Viral Pathogenesis Flashcards
What makes you feel bad?
Interferon response in body, thats why most of them feel similar
How do viruses damage host?
some are direct viral and others are effects of host trying to clear viruses
Viruses are caught from
each other in agriculture/livestock insect vectors food and water parents
what is a zoonotic infection?
transmitted from humans and animals
What are the major mechanisms of viral transmission?
respiratory, fecal-oral, contact: lesions, saliva, fomites, zoonoses, blood, sexual, maternal-neonatal, genetic
Why are zoonoses important?
they are an emerging source of many viral infections
What type of transmission is rare?
Genetic transmission like prions and retroviruses
What determine the severity of viral disease?
nature of exposure, viral dose (more virions, more sick), staus of person (age, general health, and immune status), and virus-host interactions
How do viruses enter, disseminate, and shed from host?
eyes, nose mouth; insect, skin injury; RT GI, GU
How do viruses infect in gut?
M cells sample the contents of the gut and present it to underlying immune cells; located on brush border; viruses infect M cell and easily reach the blood stream
Rotavirus is transmitted by?
fecal-oral
What is a virulence factor of rotavirus?
enterotoxin that causes watery diarrhea
How does virus dissemination happen?
may spread from surface of the body to lymph nodes and the blood stream
What is a primary viremia?
first point that virus can be detected in blood, during incubation; person may not feel sick
What is secondary viremia?
disseminates the virus to organs where it can shed
How does transmission occur?
direct contact or through the environment, or exposure to blood
VZV transmitted by
respiratory route
How is VZV disseminated?
infects epithelial cells and fibroblasts, spreads by viremia to skin, and causes lesions called chicken pox
Where was the majority of HIV-1 virus found?
blood plasma and lymphocytes, and CSF
Which has more HIV sperm or semen?
semen
What are the virus-host interaction outcomes?
can be unnoticed, cause illness, induce autoimmunity, be persistent or be lethal
What does a successful virus do?
evades destruction by the immune system and avoids destroying host before replication is finished.
What are the general patterns of infection?
acute, persistent latent, slow, transforming;
What are the 3 types of chronic viruses?
persistent, latent, and slow
