finland: Implications for Disease Control

Abstract

Cause-specific mortality studies are vital for a full understanding of the determinants of mortality and epidemiological transitions. The exceptional detail and accuracy of archival materials in Finland, as well as the length of the period covered, offer an ideal opportunity for such analyses. Focussing upon the late nineteenth and early twentieth centuries, the history, decline, and eventual eradication of smallpox is detailed. It has often been argued that primary vaccination in childhood was the major factor responsible for the decline and subsequent elimination of the disease in Finland. This perspective is probably correct for the initial decrease in smallpox mortality. To interpret the final phases of smallpox history in Finland, however, several factors must be taken into consideration. These include revaccination, virulence of the virus, containment (quarantine) of infected individuals, vaccination of contacts, and importation of the virus from surrounding countries. While these factors were not of equal causal importance, they exerted a synergistic effect on the course of Finnish smallpox history. This in-depth historical case study demonstrates that multiple factors must be taken into account when disease control policies in developing countries are formulated to-day.