intestinal phases of Toxoplasma gondii, including "banana bunch" schizonts (upper right and elsewhere) and trophozoites (upper left with prominent nucleus and small clear area around it).  This is a feline parasite and this section is probably from a kitten.  Humans become infected either through cat feces or eating raw or poorly cooked meat.  The incidence of infection is quite high in many countries, such as France where steak tartare is relished.  1000x
"banana bunch" schizont with trophozoite of T. gondii below and slightly to the right.  Toxoplasma gondii is one of the most common causes of congenital birth defects.  Previously-uninfected women should never handle outdoor cats (those that eat rodents) or eat raw meat.  Primary infections occurring during pregnancy present the principle risk.  Women, already infected prior to the pregnancy, pose no known risk to the developing fetus.  1000x