[Cholera in Senegal from 2004 to 2006: lessons learned from successive outbreaks]. / Le choléra au Senegal de 2004 à 2006: les enseignements d'épidémies successives.

ABSTRACT

Between October 2004 and March 2006, a series of cholera outbreaks occurred in the West African nation of Senegal. The purpose of this study was to describe and analyze these outbreaks as a basis for prevention and control. A total of 29556 cases were reported during the 18-month epidemic. The attack rate ranged from 0.6 to 100 per 10(4) inhabitants depending on region. The epidemic unfolded in three phases. The first phase (11 weeks) was promptly contained using basic control measures such as public information campaigns and environmental hygiene. The second and longest phase (12 months) was marked by two outbreaks caused by massive religious gatherings and severe flooding. Cities particularly the capital Dakar (25.5% of cases) and the religious district of Touba in the north (41.1% of cases) were most affected due to the many social and environmental problems related to poor urban infrastructure. The isolated strains of Vibrio cholerae O1, biotype El Tor, were susceptible to doxycycline and fluoroquinolones (100%) but resistant to cotrimoxazole (90.3%). The overall death rate was 1.38%. Unfavorable prognostic factors included age over 60 years, delayed treatment and severe dehydration at the time of admission. Despite lower mortality this cholera epidemic was more widespread and longer than the previous outbreaks in Senegal and was associated with a trend to endemicity in urban areas.