Hepatitis E virus (HEV) infections are a major cause of acute viral hepatitis in humans worldwide. In immunocompetent individuals, the majority of HEV infections remain asymptomatic and lead to spontaneous clearance of the virus, and only a minority of individuals with infection (5–16%) experience symptoms of acute viral hepatitis. However, HEV infections can cause up to 30% mortality in pregnant women, become chronic in immunocompromised patients and cause extrahepatic manifestations. A growing body of evidence suggests that the host immune response to infection with different HEV genotypes is a critical determinant of distinct HEV infection outcomes. In this Review, we summarize key components of the innate and adaptive immune responses to HEV, including the underlying immunological mechanisms of HEV associated with acute and chronic liver failure and interactions between T cell and B cell responses. In addition, we discuss the current status of vaccines against HEV and raise outstanding questions regarding the immune responses induced by HEV and treatment of the disease, highlighting areas for future investigation.

戊型肝炎病毒 (HEV) 感染是全世界人类急性病毒性肝炎的主要原因。在免疫功能正常的个体中，大多数 HEV 感染仍然无症状，并导致病毒自发清除，只有少数感染者 (5-16%) 出现急性病毒性肝炎的症状。然而，HEV 感染可导致孕妇死亡率高达 30%，在免疫功能低下的患者中转为慢性感染，并引起肝外表现。越来越多的证据表明，宿主对不同 HEV 基因型感染的免疫反应是不同 HEV 感染结果的关键决定因素。在这篇综述中，我们总结了针对 HEV 的先天性和适应性免疫反应的关键组成部分，包括与急性和慢性肝衰竭相关的 HEV 潜在免疫机制以及 T 细胞和 B 细胞反应之间的相互作用。此外，我们还讨论了 HEV 疫苗的现状，并提出了有关 HEV 诱导的免疫反应和疾病治疗的突出问题，强调了未来研究的领域。