Enterovirus 71 Infection

　　肠道病毒71型为耐热、耐酸的微小RNA病毒，对乳鼠有致病力，引起类似柯萨奇A组病毒所引起的肌炎。在恒河猴中经口或注射感染能产生类似脊髓灰质炎的疾病。在猴子中的神经毒力似与该病毒在高温中的复制能力有关，但寡核苷酸电泳和凝胶电泳分离病毒蛋白后却未能区分无神经毒力株。

　　肠道病毒71型感染可出现各个系统的并发症，例如出现流行性肌痛疱疹性咽峡炎婴儿急性心肌炎无菌性脑膜炎，急性流行性眼结膜炎等并发症并由此进入血循环导致病毒血症(第一次病毒血症)，病毒可随血流带至全身各器官如中枢神经系统皮肤粘膜心脏，呼吸器官肝胰肌肉等处在该处进一步繁殖，引起病变并再次进入血环引起病毒血症。

　　肠道病毒71型可引起多种临床表现，在澳大利亚，瑞典和日本，主要表现为手，足，口腔病，通常发生于1～3天的前驱性发热之后，未观察到严重的中枢神经系统疾病，而1975年在保加利亚发生的肠道病毒71型流行中，则以无菌性脑膜炎为主，21％病例表现为类似于脊髓灰质炎的急性瘫痪，病情发展迅速，起病后10～30h即出现瘫痪，约半数病例表现为脑炎或脑神经损害(延髓性麻痹)，确诊病例的总病死率为6.2％，其中29.5％为瘫痪性疾病，65％为延髓性麻痹。

　　在美国的罗彻斯特，纽约和日本，香港发生的小规模流行暴发中均观察到手，足，口腔病与严重中枢神经系统感染可发生于肠道病毒71型的同一次流行之中。

　　其他较少见的临床表现包括：全身性斑丘疹，心肌炎，传染性多神经炎和上呼吸道炎，曾有1例新生儿疾病具有肠道病毒71型的血清学证据的报道。

　　肠道病毒71型感染的预防主要是日常生活中，要养成良好的习惯，注意卫生，杜绝传染源。教育孩童、学生自幼养成卫生习惯，改掉吮手指的习惯，远离垃圾及不洁环境;养成游戏后、饭前、便后一定彻底洗手的习惯。大人感染后没有症状，成为隐性传染源，更危险。因为此病毒一般来说并不没特殊的治疗药物，而且还会并发其它症状。特别是肠病毒流行高峰期(6～9月)，家长更要多多注意，防治肠病毒必须由个人卫生及环境卫生着手，除了要养成良好的生活习惯，经常正确洗手，注意饮食及饮水必须煮熟及煮沸。其他的预防办法如下：

　　1. Ensure that the health conditions of public places meet the requirements

　　The environment of nurseries and kindergartens, toys, public swimming pools, and other public places must be strictly disinfected.

　　2. Prevent the virus from spreading through the mouth

　　Both children and adults can be infected because this virus is transmitted through close contact with saliva, vesicular fluid, contaminated food and items from feces.

　　3. Isolate patients

　　When symptoms of this disease are found, such as finding children with hand, foot, and mouth signs, they should be isolated from other children, and utensils, toys, and other items should be separated, and they should be sent to the hospital for isolation treatment immediately.

　　4. Improve the reporting system of the epidemic situation

　　For children with fever, cold, or respiratory symptoms, or those found to have hand, foot, and mouth sores, they should go to the hospital for treatment as soon as possible.

　　5. Improve human immunity and resist viruses

　　Improving human immunity and taking preventive measures are equally important, as this is a fundamental measure. Eat more fruits in daily life.

　　EV71 can be isolated from a variety of clinical specimens, including vesicular fluid, feces, oropharyngeal secretions, urine, and cerebrospinal fluid, with the highest isolation rate from vesicular fluid and the lowest from cerebrospinal fluid. The isolation and culture positivity rate is highest in African green monkey kidney cells and rat embryos, although cytopathic changes can only be observed from the 5th to 8th day under the most suitable conditions. Serological specific antibody detection is helpful for diagnosis.

　　Severe brain nerve damage patients may have abnormal electroencephalograms.

　　Patients with EV71 infection have no special dietary restrictions, mainly paying attention to food hygiene, washing hands before meals. The patient's diet should be light and easy to digest, eat more vegetables and fruits, reasonably match the diet, and pay attention to adequate nutrition. In addition, patients should also pay attention to avoiding spicy, greasy, and cold foods.

　　There is currently a lack of specific and effective antiviral drugs for EV71 infection, and clinical treatment mainly focuses on symptomatic and supportive therapy. The vast majority of patients are mild, with a natural course of about 1 week, good prognosis, and only symptomatic treatment is needed. However, for severe patients, early identification and active treatment are required.