Giardiasis : Giardiasis (popularly known as beaver fever is a parasitic disease caused by the flagellate protozoan Giardia lamblia (also sometimes calledGiardia intestinalis and Giardia duodenalis).
Treatment is not always necessary as the infection usually resolves by itself. But in others, the illness is acute or symptoms persist and medications are needed to treat it. Usuallymetronidazole, albendazole, and tinidazole are used.
Amebiasis : Amebiasis is an infection of the intestines caused by the parasite Entamoeba histolytica. Entamoeba histolytica can live in the large intestine (colon) without causing damage to the instestins. However, sometimes, it invades the colon wall, causing colitis, acute dysentery, or long-term (chronic) diarrhea. The infection can also spread through the blood to the liver and, rarely, to the lungs, brain, or other organs.
This condition occurs worldwide, but it is most common in tropical areas with crowded living conditions and poor sanitation. Entamoeba histolytica is spread through food or water contaminated with stools. This contamination is common when human waste is used as fertilizer. It can also be spread from person to person -- particularly by contact with the mouth or rectal area of an infected person.
Risk factors for severe amebiasis include:
• Alcoholism
• Cancer
• Malnutrition
• Older or younger age
• Pregnancy
• Recent travel to a tropical region
• Use of corticosteroid medication to suppress the immune system
Symptoms
Mild symptoms:
• Abdominal cramps
• Diarrhea
o Passage of 3 - 8 semiformed stools per day
o Passage of soft stools with mucus and occasional blood
• Fatigue
• Excessive gas
• Rectal pain while having a bowel movement (tenesmus)
• Unintentional weight loss
Severe symptoms:
• Abdominal tenderness
• Bloody stools
o Passage of liquid stools with streaks of blood
o Passage of 10 - 20 stools per day
• Fever
• Vomiting
Treatment
• Treatment depends on the severity of infection. Usually, metronidazole is given by mouth for 10 days. This is followed by paromomycin or diloxanide.