Giardiasis is passed via the fecal-oral route. Primary routes are personal contact and contaminated water and food. The more susceptible are institutional or day-care workers, travelers, those eating improperly treated food or drink, and people who have contact with individuals already infected.
Giardia are flagellate protozoa that cause giardiasis. The parasite attaches to the epithelium by a ventral adhesive disc and reproduces through binary fission. It absorbs the nutrients from the lumen of the small intestine. It does not spread, but rather stays confined to the lumen of the small intestine. Colonization of the gut results in inflammation and villus atrophy, reducing the guts absorptive capability.
Symptoms include loss of appetite, diarrhea, hematuria (blood in urine), loose or watery stool, stomach cramps, upset stomach, projectile vomiting (uncommon), bloating, excessive gas, and burping (often sulfurous).
It is caused by gloating in the intestine
Scientific name: Flagellate protozoa
It is common in Africa.
It is mainly passed by blood-feeding invertebrates but there are different ways also. In an invertebrate host they are generally found in the intestine, but normally occupy the bloodstream or an intracellular environment in the host. It is caused by the infection with protozoan parasites. They are transmitted to humans by tsetse fly bites. Other ways to spread:
- Mother-to-child infection: the trypanosome can cross the placenta and infect the fetus.
- Mechanical transmission through other blood sucking insects is possible.
- Accidental infections have occurred in laboratories due to pricks from contaminated needles.
The symptoms occur in 2 stages. In the 1st stage, the trypanosomes multiply in subcutaneous tissues, blood and lymph. This is known as a first stage or haemolymphatic phase, which entails bouts of fever, headaches, joint pains and itching. In the second stage the parasites cross the blood-brain barrier to infect the central nervous system. Things like changes of behaviour, confusion, sensory disturbances and poor coordination, and disturbance of the sleep cycle
Scientific name: Plasmodium falciparum
Malaria is caused by the protozoan parasite Plasmodium. The malaria parasite is transmitted by female Anopheles mosquitoes, which bite mainly between dusk and dawn. Malaria is common in tropical and subtropical regions because rainfall, warm temperatures, and stagnant waters provide an environment ideal for mosquito larvae
Symptoms include may include headache, fever, shivering, joint pain, vomiting, hemolytic anemia, jaundice, hemoglobin in the urine, retinal damage, and convulsions. Individuals with cerebral malaria frequently exhibit neurological symptoms, including abnormal posturing, nystagmus, conjugate gaze palsy, opisthotonus, seizures, or coma.
Also known by its scientific name: Entamoeba histolytics
Common name: Ameba
Entamoeba is a genus of Amoebozoa found as internal parasites or commensals of animals. Transmission of the parasite occurs when a person ingests food/water that has been contaminated with infected feces
Symptoms include fulminating dysentery, bloody diarrhea, weight loss, fatigue, abdominal pain, and amoeboma.