Giardiosis

Giardiasis, popularly known as beaver fever, is a parasitic disease caused by Giardia lamblia. About 10% of those infected have no symptoms. When symptoms occur they may include diarrhea, abdominal pain, and weight loss. Vomiting, blood in the stool, and fever are less common. Symptoms usually begin 1 to 3 weeks after exposure and without treatment may last up to six weeks. Giardiasis, popularly known as beaver fever, is a parasitic disease caused by Giardia lamblia. About 10% of those infected have no symptoms. When symptoms occur they may include diarrhea, abdominal pain, and weight loss. Vomiting, blood in the stool, and fever are less common. Symptoms usually begin 1 to 3 weeks after exposure and without treatment may last up to six weeks. Giardia usually spreads when Giardia lamblia cysts within feces contaminate food or water which is then eaten or drunk. It may also spread between people and from other animals. Risk factors include travel in the developing world, changing diapers, eating food without cooking it, and owning a dog. Cysts may survive for nearly three months in cold water. Diagnosis is via stool tests. Prevention is typically by improved hygiene. Those without symptoms do not usually need treatment. When symptoms are present treatment is typically with either tinidazole or metronidazole. People who are not already lactose intolerant may become so temporarily after an infection and therefore it is often recommended milk be avoided for a few weeks. Resistance to treatment may occur. Giardia is one of the most common parasitic human diseases globally. In 2013, there were about 280 million people worldwide with symptomatic giardiasis. Rates are as high as 7% in the developed world and 30% in the developing world. The World Health Organization classified it as a neglected disease. Symptoms vary from none to severe diarrhea with poor absorption of nutrients. Symptoms typically develop 9–15 days after exposure, but may occur as early as one day. The most common and prominent symptom is chronic diarrhea which can occur for weeks or months if untreated. Diarrhea is often greasy and foul-smelling, with a tendency to float. This characteristic diarrhea is often accompanied by a number of other symptoms, including gas, abdominal cramps, and nausea or vomiting. Some people also experience itchy skin, hives, and swelling of the eyes and joints, although these are less common. Prolonged disease is often characterized by diarrhea along with malabsorption of nutrients in the intestine. This malabsorption results in fatty stools, substantial weight loss, and fatigue. Additionally, those suffering from giardiasis often have difficulty absorbing lactose, vitamin A, folate, and vitamin B12. In children, prolonged giardiasis can cause failure to thrive and may impair mental development. Symptomatic infections are well recognized as causing lactose intolerance, which, while usually temporary, may become permanent. Giardiasis is caused by the protozoan Giardia lamblia. The infection occurs in many animals including beavers (hence its nickname), as well as cows, other rodents, and sheep. Animals are believed to play a role in keeping infections present in an environment.