title: Electron Microscopy of Alkhumra Hemorrhagic Fever Virus.
abstract: Alkhumra hemorrhagic fever virus (AHFV) is a newly described zoonotic flavivirus that was first isolated during 1994-1995 from the Alkhumra district south of Jeddah, Saudi Arabia. Subsequently, the virus was also isolated from Makkah city (2001-2003) and Najran (2008-2009), Saudi Arabia. The virus causes acute febrile illness with hepatitis, hemorrhagic manifestations, and encephalitis. A case fatality rate of 25% was reported among hospitalized patients. Although several biological and molecular characteristics of the virus have been published, no data are available on electron microscopic features of the virus. In this article, we describe the morphological features and metrics of the AHFV particles under electron microscopy, and localization of the virus particles in brain cells of newborn Wistar rats and in Rhesus monkey (Macaca mulatta) kidney epithelial cells (LLC-MK2). Virus particles in both the LLC-MK2 cells and the rat brain cells showed dark hexagonal core (capsid) and a translucent envelope. The mean diameter of the enveloped virus particle was 40.59 ± 1.29 nm in the rat brain cells (n = 154) and 40.97 ± 1.40 nm in the LLC-MK2 cells (n = 105; p > 0.05). The virus particles, both in vitro and in vivo, were enclosed into cytoplasmic vesicles. In conclusion, the shape, size, and diameter of the AHFV particle lie within the framework of the genus Flavivirus, family Flaviviridae.
authors.affiliation: 1 Department of Medicine, Faculty of Medicine, King Abdulaziz University , Jeddah, Saudi Arabia .|2 The Scientific Chair of Sheikh Mohammad Hussein Al-Amoudi for Viral Hemorrhagic Fever, King Abdulaziz University , Jeddah, Saudi Arabia .
authors.forename: Tariq A
authors.initials: TA
authors.lastname: Madani
authors.affiliation: 2 The Scientific Chair of Sheikh Mohammad Hussein Al-Amoudi for Viral Hemorrhagic Fever, King Abdulaziz University , Jeddah, Saudi Arabia .|3 Special Infectious Agents Unit, King Fahd Medical Research Center, King Abdulaziz University , Jeddah, Saudi Arabia .
authors.forename: El-Tayb M E
authors.initials: EM
authors.lastname: Abuelzein
authors.affiliation: 4 Department of Pathology, Faculty of Medicine, King Abdulaziz University , Jeddah, Saudi Arabia .
authors.forename: Sawsan M
authors.initials: SM
authors.lastname: Jalalah
authors.affiliation: 2 The Scientific Chair of Sheikh Mohammad Hussein Al-Amoudi for Viral Hemorrhagic Fever, King Abdulaziz University , Jeddah, Saudi Arabia .|5 Laboratory Animals Unit, King Fahd Medical Research Center, King Abdulaziz University , Jeddah, Saudi Arabia .
authors.forename: Huda
authors.initials: H
authors.lastname: Abu-Araki
authors.affiliation: 2 The Scientific Chair of Sheikh Mohammad Hussein Al-Amoudi for Viral Hemorrhagic Fever, King Abdulaziz University , Jeddah, Saudi Arabia .|3 Special Infectious Agents Unit, King Fahd Medical Research Center, King Abdulaziz University , Jeddah, Saudi Arabia .|6 Department of Medical Laboratory Technology, Faculty of Applied Medical Science, King Abdulaziz University , Jeddah, Saudi Arabia .
authors.forename: Esam I
authors.initials: EI
authors.lastname: Azhar
authors.affiliation: 2 The Scientific Chair of Sheikh Mohammad Hussein Al-Amoudi for Viral Hemorrhagic Fever, King Abdulaziz University , Jeddah, Saudi Arabia .|3 Special Infectious Agents Unit, King Fahd Medical Research Center, King Abdulaziz University , Jeddah, Saudi Arabia .
authors.forename: Ahmed M
authors.initials: AM
authors.lastname: Hassan
authors.affiliation: 2 The Scientific Chair of Sheikh Mohammad Hussein Al-Amoudi for Viral Hemorrhagic Fever, King Abdulaziz University , Jeddah, Saudi Arabia .|7 Department of Family and Community Medicine, Faculty of Medicine, King Abdulaziz University , Jeddah, Saudi Arabia .
authors.forename: Hussein M S
authors.initials: HM
authors.lastname: Al-Bar
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D001921:Brain / Q000166:cytology / Q000821:virology; D002460:Cell Line; D004669:Encephalitis Viruses, Tick-Borne / Q000502:physiology / Q000648:ultrastructure*; D008253:Macaca mulatta; D051381:Rats; D017208:Rats, Wistar
keywords: Alkhumra hemorrhagic fever virus; LLC-MK2; Wistar rats; electron microscopy; flavivirus; virus diameter