(Examiner) Top 5:
1. Giardia intestinalis – A parasite known as Giardia intestinalis is the cause of the infection. The parasite is transmitted from contaminated food with feces. Another source of infection is drinking water. This parasite survives outside the body because it forms into a cyst, which is tolerant to chlorination.The infection causes diarrhea.
2. Shigella – the organism that causes diarrhea in humans is termed Shigella. This germ is transmitted from one person to the next. The bacterium was discovered over 100 years ago by a Japanese scientist, whose name was Shiga, and thus the organism name. There are several species of Shigella; Shigella sonnei belongs to group D, and is responsible for over 2/3 of infections in the United States. Shigella flexneri, or group B causes the other infections. Shigella dysenteriae type 1, can cause epidemics up to and including death.
3. Hepatitis A – the infection known as Hepatitis refers to a viral infection that infects the liver. The types of infections are Hepatitis A, B, C, D, and E. Hepatitis can cause cancer in the liver and, a liver transplant may be necessary. Hepatitis A is an acute infection which does not lead to chronic. It is transmitted by contaminated food or drink with fecal matter. Prevention includes vaccination.
4. Norovirus – A virus known as Norovirus can cause acute gastroenteritis in man. It belongs to the genus Norovirus, and is a single stranded RNA virus.The symptoms include diarrhea, vomiting, and pain in the stomach. The disease may be spread by person to person, contaminated food or water, and surfaces. There is not treatment for noroviruses.
5. Copper – this is an element essential to life. Low levels are required by humans to survive. High levels can cause harm.