Table 2.

Interpretation algorithm for HEV-A4 p239 and HEV-C1 p241 IgG enzymatic immunoassays.

Serum/plasma sample run in parallel in HEV-A4 p239 and HEV-C1 p241 IgG EIAs
HEV-A4 p239 EIA result (positive if OD ≥0.437)	HEV-C1 p241 EIA result (positive if OD ≥0.864)	Interpretation
Negative	Negative	Seronegative for hepatitis E
Positive	Negative	Exposure to HEV-A
Negative	Positive	Exposure to HEV-C1
Positive	Positive	Assess A/C ratio∗: If ≥2.947, consistent with exposure to HEV-A. Additional HEV-C1 exposure possible. If <2.947, consistent with exposure to HEV-C1. Additional HEV-A exposure possible.

EIA, enzymatic immunoassay; HEV-A, Paslahepevirus balayani; HEV-C1, Rocahepevirus ratti; OD, optical density.

^∗A/C ratio = OD_{HEV-A4 p239}/OD_{HEV-C1 p241}.