Many children around the world , especially in third world countries suffer many bacterial infection of the gastrointestinal system as a result of lack of awareness and the spread of the disease in the less attention to hygiene and the environment . In order to explain this word gastrointestinal tract infection , especially the stomach and intestines , it can result from infection by bacteria or virus or other parasites (1) . Some of the causes of inflammation as a result of eating food poisoning , especially meat and eggs . However , some symptoms of severe cases are headache , nausea , vomiting , general weakness , diarrhea and pain , the illness begins suddenly with high fever , vomiting , abdominal pain and stool liquid to water that may contain some blood and mucus . The result of drought through loss of fluids and salts and lead an alliance with the poisoning to the collapse of the circulatory system in diseases such as cholera (2) . It must be conducted in diagnosing bacterial to find the source of infection because it causes illness and death of millions in the third world and in particularly children as mentioned . In this report will refer to the most common types of bacteria cause gastrointestinal tract infection for example , Shigella , Salmonella , Vibrio and Campylobacter (3) . First of all , Shigella is gram negative , nonmotile , non lactose fermenting and H2S production . There are four important species , S. sonnei , S. flexneri , S. boydii and S. dysenteriae is the most serious . Next is Salmonella which is gram negative as well , non lactose fermenting and production H2S . These species are S. typhi and S. paratyphi found in humans and animals . Finally , Campylobacter is gram negative bacilli , curved or S shape and motile by flagella , most important are C. jejuni , C. coli and C. upsaliensis . Whilst , the report will mention quickly about the genus Vibrio , three species are very important humans disease , V. cholerae , V. parahaemolyticus and V. vulnificus . They are also gram negative , positive to oxidase , motile , comma shape . This aims of these exercises are to identify these examinations and will prove some non pathogenic bacteria in gastrointestinal tract as considered normal flora. Although , some of them are considered pathogenic organisms for example , parasites , viruses and bacteria as well which can cause many human infections . In addition , using many techniques to identify these bacteria Shigella , Salmonella , Vibrio and Campylobacter as mentioned (4) .
Case study 1:
72 patients according to practical manual of Medical Microbiology were suffered many symptoms such as , headaches , diarrhea and vomiting without blood as a result of eating grilled chicken as well as some patients entered the hospital for treatment . The specimens were sent to the laboratory...