Trichuris suis

TRICHURIS SUIS

• A typical whipworm.
• Prefers warmer climates and therefore only rarely a problem in the UK.
• Disease mainly seen in pigs kept outdoors or in deep-litter systems.

Pathogenesis

• Can provoke severe diarrhoea or dysentery by providing a portal of entry for microbial organisms (particularly spirochaetes).

Use in Human Medicine

• In experimental models, Trichuris markedly increases T-regulatory activity, thereby suppressing some immune-mediated diseases (Th2 responses increased; Th1 responses decreased).
• There's a theory that some human immune-mediated diseases are largely restricted to affluent developed countries (like inflammatory bowel disease and Crohn's disease) occur because the human immune system has evolved with T-regulating helminths constantly present, and therefore tends to go into overdrive in some individuals if this external regulatory influence is lacking.
• This had led to the hypothesis that strictly controlled exposure of selected human patients to T. suis might ameliorate the symptoms of chronic bowel disease.
• Large scale clinical trials (placebo-controlled cross-over studies) are currently in progress to test this hypothesis.