Sene Ousseynou, Sagne Samba Niang, Ngom Déthié, Bocoum Mamoudou, Diallo Mamadou Korka, Khoulé Aliou, Faye Elisabeth Thérèse, Diop Sokhna Mayemouna, Diallo Idrissa, Loucoubar Cheikh, Diallo Mawlouth, Dia Ndongo, Sall Yoro, Diop Boly, Ndiaye Mamadou, Sall Amadou Alpha, Weidmann Manfred, Diagne Moussa Moise, Fall Malick, Faye Ousmane, Faye Oumar, Simon-Lorière Etienne, Diallo Diawo, Barry Mamadou Aliou, Fall Gamou
Virology Department, Institut Pasteur de Dakar, Dakar, Senegal.
Epidemiology, Clinical Research and Data Science Department, Institut Pasteur de Dakar, Dakar, Senegal.
Am J Trop Med Hyg. 2025 Jul 8;113(3):555-563. doi: 10.4269/ajtmh.24-0445. Print 2025 Sep 3.
Crimean-Congo hemorrhagic fever (CCHF) is a lethal zoonotic disease transmitted through tick bites and contact with infected animals or humans. As CCHF continues to expand worldwide, we report on the first severe outbreak in Senegal (Podor, Saint-Louis region) in 2022. We conducted a comprehensive outbreak investigation after a confirmed CCHF human case in Podor. This included sample collections from humans, animals, and ticks from the household and surrounding area. Human and animal samples were tested by ELISA for antibodies to CCHF virus and by reverse transcription polymerase chain reaction (RT-PCR) for CCHF virus RNA, whereas tick samples underwent CCHF RT-PCR only. Positive RT-PCR samples underwent viral genome sequencing for genetic characterization. We determined three CCHF human cases, with two deaths, as well as virus circulation in 11 ticks and in livestock, with an overall seroprevalence of 42.5%. CCHF IgG antibodies were detected in human contact cases, showing its prior prevalence in the area. Phylogenetic analyses revealed high genetic diversity within CCHF genotypes, with existence of reassortants and cocirculation of two different isolates from various origins in Mboyo and Nenette villages, where human cases were detected. The data showed a correlation between the strains identified in humans and ticks in each village, showing two independent emergences in Podor. The outbreak in Podor was probably because of the high abundance of animal hosts in this sylvopastoral area, the diversity of tick populations with the presence of the main CCHF vectors, and the increasing prevalence of CCHF virus. The surveillance in this area needs to be strengthened.
克里米亚-刚果出血热（CCHF）是一种致命的人畜共患病，通过蜱虫叮咬以及与受感染的动物或人类接触传播。随着CCHF在全球范围内持续蔓延，我们报告了2022年在塞内加尔（圣路易地区波多尔）发生的首例严重疫情。在波多尔确诊一例CCHF人类病例后，我们开展了全面的疫情调查。这包括从人类、动物以及家庭和周边地区的蜱虫采集样本。人类和动物样本通过酶联免疫吸附测定（ELISA）检测CCHF病毒抗体，通过逆转录聚合酶链反应（RT-PCR）检测CCHF病毒RNA，而蜱虫样本仅进行CCHF RT-PCR检测。RT-PCR阳性样本进行病毒基因组测序以进行基因特征分析。我们确定了3例CCHF人类病例，其中2例死亡，同时在11只蜱虫和家畜中检测到病毒传播，总体血清阳性率为42.5%。在人类接触病例中检测到CCHF IgG抗体，表明该地区此前存在CCHF病毒。系统发育分析显示CCHF基因型内存在高度遗传多样性，在检测到人类病例的姆博约村和内内特村存在重配体以及来自不同来源的两种不同分离株共同传播。数据显示每个村庄人类和蜱虫中鉴定出的毒株之间存在相关性，表明在波多尔出现了两次独立的疫情暴发。波多尔的疫情暴发可能是由于这个农牧交错地区动物宿主数量众多、存在主要CCHF传播媒介且蜱虫种类多样，以及CCHF病毒流行率上升。该地区需要加强监测。
