Exam IV: How to be a Virologist Flashcards
What is the structure of HCMV? Enveloped? Diameter? Shape?
Enveloped
150-200 nm in diameter
Iscoaherdral
What is the genome of HCMV? how long is it?
linear dsDNA
200kb
What family does HCMV belong to?
Herpesvirus
What is the mode of transmission of HCMV?
Direct contact with bodily fluids
What is the R0 of HCMV?
1.7 (1 person will infect ~2 others)
What is the host of HCMV?
Humans
What is the tropism of HCMV? (4)
- Epithelial cells
- Endothelial cells
- Fibroblasts
- Leukocytes
What is the mechanism of penetration of HCMV?
glycoprotein H (gH), gL, gO from a trimer compelx on the envelope and bind to gH/gL receptors
What is the life cycle of HCMV?
Entry > nuclear por > vDNA release into nucleus > trancription and translation > DNA replication via rolling cirlce mechanism > linear concatemer > cleaved into single copies > assembly in nucleus > buds otu of golgi
What are 2 unique features of HCMV?
- UL42 protein inhibits cGAS/STING pathway (delays recognition)
- HCMV goes latent in myeloid cells by incorporating into host genome
What disease does HCVM cause (2)? Symptoms?
Mild illness: fever, sore throat, fatigue, swollen glands
Can cause mononucleosis and hepatitis
What is the most common patient outcome with HCVM?
HCVM will go latent with occasional reactivation
__% of the population is infected with HCVM in developed countries. About __% in undeveloped countries.
60% developed
90% undeveloped
What is the epidemiology (geographic distribution) of HCMV?
Rocky mountians, midwest, northern-most northeast
What is the seroprevalence of HCMV?
60% of US population
What is the likelihood of reinfection of HCMV?
Reinfection rate ~10%
What is the treatment for HCMV?
Not generally needed
If you are immunocompromised: antivirals
What are preventative measures against HCMV?
Avoid contact with another person’s bodily fluids (don’t share drinks, wear a condom, etc)
Where does HCMV do latent?
Goes latent in Myeloid (monocyte) progenitors
Is the tissue HCMV goes latent in different from the tissue it infects?
It can be??
Are enzymes brought in with the capsid of HCMV?
Yes (pp65m, pUL47, pp150, pp28, pp71)
Direct things toward nuclear complexes
What are the diagnostic tools for HCMV?
Detect antibodies using ELISA assay
If less than 1 year old: PCR of saliva with urine sample for confirmation
What are the public health concerns for HCMV?
1/200 people is born with congenital HCMV
Long term health problems include hearing loss, developmental/motor delay, vision loss, microcephaly, seizures
What are medically related complications to HCMV?
Retinitis (inflammation of the retina), colitis, esophagitis, hepatitis, encephalitis, pneumonia
How might HCMV become a problem in the health care setting? (3)
Congenital infection with 32% transmission rate
Contributes to mortality in AIDS patients
Most common opportunity in transplant patients
What is the genome of Chikungunya Virus made of? How long is it?
+RNA
11.8 kb
What is the structure (morphology) of Chikungunya virus? Enveloped? How many protiens does it code for?
Small (70 nm)
Enveloped
9 protiens
What family is Chikungunya a part of?
Togaviridae Family
What is the mode of transmission for Chikungunya?
Arbovirus
Aedes aegypti mosquitos
What is the R0 of Chikungunya?
3.4
What are the hosts of Chikungunya?
Humans
Mosquitoes
What symptoms does Chikungunya infection have?
Fever and joint pain
also headache, muscle pain, joint swelling, rash
What is the incubation period for Chikungunya virus?
3-7 days
What are the patient outcomes of Chikungunya infection?
Severe and debilitating joint pain
Most symptoms subside after 1 week
Are enzymes brought in with the capsid in Chikungunya?
No, but the capsid protein itself is autoproteolytic
What are the diagnostic tools for Chikungunya infection?
Antibody test
Antigen test for viral RNA
Symptoms are indistinguishable from dengue and zika virus
What are the public health concerns of Chikungunya?
With climate change, the range of its vectors (monsquitoes) is increasing
Does Chikungunya undergo latency?
No
Tell me about the lytic infection of Chikungunya
Lytic infection set in for 2-4 days
Replicates in fibroblasts
travels through the blood to liver, muscle, joints, lymphoid tissue, brain
What is the most distinct symptom of Chikungunya?
Arthralgia
Is Chikungunya a persistnat infection?
Yes, it can be found after 44 days in splenic macrophages and enothelial cells
What are 4 important proteins for Chikungunya life cycle?
- nsP1
- nsP2
- nsP3
- nsP4
What is the lifecycle of Chikungunya?
Four nsPs come together with viral RNA and host protiens > form replication compartments at the cell membrane (spherules) > genome is replicated > spherules are internalized > leave vacuoles to form mature virus > virus buds out and egresses
What are the medically related complication of Chikungunya?
Long-term complications: joint pian, muscle pain, joint stiffness, joint swelling
Rare complication: eye inflammation, myocarditis, myelisis, cranial nerve palsies
How might Chikungunya become a problem in a health care setting?
The acute symptoms are debilitating and extremely painful
Long term chronic pain management
Contribute to a decrease in the quality of life
What is the treatment for Chikungunya?
Supportive care
Prevention of Chikungunya?
Avoid getting bit by mosquitos
No vaccine
Likelihood of reinfection
Immunity should last for life
What regions of the world has the highest prevelance of Chikungunya?
Southeast Asia
Seroprevalacnce of 22%
