Objectives: In 2017, a total of 889854 suspected cholera cases with 2578 deaths were reported from Yemen, thus WHO considered these figures to be the worst epidemic of cholera in recent history of humanity. The aims of the study were to determine the prevalence of Vibrio cholera and protozoa causes in severe diarrhea patients and the potential risk factors of the contracting Vibrio cholera. Methods: Hospital-based diarrhoeal disease surveillance has been done for 12 days in Bany-alharth district of Sana'a city, where all patients admitted with severe diarrhoea in all health centers in the area were enrolled and tested for Vibrio cholerae, and others causes. The study was conducted on 345 patients and demographic, clinical, and potential risk factors were collected, then stool specimens were collected and processed by standard methods. Results: The prevalence of V. cholerae was 8.1%, intestinal Entamoeba histolytica was 50.7%, and Giardia lamblia was 6.7% and one case of EPEC while 42% of diarrheal cases were undiagnosed. There was slightly increasing in the rate of V. cholerae infection with increasing age (15%). Also there were significant risk factors of dispose sewages to surround environment (OR=3.4 times, PV=0.02) and reused Jerry can bottles for drinking water (OR=3.1, PV= 0.03) with V.cholerae infection Vibrio cholera infection rate and intestinal protozoa infection rates were significantly high. Conclusion: The findings emphasize that there is cholera epidemic in Sana' city and diarrheal epidemic due to various diagnosed and non diagnosed pathogenic microorganisms which may predispose population of the study to significant health risks. Peer Review History: Received 26 November 2017; Revised 10 December; Accepted 18 December, Available online 15 January 2018 UJPR follows the most transparent and toughest ‘Advanced OPEN peer review’ system. The identity of the authors and, reviewers will be known to each other. This transparent process will help to eradicate any possible malicious/purposeful interference by any person (publishing staff, reviewer, editor, author, etc) during peer review. As a result of this unique system, all reviewers will get their due recognition and respect, once their names are published in the papers. We expect that, by publishing peer review reports with published papers, will be helpful to many authors for drafting their article according to the specifications. Auhors will remove any error of their article and they will improve their article(s) according to the previous reports displayed with published article(s). The main purpose of it is ‘to improve the quality of a candidate manuscript’. Our reviewers check the ‘strength and weakness of a manuscript honestly’. There will increase in the perfection, and transparency. Received file: Reviewer's Comments: Average Peer review marks at initial stage: 5.5/10 Average Peer review marks at publication stage: 8.0/10 Reviewer(s) detail: Prof. Dr. Kaijian Hou, Endocrine Department, Longhu, First Affiliated Hospital of Shantou University, Shantou city, PR China, kaijianhou@126.com Dina Abd Elfattah Eldakhs, Pharos university (PUA), Egypt, dina_eldakhs@yahoo.com Similar Articles: ANTI-DIARRHEAL ACTIVITY OF ETHANOL AND CHLOROFORM SEED EXTRACT OF COLA NITIDA IN EXPERIMENTALLY INDUCED DIARRHEA