Grace John-Ugwuanya A, Egoh Ifunanya J, Udensi Nnenna
Medbury Medical Services, Lagos, Nigeria.
Department of Virology, University of Ibadan, Ibadan, Nigeria.
Ther Adv Infect Dis. 2021 Nov 29;8:20499361211058252. doi: 10.1177/20499361211058252. eCollection 2021 Jan-Dec.
Lassa fever is a viral haemorrhagic fever with non-specific symptoms that has shown an upward trend in Nigeria and other West African countries, which is depicted by high incidence and case fatality in recent years. There are different reports on the yearly case burden of Lassa fever from the Federal Ministry of Health in Nigeria, through the regulatory body - Nigeria Centre for Disease Control (NCDC). Being the epicentre of the disease, Lassa fever has been exported from Nigeria to both neighbouring and distant countries.Methods: The aim of this review was to carry out a retrospective analysis from January 2015 to 26 September 2021 of the weekly and yearly outbreak of Lassa fever in Nigeria based on selected publications. The focus was on timely diagnosis, treatment option, public health interventions and progress of clinical trials for vaccine candidates, and to identify proactive measures that can be sustained to curb periodic outbreaks. The review was done using percentages, cross-tabulation and graphical charts.
The predominant age group infected was 21 to 40 years with a male to female ratio of 1:0.8. A total of 3311 laboratory-confirmed Lassa fever cases out of 20,588 suspected cases were identified from 29 states. Edo, Ondo, Taraba, Ebonyi, Bauchi, Plateau and Nasarawa had yearly Lassa fever incidence over the time frame considered. Contact tracing was done on over 33,804 individuals with about 90% completing follow-up. Case fatality rate within the period ranged from 9.3% to 29.2%. There is a sharp decline in the epidemiological trend of Lassa fever in the yearly seasonal peaks from weeks 1 to 13 with about 75% reduction in incidence between 2020 and 2021.
The effective management of Lassa fever needs the implementation of preventive methods, prompt laboratory diagnosis, timely treatment, provision of personal protective equipment, cross-border surveillance, contact tracing, community awareness and vector control in order to minimise spread.
拉沙热是一种具有非特异性症状的病毒性出血热，在尼日利亚和其他西非国家呈上升趋势，近年来发病率和病死率都很高。尼日利亚联邦卫生部通过监管机构——尼日利亚疾病控制中心（NCDC）发布了关于拉沙热年度病例负担的不同报告。作为该疾病的中心，拉沙热已从尼日利亚传播到邻国和遥远的国家。
本综述的目的是根据选定的出版物，对2015年1月至2021年9月26日尼日利亚拉沙热的每周和年度疫情进行回顾性分析。重点是及时诊断、治疗选择、公共卫生干预措施以及候选疫苗临床试验的进展，并确定可维持的积极措施以遏制周期性疫情。该综述采用百分比、交叉表和图表进行。
感染的主要年龄组为21至40岁，男女比例为1:0.8。从29个州的20588例疑似病例中，共确诊3311例实验室确诊的拉沙热病例。江户州、翁多州、塔拉巴州、埃邦伊州、包奇州、高原州和纳萨拉瓦州在考虑的时间段内有拉沙热年度发病率。对超过33804人进行了接触者追踪，约90%完成了随访。该期间的病死率在9.3%至29.2%之间。在第1周至第13周的年度季节性高峰中，拉沙热的流行病学趋势急剧下降，2020年至2021年发病率降低了约75%。
拉沙热的有效管理需要实施预防方法、及时的实验室诊断、及时治疗、提供个人防护设备、跨境监测、接触者追踪、社区意识和病媒控制，以尽量减少传播。
