Infected nervous tissue or salivary gland tissue is the best source of the virus . 感染的神经组织或涎腺组织是病毒的最好来源。
2.
Working with world health organization and centre for disease control and prevention to trace the source of the virus and ascertain the mode of transmission 与世界?生组织及疾病控制及预防中心合作,追查病毒来源及确定传播途径;