TABLE 1.

Immunohistochemistry assay results for third eyelid lymphoid tissue from sheep with clinical signs suggestive of scrapie^a and from sheep with no reported exposure to scrapie

Scrapie agent status	No. of sheep	No. of sheep with the following result by IHC of third eyelid lymphoid tissueb
		Positive	Negative
Infectedc	42	41	1
Uninfectedd	7	1	6
No exposure to scrapiee	48	0	48

^aClinical signs included wool rubbing, weight loss, and/or ataxia. 

^bResults of immunohistochemistry (IHC) assay performed with MAb F89/160.1.5. 

^cPrP-Sc immunostaining of the medulla oblongata at the level of the obex (U.S. samples, n = 28) or routine histopathology of brain (samples from the United Kingdom; n = 14) was found for sheep with scrapie. 

^dNo lesions characteristic of scrapie (samples from the United Kingdom, n = 5 with a negative eyelid immunostaining result and n = 1 with a positive eyelid immunostaining result) or the lack of detection of PrP-Sc in brain, tonsil, retropharyngeal lymph node, or submandibular lymph node (U.S. samples; n = 1) was found for sheep without scrapie. 

^eSheep from three flocks with no reported exposure to scrapie for the last 5 years.