Abstract
Grass carp reovirus(GCRV)causes extensive infection and death in grass carp and black carp fingerlings,with a highly seasonal prevalence.Previous studies suggested that GCRV can become latent after primary infection.In this study,we investigated type Ⅱ GCRV(GCRV-Ⅱ)latency in asymptomatic grass carp with GCRV infection or exposure history.We found that during latent infection,GCRV-Ⅱ was detectable only in the brain of grass carp,unlike the multi-tissue distribution observed in natural infection.GCRV-Ⅱ only caused damage to the brain during latent infection,while in natural infection,brain,heart,and eye tissues had relatively higher viral loads.We also discovered viral inclusion bodies in infected fish brains.Additionally,GCRV-Ⅱ distribution in grass carp was notably affected by ambient temperature,with the virus targeting the brain only during low temperatures and multi-tissue distribution during high temperatures.This study provides insights into the mechanisms of GCRV-Ⅱlatent infection and reactivation and contributes to the prevention and control of GCRV pandemics.
基金项目
National Natural Science Foundation of China(31930114)
NETL
NSTL
万方数据