Sketchy Viruses Flashcards
Picornavirus:
What kind of virus are Picornaviruses?
Naked Positive sense RNA viruses
Picornavirus:
How are Picornaviruses transmitted?
Fecal oral transmission
*Except for rhinovirus which is through respiratory droplets
Picornavirus:
How do Picornaviruses replicate into proteins?
Host cell RNA polymerase
Picornavirus:
Where of positive sense RNA viruses replicate?
Host cell cytoplasm
Picornavirus:
What are the subfamilies of Picornaviruses?
Hepatitis A, Enterovirus, and Rhinovirus
Picornavirus:
What are the viruses under the subfamily Enterovirus?
Poliovirus, Coxsackie A and B, and Echovirus
Picornavirus:
What is the number one cause for aseptic meningitis?
Enteroviruses
Picornavirus:
What are the CSF levels for viral meningitis?
- Normal glucose
- no organisms shown (aseptic)
- Elevated proteins
Picornavirus:
What patient population are commonly affect by aseptic meningitis?
Children
Poliovirus:
Is the poliovirus acid stable or base stable?
Acid stable
Poliovirus:
Where does the Poliovirus replicate?
How long does it take to replicate?
- Peyer’s patches, located in the submucosa of the ileum. (Lymphoid tissue)
- 2-3 weeks
Poliovirus:
Where does the virus affect?
Anterior horn of the spinal cord causing asymmetric paralysis in the lower legs, myalgias, and decreased deep tendon reflexes.
If the virus ascends, causes respiratory insufficiency from paralysis of the diaphragm.
Poliovirus:
How can you treat the Polio vaccine?
- No treatment
- Prevent via Salk (killed vaccine) and oral Sabin (live attenuated) vaccine
Poliovirus:
What are the differences between the Salk and Sabin vaccines?
Salk only produces IgG antibodies whereas Sabin produces IgA and IgG. Because Sabin is live attenuated, there’s a risk of spreading the virus via fecal oral causing paralysis in another individual.
Coxsackievirus:
What kind of rash would you see in Hand foot mouth disease?
Red vesicular rash
Coxsackievirus:
When do infections commonly occur?
In the summer months
Coxsackievirus:
What can Coxsackie B virus cause?
Dilated Cardiomyopathy
* Also the devil’s grip: Bornholm’s disease/ Pleurodynia: an extreme sharp unilateral lower chest pain that makes it hard to breathe
Coxsackievirus:
How do you treat coxsackie viruses?
Supportive treatment dw about it on test day, know clinical features.
Rhinovirus:
Is rhinovirus acid stable or acid labile?
Acid labile, cannot survive the GI tract.
Rhinovirus:
Why is washing hands important in preventing Rhinovirus?
Transmission through fomites (objects of carry ie utensils, furniture)
Rhinovirus:
How does rhinovirus enter the body?
Attaching itself to ICAM-1
Rhinovirus:
What temperature does Rhinovirus like to grow?
Cooler temperatures around 33 degree C, which is why the upper respiratory tract is where it likes to grow because of constant ventilation
Rhinovirus:
Why is it difficult to make a vaccine for Rhinovirus?
Too many serotypes (113!)
Hepatitis A:
How does Hep A present clinically?
- Nausea and vomiting
- Jaundice
- Anicteric hepatitis in young children and infants
- also avoidance to smoking tobacco (INTERESTING!)
Hepatitis A:
Describe the symptom duration and resolve of Hep A:
- symptoms typically last less than 2 months
- virus is self limited
- no carrier or chronic state
Hepatitis A:
How can Hep A be prevented?
Inactivated vaccine
Hepatitis A:
Which pt populations are considered high risk for contracting Hep A?
- living in endemic areas
- chronic liver disease
- homeless
- men to men sexual relations
- IVDA
Calicivirus:
What kind of virus is Calicivirus?
Naked Positive sense RNA virus
Calicivirus:
What are the viruses under Calicivirus?
Norovirus/Norwalk Virus
Calicivirus:
What patient population are typically affected by Norovirus?
