Safronetz David, Rosenke Kyle, Meade-White Kimberley, Sloan Angela, Maiga Ousmane, Bane Sidy, Martellaro Cynthia, Scott Dana P, Sogoba Nafomon, Feldmann Heinz
Special Pathogens, National Microbiology Laboratory Branch, Public Health Agency of Canada, Winnipeg, Manitoba, Canada.
Laboratory of Virology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, national Institutes of Health, Rocky Mountain Laboratories, Hamilton, MT, USA.
PNAS Nexus. 2022 Jul 13;1(3):pgac114. doi: 10.1093/pnasnexus/pgac114. eCollection 2022 Jul.
Little is known about the temporal patterns of infection and transmission of Lassa virus (LASV) within its natural reservoir (). Here, we characterize infection dynamics and transmissibility of a LASV isolate (Soromba-R) in adult lab-reared originating from Mali. The lab-reared M. proved to be highly susceptible to LASV isolates from geographically distinct regions of West Africa via multiple routes of exposure, with 50% infectious doses of < 1 TCID. Postinoculation, LASV Soromba-R established a systemic infection with no signs of clinical disease. Viral RNA was detected in all nine tissues examined with peak concentrations detected between days 7 and 14 postinfection within most organs. There was an overall trend toward clearance of virus within 40 days of infection in most organs. The exception is lung specimens, which retained positivity throughout the course of the 85-day study. Direct (contact) and indirect (fomite) transmission experiments demonstrated 40% of experimentally infected were capable of transmitting LASV to naïve animals, with peak transmissibility occurring between 28 and 42 days post-inoculation. No differences in patterns of infection or transmission were noted between male and female experimentally infected rodents. Adult lab-reared are highly susceptible to genetically distinct LASV strains developing a temporary asymptomatic infection associated with virus shedding resulting in contact and fomite transmission within a cohort.
关于拉沙病毒（LASV）在其自然宿主内的感染和传播时间模式，人们了解甚少。在此，我们描述了一种源自马里的成年实验室饲养的LASV分离株（Soromba - R）的感染动态和传播能力。实验室饲养的该物种经多种暴露途径被证明对来自西非地理上不同区域的LASV分离株高度易感，50%感染剂量<1个组织培养感染剂量（TCID）。接种后，LASV Soromba - R建立了全身性感染且无临床疾病迹象。在所检测的所有九个组织中均检测到病毒RNA，大多数器官在感染后第7天至14天之间检测到峰值浓度。在大多数器官中，总体趋势是在感染后40天内病毒清除。例外的是肺标本，在为期85天的研究过程中一直保持阳性。直接（接触）和间接（污染物）传播实验表明，40%的实验感染该物种能够将LASV传播给未感染的动物，接种后第28天至42天之间传播能力达到峰值。在实验感染的啮齿动物中，未观察到雄性和雌性在感染或传播模式上的差异。成年实验室饲养的该物种对遗传上不同的LASV毒株高度易感，会发展出与病毒脱落相关的暂时性无症状感染，从而在群体内导致接触和污染物传播。
