复旦大学：《医学微生物学 Medical Microbiology（MBBS）》课程讲义_理论课_Lecture16-Virus Pathogenesis & Antiviral Defenses

Virus Pathogenesis Antiviral Defenses Youhua xie(谢幼华) MOH&MOE Key Lab of Medical Molecular Virology Shanghai Medical College, Fudan University 复旦大学上海医学院 分子病毒学教育部/卫生部重点实验室 yhxie@fudan.edu.cn

Virus Pathogenesis & Antiviral Defenses Virus Pathogenesis & Antiviral Defenses Youhua Xie Youhua Xie (谢幼华 ) MOH&MOE Key Lab of Medical Molecular Virology Sh h i M di l C ll F d U i it Shang h ai M edical C ollege, F u dan U niversit y 复旦大学上海医学院 分子病毒学教育部 /卫生部重点实验室 yhxie@fudan.edu.cn

Only A Few Human Viruses Are Pathogenic o Many viruses on the earth do not infect humans Infections with most of human viruses take place and proceed unnoticed, producing no diseases Non-pathogenic Controlled by human antiviral defenses

Only A Few Human Viruses Are Pathogenic z Many viruses Many viruses on the earth do on the earth do not infect not infect humans z Infections with most of human viruses take place and proceed unnoticed, p g roducin g no diseases ¾ Non-pathogenic ¾ Controlled by human antiviral defenses Controlled by human antiviral defenses

Viral Pathogenesis The process of producing diseases by viral infections The factors that determine the development of viral disease in the host involve complex and dynamic interactions between the virus and the susceptible host o Disease severities are varied, ranging from very mild to fatal depending on the role of both viral and host factors in influencing viral infection and disease progression

Viral Pathogenesis z The process of di pro ucing diseases by vi l i f ti iral infections z The factors that determine the development of viral disease in the host involve complex and dynamic interactions between the host involve complex and dynamic interactions between the virus and the susceptible host z Disease severities are varied ranging from very mild Disease severities are varied, ranging from very mild to fatal, depending on the role of both viral and host factors in influencing viral infection and disease progression

Viral Epidemiology Study the distribution of determinants of disease in human populations Endemic (infections present at fairly low but constant level) Epidemic(infections occur greater than usually found in the population) e Pandemic(infections are spread worldwide)

Viral Epidemiology z Study the distribution istribution of determinants rminants of disease in human populations z Endemic (infections present at fairly low but constant level) z Epidemic (infections occur greater than usually found in the population) z Pandemic (infections are spread worldwide)

Viral Pathogenesis iral pathogenesis can be divided into several stages aspects Transmission and entry of the virus into the host Spread in the host (systemic or localized infections) Tropism Virulence Patterns of viral infection and disease Host factors host defense

Viral Pathogenesis z Viral pathogenesis can be divided into several stages & aspects ¾ Transmission and entry of the virus into the host ¾ Sp (y ) read in the host (systemic or localized infections) ¾ Tropism ¾ Virulence ¾ Patterns of viral infection and disease ¾ Host factors & host defense

Viral Pathogenesis 2 Virus ingested Bood ut asso iaid lymphoid tissue virus invades (va M cells?) endothelium Spinal cord (monocytes wYUS BxCUU Stages of Poliovirus Pathogenesis inc. Al rihts reserved

Viral Pathogenesis St f P li i P th i Stages o f P oliovirus P athogenes is

Common Routes of Human Pathogenic Viral Transmissions ROUTE OF SOURCE/ MODE OF EXAMPLES/VIRUSES ENTRY TRANSMISSION Respiratory Aerosol droplet inhalation Influenza virus, parainfluenza virus, respiratory syncytial virus, measles, mumps, rubella varicella-zoster virus. hantavirus Nose or mouth hand or object nose Common cold(rhinovirus, coronaviru adenovirus) Salivary Direct salivary transfer(eg, kissing) Herpes simplex virus(oral-labial herpes), Epstein-Barr virus(infectious mononucleosis) cytomegalovirus Gastrointestinal Stool hand mouth and/or stool Enteroviruses, hepatitis A virus, poliovirus, Skin Skin discharge air respiratory tract varicella-zoster virus, small pox virus Skin to skin Human papilloma virus(warts) Animal bite to skin Rabies virus Blood Blood products, transfusion or lepatitis B virus, hepatitis C virus, hepatitis D needle prick virus, human immunodeficiency virus(HIV) human T lymphotropic virus, cytomegalovirus

