by Denice Moffat | Parasitology Section
One wonders why we don’t pick up Toxoplasma more often—especially for those of us who own cats. Could it be that we build up immunity to this organism if our immune system is functioning? It would seem to make sense as serologic surveys show that 7-94% of various populations are infected with the organism and are usually symptomatic. The disease occurs worldwide. If an infection is found, there are antibiotics which can be taken, so early diagnosis is especially urgent for those pregnant or immunocompromised. Children as well are at risk.
by Denice Moffat | Parasitology Section
Microsporidia Spores are oval in shape but are difficult to differentiate from bacteria because they are so small. Identification of spores in feces is actually possible with a modified trichrome stain that stain spores in red. What is Microsporidia? Microsporidia are protozoal parasites of animals and insects responsible for common diseases of crustaceans and fish, and have been found in most other animal groups, including humans. Microsporidia are obligate, intracellular, spore-forming protozoa known to infect many animals. They are very ancient. Intestinal infection with Enterocytozoon bieneusi is increasingly recognized in patients with AIDS and chronic diarrhea where the prevalence is about 23-33%.
by Denice Moffat | Parasitology Section
Giardia cysts on the other hand are very resistant to harsh environmental factors and can survive outside the host for prolonged periods. Giardiasis is most often linked to consumption of contaminated water, but raw produce and other foods have also been considered as possible vectors. Giardia lamblia causes the disease Giardiasis with symptoms of diarrhea, abdominal bloating, stomach cramps, nausea, vomiting, malabsorption syndrome causing steatorrhea (fat in the stool) fatigue and severe weight loss in chronic infections.
by Denice Moffat | Parasitology Section
Symptoms of Amoebiasis: Mucoid or bloody diarrhea, colitis, severe diarrhea with fever, enlarged liver and abdominal pain. The liver can become abscessed if the disease is not treated and can cause death. The incubation period is 2-4 weeks which means you have to be exposed and the parasite needs time to grow before symptoms occur.
by Denice Moffat | Parasitology Section
In 1996, a large outbreak of Cyclospora infection in the United States and Canada was caused by Guatemala-imported raspberries. It is not clear how the fruit became contaminated, but it might have happened when fruit touched the ground or when contaminated water was sprayed over fruit fields by sprinkling systems. People infected with C. cayetanensis excrete oocysts that are not infectious. This is an important clue in diagnosis because other parasitic diseases can be very infectious so more than one person (or pet) in the family will have symptoms at the same time. Cyclospora needs days or weeks after being passed in a bowel movement to become infectious. People most likely get Cyclospora infection by ingesting food or water that was contaminated with stool from an infected person. It is unknown if animals can be infected and pass infection to people.
by Denice Moffat | Parasitology Section
Cryptosporidium is a five micrometer microscopic intracellular protozoal parasite that was first associated with human gastro-intestinal disease in 1976. With the advent of the acquired immunodeficiency syndrome (AIDS) epidemic, Cryptosporidium infections became increasingly recognized as a cause of diarrheal illness.
