Spirochetal colitis or swine dysentery is a disease of piglets with worldwide distribution. It can cause severe bloody diarrheal disease with a mortality of up to 50% in herds if untreated and thus can have great economic impact. The disease has been nearly eradicated in the US but periodically outbreaks still occur albeit rarely.
An asymptomatic carrier pig can infect a herd but mice may also carry B.hyodysenteriae and be the source of a local epidemic. Diagnosis is not always easy but the organism can be isolated from rectal / fecal cultures. B. hyodysenteriae is an anaerobic hemolysin-producing spirochete.
Treatment consists of rehydration and antibiotics like carbadox, lincomycin, the pleuromutilins tiamulin and valnemulin, or tylvalocin (a macrolide).[1] Carbadox is now banned in many countries because of its carcinogenic potential.[2] Drug resistance has become an issue and pleuromutilins are often necessary as a last resort. However, of great concern are recent reports of B.hyodysenteriae with increased MICs to tiamulin.[3] [4]
Unlike other Brachyspira species, B. h. has not associated been associated with human disease.
P.S. for the philhellenes / φιλέλληνες among you: hys (gen: hyos) = pig !
References:
[1] http://vetmed.iastate.edu/vdpam/new-vdpam-employees/food-supply-veterinary-medicine/swine/swine-diseases/swine-dysentery
[2] http://en.wikipedia.org/wiki/Carbadox
[3] van Duijkeren. J Antimicrob Chemother. 2014 May 3. [Epub]
[4] http://www.thepigsite.com/articles/4507/mic-results-of-brachyspira-hyodysenteriae-strains-recently-isolated-swine-dysentery-outbreaks-in-south-and-south-east-brazil
