Table 2.

Preliminary evaluation of sensitivity, specificity, positive and negative predicted values for the Nb44/Nb42 LFA performed on plasma samples from experimentally infected cattle.

	Cattle sera infected with
	T. congolense	Naive	T. vivax
Positive	19	1	2
Negative	5	14	20
Total	24	15	22
Sensitivity ± 95% CI (%)	79.17 (19/24) ± 16.25
Specificity ± 95% CI (%)	91.89 (34/37) ± 8.80
PPV ± 95% CI (%)	86.36 (19/22) ± 14.34
NPV ± 95% CI (%)	87.18 (34/39) ± 10.47

The samples were obtained from a stored GALVmed plasma sample collection at Clinvet, South Africa. The collection contains plasma samples of Holstein cows that were experimentally infected with T. vivax STIB 719 or T. congolense KONT 2/133. Because these animals were involved in drug development programs, they were treated as soon mild disease symptoms developed combined with an observed hematocrit value lower than 25%.