RT Book, Section
A1 Ryan, Kenneth J.
SR Print(0)
ID 1185630861
T1 Persistent Viral Infections of the Central Nervous System
T2 Sherris & Ryan's Medical Microbiology, 8th Edition
YR 2022
FD 2022
PB McGraw-Hill Education
PP New York, NY
SN 9781260464283
LK accessmedicine.mhmedical.com/content.aspx?aid=1185630861
RD 2024/04/25
AB OverviewPersistent  viral  infections  are  those  in  which  termination  of  early  symptoms  and  disease  is  not  accompanied  by  elimination  of  the  virus  from  the  host  but  by  the  persistence  of  viral  genome  in  the  host.  Persistent  viral  infections  could  be  latent  infection,  in  which  viral  genome  is  maintained  without  making  any  infectious  virus  particles  or  chronic  infection,  where  a  low  level  of  virus  is  made  without  causing  any  or  little  damage  to  the  target  tissue.  Three  main  conditions  must  be  fulfilled  for  a  virus  to  cause  persistent  infection,  including  little  to  no  cytopathic  effect  of  the  virus  to  the  host  cells,  maintenance  of  viral  genome  in  the  host  cell,  and  avoid  elimination  by  the  immune  system.  Several  viruses  have  utilized  these  strategies  to  persist  in  an  immune-privileged  site,  the  central  nervous  system  (CNS),  and  over  time  after  reactivation  cause  rare  disease  in  the  CNS  or  distant  sites.  These  viruses  include  measles,  rubella,  enterovirus,  HIV,  JCV,  HSV  1,  2,  and  VZV.  In  addition,  nonconventional  agents  such  as  prions  (infectious  prion  proteins,  PrPsc)  cause  slow  degenerative  diseases  of  the  CNS  such  as  Creutzfeldt-Jakob  disease  (CJD)  and  others.  These  persistent  viral  agents  and  prions  and  the  diseases  they  cause  will  be  discussed  in  this  chapter.