Smallpox and its eradication in the Democratic Republic of Congo: lessons learned.

Smallpox eradication is considered to be one of the most remarkable accomplishments of the 20th century. Lessons learned from the campaign during the 1960s and 1970s in the Democratic Republic of Congo (DRC) can provide important information for the development of other eradication programs including polio. The DRC is the third largest country in Africa; the population suffers from extreme poverty, deteriorating infrastructure and health systems, and long periods of civil strife. Despite these challenges, DRC's smallpox eradication campaign was successful, eradicating smallpox only 41 months after initiation. DRC had been polio free since 2001; however, in 2006, imported cases were identified in the country. Polio transmission has since been re-established and DRC now has the second greatest number of reported polio cases in the world. Challenges which existed during the smallpox campaign in DRC are still present today; additionally, the polio vaccine itself poses unique challenges which include requiring multiple doses to confer immunity. In the fight against polio in DRC, it will be important to draw from the smallpox eradication experience. A number of important themes emerged during the campaign that could be beneficial to eradicating polio and future eradication programs that may follow. During the smallpox campaign, a standard vaccination program was implemented, surveillance was intensified, and there were strong collaborative programs with community involvement. These successful elements of the smallpox campaign should be adapted and applied in DRC in polio eradication programs.