How common is giardiasis?
Giardiasis is found throughout the U.S. High rates of infection have been documented among children in day care centers, institutions, and on Native American reservations. Outbreaks occur most commonly from July through October. In some parts of the world, especially in developing countries, giardiasis is an endemic disease ( that is, the virus is constantly present with low levels of infection ). In these areas, many infected persons may have no signs of illness, even though they carry the parasite.
