Sama Daniel Juma, Haider Najmul, Guitian Javier, Osman Abdinasir Yusuf, Ntoumi Francine, Zumla Alimuddin, Kock Richard, Ansumana Rashid
School of Public Health, Njala University, Bo City, Sierra Leone.
Department of Pathobiology and Population Sciences, The Royal Veterinary College, Hatfield, Hertfordshire, AL9 7TA, UK.
Epidemiol Infect. 2024 Nov 20;152:e177. doi: 10.1017/S095026882400164X.
Lassa fever (LF) virus (LASV) is endemic in Sierra Leone (SL) and poses a significant public health threat to the region; however, no risk factors for clinical LF have been reported in SL. The objective of this study was to identify the risk factors for clinical LF in an endemic community in SL. We conducted a case-control study by enrolling 37 laboratory-confirmed LF cases identified through the national LF surveillance system in SL and 140 controls resided within a one-kilometre radius of the case household. We performed a conditional multiple logistic regression analysis to identify the risk factors for clinical LF. Of the 37 cases enrolled, 23 died (62% case fatality rate). Cases were younger than controls (19.5 years vs 28.9 years, < 0.05) and more frequently female (64.8% vs 52.8%). Compared to the controls, clinical LF cases had higher contact with rodents (rats or mice) in their households in the preceding three weeks (83.8% vs 47.8%). Households with a cat reported a lower presence of rodents (73% vs 38%, < 0.01) and contributed to a lower rate of clinical LF (48.6% vs 55.7%) although not statistically significant ( = 0.56). The presence of rodents in the households (matched adjusted odds ratio (mAOR): 11.1) and younger age (mAOR: 0.99) were independently associated with clinical LF.Rodent access to households and younger age were independently associated with clinical LF. Rodent access to households is likely a key risk factor for clinical LF in rural SL and potentially in other countries within the West African region. Implementing measures to control rodents and their access to households could potentially decrease the number of clinical LF cases in rural SL and West Africa.
拉沙热（LF）病毒（LASV）在塞拉利昂（SL）呈地方性流行，对该地区构成重大公共卫生威胁；然而，在塞拉利昂尚未有临床拉沙热的风险因素报道。本研究的目的是确定塞拉利昂一个地方性流行社区中临床拉沙热的风险因素。我们进行了一项病例对照研究，纳入了通过塞拉利昂国家拉沙热监测系统确定的37例实验室确诊的拉沙热病例，以及居住在病例家庭半径一公里范围内的140名对照。我们进行了条件多因素逻辑回归分析以确定临床拉沙热的风险因素。在纳入的37例病例中，23例死亡（病死率62%）。病例比对照更年轻（19.5岁对28.9岁，<0.05），女性比例更高（64.8%对52.8%）。与对照相比，临床拉沙热病例在前三周内与其家庭中的啮齿动物（大鼠或小鼠）接触更频繁（83.8%对47.8%）。有猫的家庭报告啮齿动物的存在较少（73%对38%，<0.01），且临床拉沙热发病率较低（48.6%对55.7%），尽管差异无统计学意义（=0.56）。家庭中存在啮齿动物（匹配调整优势比（mAOR）：11.1）和年龄较小（mAOR：0.99）与临床拉沙热独立相关。啮齿动物进入家庭和年龄较小与临床拉沙热独立相关。在塞拉利昂农村地区以及西非其他国家，啮齿动物进入家庭可能是临床拉沙热的一个关键风险因素。实施控制啮齿动物及其进入家庭的措施可能会减少塞拉利昂农村地区和西非临床拉沙热病例的数量。
