拉沙热

定义

一种在撒哈拉以南西非某些地区呈地方性流行的疾病，由拉沙病毒（Lassa virus）感染所致。多数感染者症状轻微或无症状，但亦可引发重症甚至死亡。 当出现症状时，疾病通常呈渐进性起病，初期表现为发热、全身乏力、头痛及不适感。数日后，可相继出现咽痛、肌肉疼痛、胸痛、恶心、呕吐、腹泻、咳嗽及腹痛等症状。随着病情进展，重症患者可能出现面部肿胀、胸腔积液、口腔、鼻腔、阴道或胃肠道出血以及低血压。疾病晚期可出现休克、抽搐、震颤、定向障碍及昏迷。住院患者中，约15%死于拉沙热；在死亡病例中，患者通常于症状出现后14天内死亡。 妊娠期间，拉沙热可导致孕产妇及胎儿死亡率显著升高，尤其在妊娠晚期更为严重。在妊娠第三期，胎儿死亡率和孕产妇死亡率分别可超过80%和30%。 部分患者康复期延长，有时可遗留后遗症。突发性听力丧失已有报道，发生率不一，高达25%的康复患者在急性病程中或康复后出现该症状；多数情况下，听力丧失被报道为永久性。其他较少见的后遗症还包括神经系统症状、视力障碍、关节疼痛、暂时性脱发以及心理障碍等。 拉沙热的潜伏期为2–21天。 传播途径包括接触被感染的多乳鼠的尿液或粪便污染的食物或家庭用品，或直接接触感染的多乳鼠。 虽然程度要轻得多，但拉沙病毒也可通过直接接触拉沙热患者的血液、尿液、粪便或其他体液而在人与人之间传播。人际传播主要发生在医疗机构中，此时病毒还可能通过被污染的医疗器械（如重复使用的针头）传播。 诊断方法是通过分子生物学或血清学检测，在患者血液样本中检出拉沙病毒。

A disease endemic in some areas of sub-Saharan Western Africa caused by infection with Lassa virus. Infection is mild or asymptomatic in most cases but can cause severe illness or death. When it is symptomatic, the onset of the disease is usually gradual, starting with fever, general weakness headache and malaise. After a few days, sore throat, muscle pain, chest pain, nausea, vomiting, diarrhoea, cough and abdominal pain may follow. As the disease progresses, in severe cases facial swelling, fluid in the lung cavity, bleeding from the mouth, nose, vagina or gastrointestinal tract and low blood pressure may develop. Shock, seizures, tremor, disorientation, and coma may be seen in the later stages. Among hospitalized patients, approximately 15% die of Lassa fever disease. In fatal cases, death usually occurs within 14 days of symptom onset. During pregnancy, Lassa fever can cause high maternal and foetal mortality, especially late in pregnancy. In the third trimester, fetal death and maternal death rates can exceed 80% and 30% respectively. Prolonged convalescence in some patients has been documented leading sometimes to sequelae. Sudden hearing loss has been reported with varying incidence and up to 25% of recovered patients, both during acute disease and after recovery. In most circumstances hearing loss is reported to be permanent. Other sequelae including neurological signs, visual impairment, joint pain, transient hair loss and psychological disorders have been reported to a lesser extent. The incubation period of Lassa fever ranges from 2–21 days. Transmission occurs either through exposure to food or household items that are contaminated with urine or faeces of infected Mastomys rat, or directly via contact with infected rats. Although to a much less extent, Lassa virus may also spread between humans through direct contact with blood, urine, faeces or other bodily secretions of a person infected with Lassa fever. Person-to-person transmission may occur primarily in health-care settings, where the virus may also be spread by contaminated medical equipment, such as re-used needles. Diagnosis occurs by identification of Lassa virus in blood samples by molecular or serologic methods.

索引词 可用于检索该条目的同义词与别名

• 拉沙热
• LF[拉沙热]
• 拉沙病毒引起的脑膜炎
• 拉沙病毒引起的脑炎