Epidemiology and Infection

Research Article

Epidemic cholera in rural El Salvador: risk factors in a region covered by a cholera prevention campaign

R. E. Quicka1, B. L. Thompsona1, A. Zunigaa3, G. Domingueza3, E. L. De Brizuelaa3, O. De Palmaa3, S. Almeidaa3, A. Valenciaa4, A. A. Riesa2, N. H. Beana2 and P. A. Blakea2

a1 Division of Field Epidemiology, Epidemiology Program Office

a2 Foodborne and Diarrheal Diseases Branch, Division of Bacterial and Mycotic Diseases, National Center for Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA 30333

a3 Ministry of Public Health and Social Assistance

a4 Pan American Health Organization, San Salvador, El Salvador


In response to the Latin American cholera epidemic, El Salvador began a prevention programme in April 1991. The first case was confirmed in August, and 700 cases were reported within 3 months. A matched case-control study was conducted in rural La Libertad Department in November 1991. Illness was associated with eating cold cooked or raw seafood (odds ratio [OR] = 7·0; 95% confidence limits [CL] = 1·4, 35·0) and with drinking water outside the home (OR = 8·8; 95% CL = 1·7, 44·6). Assertion of knowledge about how to prevent cholera (OR = 0·2; 95% CL = 0·1, 0·8) and eating rice (OR = 0·2; 95% CL = 0·1, 0·8) were protective. More controls than patients regularly used soap (OR = 0·3; 95% CL = 0·1, 1·0). This study demonstrated three important points for cholera prevention: (1) seafood should be eaten cooked and hot; (2) populations at risk should be taught to treat household drinking water and to avoid drinking water outside the home unless it is known to be treated; and (3) education about hygiene can be an important tool in preventing cholera.

(Accepted August 18 1994)