Society today has become overly sterilized. Antibiotic hand soaps and disinfectants can be found in many American households and business and it seems that people are increasingly afraid of getting "dirty". This trend has become severe enough that in the late 1980's Dr. Strachan formulated the "Hygiene Hypothesis", which suggests that a decrease in exposure to infectious agents causes an increase in atopic diseases . A good way for people, especially children, to become exposed to microorganisms is for them to eat food that has been on the ground since there can be up to 2,000 bacterial species in half a gram of Minnesotan soil . That being said there are times when eating the cookie that fell on the ground is a very bad idea. One of the worst times for this would be when there is a chance that raccoons have recently defecated on that spot. The ingestion of raccoon fecal matter should be avoided because raccoons are the definitive host for Baylisascaris procyonis. More commonly known as the raccoon roundworm B. procyonis is a helminth that can be found in up to 70% of raccoons and can cause severe disease in humans .
Figure 1. Basic diagram of the B. procyonis
lifecycle, including other host organisms.
Figure 2. Adult worms next to a
dime for scale. The size of the
worms is part of the reason for
the disease severity and neurological
complications. Female worm is
on left, male is on right.
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