Characteristics of All Study Participants (n = 175).

<p>Characteristics of All Study Participants (n = 175).</p

Venn Diagrams Illustrating the Challenges of Defining or Categorizing Exposures.

<p><b>a) Numbers of Male Farmers Who Reported Working with Swine, Cattle, and Chickens in 2006.</b> A total of 95 out of 126 male farmers reported working with animals in 2006. This diagram includes 92 of these farmers and excludes three farmers who reported working only with other animals. A total of 54 male farmers reported working with swine, 61 reported working with cattle, and 26 reported working with chickens. The overlap between these categories is illustrated in the Fig Circles are not drawn to scale. <b>b) Numbers of Male Farmers Who Reported Working with Swine, Cattle, Chickens, and Other Animals in 2006.</b> A total of 95 out of 126 male farmers reported working with animals in 2006: 54 reported working with swine, 61 reported working with cattle, 26 reported working with chickens, and 38 reported working with other animals. The overlap between these categories is illustrated in the Fig, which is not drawn to scale. “Other animals” includes horses (n = 20), sheep (n = 17), poultry other than chickens (n = 6), goats (n = 6), and other animals (n = 6), with some farmers reporting working with more than one type of other animal. <b>c) Numbers of Male Farmers Who Reported Ever Working With Swine, Cattle, Chickens, and Other Animals.</b> This diagram includes all 126 male farmers who reported ever working with animals. Of these, 125 reported working with swine, 64 reported working with cattle, 62 reported working with chickens, and 60 reported working with other animals. The overlap between these categories is illustrated in the Fig, which is not drawn to scale. “Other animals” includes horses (n = 32), sheep (n = 38), poultry other than chickens (n = 12), goats (n = 6), and other animals (n = 11), with some farmers reporting working with more than one type of other animal.</p

Difference in Anti-<i>C</i>. <i>jejuni</i> Optical Density Ratio Distribution Between Farmers and Controls by Age Category (n = 175).

<p>Difference in Anti-<i>C</i>. <i>jejuni</i> Optical Density Ratio Distribution Between Farmers and Controls by Age Category (n = 175).</p

Anti-<i>Campylobacter jejuni</i> Antibodies: Farmers vs. Controls (n = 175).

<p>Anti-<i>Campylobacter jejuni</i> Antibodies: Farmers vs. Controls (n = 175).</p

Anti-<i>C</i>. <i>jejuni</i> Antibody Optical Density Ratios for Farmers Compared to Controls: a) IgA; b) IgG; c) IgM.

<p>Anti-<i>C</i>. <i>jejuni</i> Antibody Optical Density Ratios for Farmers Compared to Controls: a) IgA; b) IgG; c) IgM.</p

Study Population.

<p>AHS = Agricultural Health Study.</p

Anti-<i>C</i>. <i>jejuni</i> Antibody Optical Density Ratios (ODR) by Animal Herd or Flock Size in 2005–2006 for Male AHS Farmers.

<p>Anti-<i>C</i>. <i>jejuni</i> Antibody Optical Density Ratios (ODR) by Animal Herd or Flock Size in 2005–2006 for Male AHS Farmers.</p

Schematic Depiction of Hypothesized Causal Pathway Between Occupational Exposure to Poultry, Swine, or Cattle and Development of Autoimmune Peripheral Neuropathy.

<p>Farmers and others who work with animals may be occupationally exposed to the avian commensal bacterium <i>Campylobacter jejuni</i>, which may result in infection and immune response. Molecular mimicry, or similarity in structure, between lipo-oligosaccharides (LOS) of <i>C</i>. <i>jejuni</i> bacteria and epitopes of human gangliosides may lead to the proliferation of anti-ganglioside autoantibodies and subsequent symptoms of autoimmune peripheral neuropathy.</p

Anti-ganglioside Autoantibodies: Farmers vs. Controls (n = 173)*.

<p>Anti-ganglioside Autoantibodies: Farmers vs. Controls (n = 173)*.</p