Viruses

Question 1

Rotavirus

Answer 1

dsRNA virus-unique
most common cause of diarrheal disease among infants and children under 5
Nearly every child has been infected at least once by rotavirus by age 5

Question 2

Pathogenesis

Answer 2

most common in childern under 5
infects epithelial cells in small intestine
Viral replication,cell lysis, Disease

Question 3

Causes disease “Gastroenteritis”

Answer 3

Infects animals- not diseased until consumed by humans-pathogen of livestock
Transmitted by the fecal-oral route: Eating,Hands, Touching surfaces/objects that are contaminated
Viral shedding: during sickness,3 days after recovery

Question 4

Clinical manifestations

Answer 4

2 days after exposure: can last 3 to 8 days
Symptoms: Severe watery diarrhea-black or contain pus, Crying with few or no tears, Dry mouth +Throat,Unusual sleepiness/ fussiness

Question 5

Treatment + Preventation

Answer 5

Antibiotics are not effective, drink plenty of fluids, vaccination,oral rehydration, and rest
Handwashing important, vaccination

Question 6

Hepatitis B (HBV)

Answer 6

Taxonomy: Family- Hepadnaviridae
Structure: Enveloped virus,Icosahedral nucleocapsid, core

Question 7

Genome

Answer 7

Partially ds but not covalently closed (ccc)
complete -Dna strand +shorter +Dna strand
Single-stranded gap +Relaxed circular

Question 8

Transmission

Answer 8

Most common viruses: 2 billion people infected, 1 million die
Infects only humans and non-human primates
highly contagious: Exposure to infected blood+bodily fluids

Question 9

Infection

Answer 9

infects hepatocytes-liver cells
the only site of replication
travels through blood: separated from the bloodstream,infectious virions bind to receptors on hepatocyte surface

Question 10

Proteins

Answer 10

surface proteins: small ,medium, large (Enevolope)
Core protein: a structural component of nucleocapsid
Polymerase protein: DNA repair, reverse transcription
X protein: required for viral replication,virulence factor

Question 11

Replication

Answer 11

Nucleocapsid in cytoplasm to nucleus cccDNA
Rnas transcribed by cellular RNA pol
pregenomic RNA packaged into nucleocapsids
Reverse-transcribed by viral polymerase

Question 12

Persistance

Answer 12

Short and long term outcomes
immune response tries to clear infected cells
repeated cycles of injury and regeneration

Question 13

Disease

Answer 13

Hbv-related chronic liver disease-intergrated into own genome-liver cancer
symptoms don’t appear early:weight loss,loss of appetite,liver failure,etc.

Question 14

Treatment +Preventation

Answer 14

Vaccine +antiviral
Don’t share needles,get vaccinated, avoid sharing personal hygiene items

Question 15

Epstein Barr virus

Answer 15

Taxonomy: Herpesviridae
Structure: Enveloped, Icosaherdal nucleocapsid

Question 16

Genome

Answer 16

dsDNA linear
Encodes everything it needs: nucleotides
Tegument

Question 17

Transmission +infection

Answer 17

Salivia:kissing virus
Sharing glass or food utensils
Infects epithelial cells and spreads to tonsils
Salivary glands (epithelial) to lymphocytes (b-cells) tonsils

Question 18

Infectious mononucleosis

Answer 18

Latency in b cells, clonal expansion, T cells target infected b cells,Equilibrium reached-symptoms cease, can cause cancer

Question 19

Symptoms

Answer 19

incubation period of about 4 to 6 weeks,resolve overtime,swollen neck, abrupt onset of sore throat,etc.

Question 20

Treatment and prevention

Answer 20

No treatment or vaccine
Once have, have for life
Avoid kissing someone who is sick, don’t share personal items,wash hands

Question 21

Corona virus

Answer 21

SARS-coV2
Taxonomy: coronaviridae
Structure:Enveloped,helical nucleocapsid

Question 22

Genome

Answer 22

ssRNA linear
Structural proteins
nonstructural proteins-copy genome

Question 23

Transmission + Infection

Answer 23

infected person breathes out droplets that contain virus
-breathing in these, can land on the eyes,nose, or mouth, or contamination from infected surfaces
Infects lung epithelial cells

Question 24

Causes covid19

Answer 24

Viral replication: flu-like symptoms-immune response, cell death
sometimes no symptoms, sometime permanent loss
can be mild,moderate, or severe

Question 25

Treatment +prevention

Answer 25

Vaccine +antiviral treatments
Avoid people