After they had been raised separa-tely for six months, the negative monkeys for B virus related antibodywere detected in IEA, 98.3% of them were still negative for B virusrelated antibody.

• 用IFA检查了B病毒相关抗体阴性的恒河猴，在单笼隔离饲养六个月后，有98.；3%25的动物B病毒相关抗体仍为阴性，表明IRA的阴性结果有较好的一致性。