The Occurrence of Cryptosporidium and Giardia Infections Among Patients Reporting Diarrheal Disease in Chobe District, Botswana

摘要

Diarrheal disease is a chronic public health problem in Chobe District, Botswana. Acute diarrheal outbreaks occur annually with a bimodal seasonal pattern coinciding with major hydrological phenomena. Information is lacking regarding the etiology of reoccurring outbreaks. Cryptosporidium and Giardia are recognized as important waterborne causes of diarrheal disease with Cryptosporidium transmission potentially involving zoonotic reservoirs. In Chobe District, municipal water is obtained from the Chobe River after it exits the Chobe National Park where high concentrations of wildlife occur. Using the Giardia/Cryptosporidium QUIK CHEK rapid antigen cartridge test, we evaluate the occurrence of Giardia and Cryptosporidium among patients (n = 153) presenting to medical facilities in Chobe District with diarrhea (August 2011-July 2012). Cryptosporidium was only identified in children less than two years of age (10%, n = 42, 95% CI 3% - 23%), with positive cases occurring during diarrheal outbreak periods. Infections were not identified in adults despite the high level of human immunodeficiency virus infection/acquired immunodeficiency syndrome (HIV/AIDS) in the region (n = 117). Although not significant, cases were predominately identified in the wet season outbreak (p = 0.94, 25%, n = 12, 95% CI 5% - 57%, dry season outbreaks 3%, n = 30, CI 95% 0% - 17%). Giardia infections occurred across age groups and seasons (7%, n = 153, 95% CI 4% - 10%). This is the first published report of human infections with Cryptosporidium and Giardia in this area of Africa. This study suggests that Cryptosporidium may be a potentially important cause of diarrheal disease in children less than 2 years of age in this region. Further research is required to identify pathogen transmission and persistence dynamics and public health implications, particularly the role of HIV/AIDS and vulnerability to waterborne disease.