Polycystic kidney disease can cause abdominal pain, headaches, and pain in the sides and back. Porphyria is a condition that can affect the nerves and skin, making the skin extremely sensitive to sunlight. Hydronephrosis is a condition of the kidneys and causes aching or pain, urinary symptoms, fever, and nausea.
Protozoan infections are parasitic diseases caused by organisms formerly classified in the Kingdom Protozoa. They include organisms classified in Amoebozoa, Excavata, and Chromalveolata. Examples include Entamoeba histolytica, Plasmodium (some of which cause malaria), and Giardia lamblia. Trypanosoma brucei, transmitted by the tsetse fly and the cause of African sleeping sickness, is another example.
Diseases caused by the single-celled protozoans include amoebic dysentery, babesiosis, cryptosporidiosis, intestinal giardiasis, malaria, and vaginal trichomoniasis. Viral: The most common type of infectious disease that humans are susceptible to are viral. Viruses cause a host of diseases and are tinier than bacteria as well. The most frequent disease that constantly affects humans on a day-to-day basis is the common cold, caused due to a viral infection.