Dwalu Emmanuel, Tweya Hannock, Beglaryan Mher, Umeokonkwo Chukwuma D, Jetoh Ralph W, Shobayo Bode I, Tarweh Fahn, Owiti Philip, Relan Pryanka, Hassan Shermarke, Goteh George W, Lehyen Darius B, Ako-Egbe Louis, Kamara Ibrahim Franklyn, Akpan Godwin E, Adewuyi Peter, Kpanyen Patrick N, Vonhm Benjamin T, Gilayeneh Julius S M
National Public Health Institute of Liberia, Monrovia, Liberia.
International Training and Education Center for Health (I-TECH), Lilongwe, Malawi.
F1000Res. 2025 May 15;13:661. doi: 10.12688/f1000research.150743.2. eCollection 2024.
Lassa fever (LF) is an endemic and immediately notifiable disease in Liberia, and one laboratory confirmed case constitutes an outbreak. We described the epidemiological characteristics and hospital outcomes of LF cases hospitalized during the 2022-2023 outbreak in Liberia.
A retrospective cohort study was conducted using routine LF surveillance data from the 2022-2023 outbreak in Liberia. Descriptive statistics were used to summarize the data and log binomial regression to assess the association between epidemiological characteristics and mortality.
A total of 439 suspected LF cases were reported. The median age was 22 (interquartile range (IQR): 10-33) years and 233 (53%) were females. The median number of days between symptom onset and admission was 4 (IQR 2-7). Of the 439 cases, 416 (95%) were tested for LF and 138 were confirmed with 33% positivity rate. The majority, 95 (69%), of confirmed cases were <30 years, 78 (57%) were females, and 81 (59%) were reported during the dry season (October - March). Contact with rodents, 95 (69%), was the commonest mode of exposure. Fever, 128 (93%), malaise, 121 (88%), headache, 114 (83%) and myalgia, 114 (83%) were the most common clinical characteristics. There were 83 (19%) deaths among hospitalized suspected LF cases - 42 deaths (15%) among 278 individuals who tested negative and 41 among confirmed cases with 30% case fatality rate (CFR). Age 40-49 years accounted for 8/12 (67%) and those aged≥50 reported 5/8 (63%) of the deaths among the confirmed cases. There was no significant association between epidemiological characteristics and LF mortality.
The outbreak highlighted a high disease burden of LF with young adults disproportionately infected, and mortality, even among those who tested negative for the virus. This underscores the urgent need for preventive measures like vaccines and health education campaigns.
拉沙热（LF）是利比里亚的一种地方性且需立即上报的疾病，一例实验室确诊病例即构成一次疫情爆发。我们描述了2022 - 2023年利比里亚疫情爆发期间住院的拉沙热病例的流行病学特征及医院治疗结果。
利用利比里亚2022 - 2023年疫情爆发期间的常规拉沙热监测数据进行了一项回顾性队列研究。采用描述性统计来汇总数据，并使用对数二项回归评估流行病学特征与死亡率之间的关联。
共报告了439例疑似拉沙热病例。中位年龄为22岁（四分位间距（IQR）：10 - 33岁），233例（53%）为女性。症状出现至入院的中位天数为4天（IQR 2 - 7天）。在439例病例中，416例（95%）接受了拉沙热检测，138例确诊，阳性率为33%。确诊病例中，大多数95例（69%）年龄小于30岁，78例（57%）为女性，81例（59%）报告于旱季（10月至3月）。接触啮齿动物是最常见的暴露方式，有95例（69%）。发热128例（93%）、不适121例（88%）、头痛114例（83%）和肌痛114例（83%）是最常见的临床特征。住院的疑似拉沙热病例中有83例（19%）死亡——278例检测阴性者中有42例死亡（15%），确诊病例中有41例死亡，病死率（CFR）为30%。40 - 49岁年龄组占确诊病例死亡数的8/12（67%），≥50岁者占确诊病例死亡数的5/8（63%）。流行病学特征与拉沙热死亡率之间无显著关联。
此次疫情突出了拉沙热的高疾病负担，年轻人感染比例过高，且即使是病毒检测阴性者也有死亡情况。这凸显了迫切需要采取如疫苗和健康教育活动等预防措施。
