In November 2007 a novel neuropathy, immune-mediated
polyradiculoneuropathy (IP), was identified among
workers at a Minnesota swine abattoir where a unique
compressed air technique was used to remove porcine
brains. An epidemiologic investigation at another abattoir
in Indiana that also uses this process was launched to
evaluate workers self-reporting neurologic illness compatible
with IP. A nested case-control study was performed
to identify cases and risk factors. Six confirmed,
one probable, and three possible IP cases were detected.
IP cases were 28–52 years old, of Latino origin, and
62.5% female. Onset dates ranged from April
2005–December 2007; 60% were hospitalized. IP cases at
this plant were similar in clinical presentation and exposure
risks to those detected in Minnesota. Swine abattoirs
using similar brain extraction methods should discontinue
this process.