Common Routes of Human Pathogenic Viral Transmissions ROUTE OF ENTRY SOURCE/ MODE OF TRANSMISSION EXAMPLES/VIRUSES Respiratory Aerosol droplet inhalation Influenza virus, parainfluenza virus, respiratory syncytial virus, measles, mumps, rubella, vari ll ce a-zost i hti ter virus, hantavirus Nose or mouth hand or object nose Common cold (rhinovirus, coronavirus, adenovirus) Salivary Direct salivary transfer (eg kissing) Direct salivary transfer (eg, kissing) Herpes simplex virus (oral Herpes simplex virus (oral-labial herpes) labial herpes), Epstein-Barr virus (infectious mononucleosis), cytomegalovirus Gastrointestinal Stool hand mouth and/or stool Enteroviruses, he patitis A virus, poliovirus, object mouth , p ,p , rotavirus Skin Skin discharge air respiratory tract Varicella-zoster virus, small pox virus Skin to skin Skin to skin Human papilloma virus (warts) Human papilloma virus (warts) Animal bite to skin Rabies virus Blood Blood products, transfusion or Hepatitis B virus, hepatitis C virus, hepatitis D needle prick virus, human immunodeficiency virus (HIV), human T lymphotropic virus, cytomegalovirus

Common Routes of Human Pathogenic Viral Transmissions ROUTE OF SOURCE/ MODE OF EXAMPLES/VIRUSES ENTRY TRANSMISSION Blood Insect bite Arboviruses, dengue virus, yellow fever virus, West Nile virus, encephalitis causing rbi Genital Genital secretions Hepatitis B virus, HiV, herpes simplex virus Urine Urine Polyomavirus(BK virus) e Conjunctival Adenovirus, cytomegalovirus, herpes simplex virus 1 Zoonotic Animal bite Rabies Arthropod bite Arboviruses Mammals excreta Arenavirus. hantavirus filovirus Chicken, wild birds-aerosol Avian influenza virus(bird flu, H5N1) droplet

Common Routes of Human Pathogenic Viral Transmissions ROUTE OF SOURCE/ MODE OF EXAMPLES/VIRUSES ENTRY TRANSMISSION Blood Insect bite Arboviruses, dengue virus, yellow fever virus, West Nile virus, encephalitis causing arboviruses Genital Genital secretions Hepatitis B virus, HIV, herpes simplex virus, cytomegalovirus Urine Urine Pol i ( i) lyomavirus (BK virus) Eye Conjunctival Adenovirus, cytomegalovirus, herpes simplex virus 1 Zoonotic Animal bite Rabies Arthropod bite Arboviruses Mammals excreta Mammals excreta Arenavirus hantavirus filovirus Arenavirus, hantavirus, filovirus Chicken, wild birds–aerosol droplets Avian influenza virus (bird flu, H5N1)

Vertical Transmission of Human Pathogenic Viruses SOURCE/ MODE OF EXAMPLES/VIRUSES RANSMHSSHON Prepartum or transplacental Cytomegalovirus, parvovirus B19, rubella virus human immunodeficiency virus(HIV) Intrapartum or during delivery/birth Hepatitis B virus, hepatitis C virus, herpes simplex virus, HIV, human papilloma virus Postpartum or via breast feeding Cytomegalovirus, hepatitis B virus, human T lymphotropic virus, HIV

Vertical Transmission of Human Pathogenic Viruses SOURCE/ MODE OF TRANSMISSION EXAMPLES/VIRUSES Prepartum or transplacental Cytomegalovirus, parvovirus B19, rubella virus, human immunodeficiency virus (HIV) I t t d i d li /bi th I n trapar tum or during d elivery/bi rth H titi B i h titi C i h Hepatitis B virus, hepatitis C virus, herpes simplex virus, HIV, human papilloma virus Postpartum or via breast feeding Cytomegalovirus, hepatitis B virus, human T l h t i i HIV lymp h o tropic virus, HIV

Major Patterns of viral Infections o Abortive infection(no progeny viruses) Lytic infection o Persistent infection Chronic infection Latent infection Most persistent infections have some kind of acute phase followed by either being eliminated from the host or becoming latent or chronic ● Viral transformation

Major Patterns of Viral Infections z Ab ti i f ti ( i ) Abortive in fection (no progeny viruses ) z Lytic infection z Persistent infection ¾ Chronic infection ¾ Latent infection ¾ Most persistent infections have some kind of acute Most persistent infections have some kind of acute phase followed by either being eliminated from the host or becoming latent or chronic z Viral transformation