- People of close compartments ie cruise ships
*Responsible for over 90% of all outbreaks of diarrheal illness on cruises - Also young children at daycare/schools
Calicivirus:
How is Norovirus transmitted?
Eating shellfish and touching
Calicivirus:
What kind of gastroenteritis is caused by Norovirus?
Explosive diarrhea
Flaviviridae
What kind of virus is the Flaviviridae virus?
Enveloped Positive sense RNA virus
Flaviviridae:
How many Flaviviridae families are there?
5
Flaviviridae:
What are arboviruses?
Viruses transmitted through a vector like a tick or mosquito. An arthropod born virus.
Flaviviridae:
Name the different arboviruses:
- ## Dengue virus
Flaviviridae:
What vector does dengue virus transmit through?
Aedes aegypti mosquito
Flaviviridae:
What does Dengue fever cause?
Attacks the bone marrow so you would see thrombocytopenia, hemorrhagic fever, renal failure, septic shock, and death
Flaviviridae:
How can you treat Dengue Fever?
- No definitive treatment
- Avoid mosquitoes
- a tetravalent live attenuated vaccine is available in endemic but patient must have a confirmed previous dengue infection or else no infection prior can cause deadly infection (DONT GIVE SHOT UNTIL UR DAMN SURE THEY HAD DENGUE)
Flaviviridae:
What is the vector for yellow fever?
Aedes aegypti mosquito
(Same as dengue)
Flaviviridae:
What can yellow fever cause?
- jaundice
- lumbosacral pain
- bloody diarrhea
- bloody vomiting
- epistaxis, gingival bleeding, petechiae, and ecchymosis
- low platelet counts and abnormal coagulation
Flaviviridae:
How is yellow fever prevented?
- avoid mosquito bites
- live attenuated vaccine for travelers
Flaviviridae:
How is the Zika virus transmitted?
Aedes aegypti mosquito
Flaviviridae:
How can Zika virus spread once in the body?
Vertical and sexual transmission
*Virus can cross the placenta
Flaviviridae:
Describe Congenital Zika syndrome:
Microcephally, undeveloped brain tissue and neurological dysfunction.
Flaviviridae:
How does Zika virus present?
Fever, rash, conjunctivitis
Also can cause Guillain Barre syndrome
Flaviviridae:
What is the reservoir for West Nile virus?
Birds
Flaviviridae:
What is the vector for West Nile virus?
Culex spp mosquito
Flaviviridae:
What symptoms would you expect with West Nile virus?
- 80% asymptomatic
- 20% fever, nausea, body aches
- rarely can cause encephalitis
- Meningitis which can lead to acute flaccid paralysis
- seizure and movement disorders mimicking Parkinson’s Disease
- coma
Flaviviridae:
How can you diagnose West Nile virus?
PCR and Serology on CSF
Flaviviridae:
Which arbovirus is Mc seen in the US?
West nile virus
Flaviviridae:
What kind of Virus is Hepatitis C?
Enveloped Positive sense RNA virus
Flaviviridae:
What is the key virulence factor for Hep C?
RNA dependent RNA polymerase which lacks proofreading exonuclease activity. Meaning it mutated really quickly to evade the immune system.
Process of ‘antigenic variation’
Flaviviridae:
How is Hep C commonly transmitted?
Sharing needles and blood transfusion.
Flaviviridae:
How can you determine Hep C in its acute phase (<6mo)?
Fluctuating ALTs
- also nonspecific symptoms: nausea, jaundice, upper right quadrant pain, or low grade fever
Flaviviridae:
What can chronic Hep C progress to?
Liver cirrhosis and HCC
Flaviviridae:
How can you diagnose Hep C?
- HCV Ab screening test
If positive, - HCV RNA screening test
- +RNA test = active infection
- if Negative Ab test and + RNA test, occult infection whether window period or immunocompromised
- if negative for both test and still suspecting exposure, recheck at one, three, and six months
Flaviviridae:
How can you treat Hep C?
- Direct antivirals
- Vaccinate against Hep A and Hep B
Flaviviridae:
If a pt with Hep C progresses to cirrhosis, what do you routinely check?
Serum AFP, alpha FETO protein, and liver ultrasound to detect for HCC
