International Invention Journal of Medicine and Medical Sciences (ISSN: 2408-7246) Vol. 2(4) pp. 49-55, April, 2015 Available online http://internationalinventjournals.org/journals/IIJMMS Copyright ©2015 International Invention Journals Full Length Research Paper Identification of Pathogenic Intestinal Parasitic Protozoa Associated with Diarrhea among Under-fives Children in Dar Es Salaam, Tanzania Ngosso, B.E. 1 Nkwengulila, G. 2 Namkinga L.A. 1* 1 Department of Molecular Biology and Biotechnology, University of Dar Es Salaam 2 Department of Zoology, University of Dar Es Salaam. Abstract Diarrhea is responsible for high morbidity and mortality among children under the age of five in developing countries. Poor diet and unsafe water supply in households contributes to the prevalence of diarrhea. This study was carried out to determine intestinal parasitic protozoa causing diarrhea. Participants were children under-five years attending Municipal hospitals in Dar Es Salaam with either acute or chronic diarrhea. A total of 720 stool samples were analyzed. Parasitic protozoa were investigated by standard microscopy and PCR methods. The highest prevalence of diarrhea (29.6%) was found in the age groups of 12-23 months, followed by 24-60 months (15.6%), 6-11 months (8%) and least 0-5 months (2.4%). Microscopic method identified 41% parasitic protozoa, PCR 55.6%. However, m-PCR was more discriminative and sensitive, such that the 144 samples identified microscopically as E. histolytica, were differentiated as; E. histolytica 48 (33.3%), E. dispar 80 (55.6%) and E. moshkovskii 16 (11.1%). The most common protozoa were Giardia lamblia 35.6 % (256), followed by Entamoeba histolytica 12.2% (88), Cryptosporidium parvum 7.8 % (56), and Helminthes 12.7% (92). PCR methods should be advocated for differential diagnosis of parasitic causes of diarrhea in Tanzania for children. Key words: Diarrhea, Parasitic protozoa, under-fives. INTRODUCTION Diarrhea is the passage of watery stool for more than three times in twenty-four hours caused by consumption of contaminated food or drinks by a variety of pathogens including bacteria, fungi, viruses, protozoa or helminthes. Diarrhea can also be caused by intolerance to certain types of food or drugs and sometimes stress (Vargas et al., 2004). The disease has remained to be a burden in most developing countries (Reither et al., 2007; Ansari et al., 2012). Furthermore, some underlying conditions that are common in our communities including malnutrition may increase the risk of contracting diarrhea diseases in developing countries. The global deaths due to diarrheal diseases in developed countries had declined steadily due to * Corresponding Author Email: odulajalucy@yahoo.com; Tel: +255 784 772552 advanced health technologies and reliable water supply (Dean et al., 2006; WHO 2013). However, despite of all advances in health technology and improved management, the situation of diarrheal infections in Africa, still remains high, it is the second leading cause of death among the five major killer diseases of children. (UNICEF, 2008; 2012; Quinn 2009; Michael et al., 2010; WGO, 2012 and WHO, 2013). The World Health Organization (WHO, 2013) and the World gastroenterology Organization (WGO) ranks diarrheal disease as the second highest cause of morbidity and mortality in children in the developing world. Knowledge and attitude, and perception of mothers and caregivers on childhood diarrhea plays a major role in the control of childhood diarrhea, as pointed out by Mwambete and Joseph (2010). Diarrhea can be acute watery characterized by abrupt onset of diarrhea of three or more boots of loose stools per day and may last for several hours or days,