Micro Exam 1

What type of genome does Measles have?

(-)ssRNA

Is measles enveloped or non enveloped?

Enveloped

what are the 6 classical childhood exanthems? (rash causing viral illness)

1, Measles

2. Scarlet Fever

3. Rubella

4. Dukes’ Disease

5. Erythema Infectiosum

6. Roseola Infantum

What makes measles high contagious?

shedding before and after symptom onset through aerosol droplets

What are the 3c’s of measles

Cough, Coryza (nose inflammation), Conjunctivitis (red face)

What symptom is pathognomonic for measles

Koplik Spots in mouth

what is conjunctivitis a symptom of?

Measles

• one of the 3c’s

Where are koplik spots found?

On the Buccal Mucosa opposite the 1st and 2nd upper molars

What type of rash does measles cause?

Maculopapular Rash

What are the most common cause of death in Measles patients. Children and Adult

Children - pneumonia

Adult - Encephalitis (brain swelling)

How are measles diagnosed (3 things)

1. Clinically (usually)

2. IgM ELISA (IgM appears first)

3. RT-PCR (RNA virus)

What can be given to children with Measles to reduce severity?

Vitamin A

What type of genome does Mumps have?

(-)ssRNA

Name the genomes of Mumps, Measles, Rubella?

Mumps - (-)ssRNA

Measles - (-)ssRNA

Rubella - (+)ssRNA (outlire)

Is Mumps enveloped or non enveloped?

enveloped

What receptors does Mumps Bind?

Sialic Acid

Which 2 viruses we have covered uses Hemagglutinin (HA) and or Neuraminidase (NA) HN

Influenza A&B

Measles

Which Virus can shed in urine for up to 14 days after onset?

Mumps

Parotitis is the most common feature of what diseases

Mumps

Menigitis, Oophoritis (ovary swelling), Orchitis (ball swelling), and Encephalitis are common symptoms of what virus?

Mumps (2)

What type of genome does Rubella have?

(+)ssRNA, linear

(odd one out in MMR)

Which of the MMR is a very dangerous Teratogen (vertical Transmission)

Rubella

How could Rubella be distinguished from Measles?

Rash resolves within 3 days with usual lifelong immunity

At what time is Rubella usually cause CRS?

First Trimester

What virus is Petechiae common for?

Rubella

• not specific but common

How are the MMR diagnosed?

Usually Clinically with IGM ELISA and RT-PCR

What type of genomes does HPV (human Papillomavirus) have?

dsRNA, circular

What determines viral tropism?

Spike proteins that bind host receptors

The spike proteins on SARS-Co2 bind what host receptor

ACE2

Which form of RNA can be translated immediately by ribosomes?

(+)ssRNA

What is needed to turn (-)ssRNA into (+)ssRNA?

RNA-dependent RNA Polymerase

Influenza A has a segmented genome and goes through reassortment which cause _______ which leads to Pandemics

Antigenic Shift

(major changes, abrupt genetic change)

Which mutate faster, RNA viruses or DNA viruses? Why?

RNA viruses

• due to lack of proofreading

• Leads to Antigenic Drift

Antigenic Drift vs Shift

Drift - gradual changes in virus’s surface that may escape immunity

Shift - major, abrupt changes often from re-assortment from different viral species creating completely new strain, leads to pandencs

What is the difference between the entry of Enveloped vs Naked viruses?

Enveloped viruses can enter via fusion and endocytosis

Naked viruses exclusively enter through endocytosis, not direct fusion

• naked viruses can directly penetrate and inject but do not enter

which are more environmentally stable naked or enveloped?

Naked

• not susceptible to acids, detergents, drying, heat because they do not have a lipid bi layer that is easily disrupted

What are CPE’s and give examples?

visible changes or damage (with microscope), does not differentiate between viruses

examples - Inclusion bodies, syncytia, lysis, apoptosis

Which two viruses cause oncogenesis and how?

HPV and EBV

• Able to perform transformation and integrates straight into host genome

What needs to occur before uncoating enveloped viruses? How is this different from Naked

Fusion

Naked - do not have to enter the cell in order to release viral genome

What is the function of Type 1 interferons?

first line defense. released by cells when cell detects viral infections. triggers transcription/production of antiviral genes

What is Acyclovir used for and how does it work? What class of drug is it?

ProDrug - needs viral enzymes to activate it

used to treat HSV and VZV

• Nucleoside analog, NRTI

Drugs that end in -NAVIR are protease inhibitor, what are protease inhibitors commonly used to treat?

Protease Inhibitors

Used to treat HIV by preventing maturation

example - Atazanavir, Darunavir

NRTI vs NNRTI

NRTI - mimic natural nucleosides (example Acyclovir)

NNRTI - bind directly to reverse transcriptase

What is the primary infection of VZV and what is the reactivation?

Primary. - Chicken Pox

Secondary - Shingles

What virus causes Mononucleosis (mono)?

EBV

(also known as HHV-4)

What cells does EBV infect?

B Lymphocytes

Which virus causes Owl’s eye inclusions?

CMV

(also know as HHV-5)

What form of herpes causes Malignacy (tumor/cancer) in HIV patients?

HHV-8

HPV 1,2,4 cause what?

Skin warts (not genital)

Koilocytes are CPEs characteristic of what virus?

HPV

What does HPV 6,11,42,43,44 cause?

genital warts

• mostly 6 and 11

If wart are found on the bottom of the feet what type of HPV is it likely to be?

HPV 1

What are the 4 major components of the Oral Microbiome?

Oral bacteriome

Oral Mycobiome (fungi)

Oral virome

Oral Parasitology

What species of fungi predominates the oral cavity?

Candida

“Candida Albicans”

What fungi is present in healthy oral cavities?

Malassezia

What can Candida Albicans grow as?

Hyphae (mold) or Yeast

Are Candida prokaryotic or Eukaryotic

Eukaryotic

• reproduce sexually or asexually

what is the 2 substantial human defenses against fungi?

37 degrees Celsius - too high for fungi growth

Innate and Adaptive Immune cells

What do Polyenes (Amphotericin B) target

Bind Ergosterol

(toxic side effects possible)

What to Azoles (ketoconazole) target

inhibit ergosterol synthesis via cytochrome P450

What do Allylamines (Terbinafine)

inhibit squalene epoxidase

(fungi specific)

What do Echinocandins (Micafungin) target

inhibit B-Glucans in cell walls

(less side effects)

What major drug target is in the cell wall of fungi?

Ergosterol

True or False Candida have cell wall

True or False Cryptococcus havecell wall

True or False Aspergillus have cell wall

True

True (also has a capsule

True

What is Dimorphic Transition?

a type of virulence where fungi change from Yeast to Hyphae for tissue penetration

What type of viral infection is seem in AIDS patients?

HHV-8 or Kaposi’s Sarcoma

If you had a patient suffering from a naked virus spread primarily through the oral fecal route, what two viruses would you test for first?

Rotavirus and Norovirus

Out of Rotavirus and Norovirus, which has a vaccine available?

Rotavirus

what are the components of a virus/make up a virus?

genome (DNA or RNA), capsid (protein shell), lipid envelope (some), spike proteins

What determines viral TROPISM

spike proteins

Which are more environmentally stable Naked or Enveloped viruses?

naked

• more stable against, heat, acid, and detergents

What are the 3 primary shapes of viral capsids

icosahedral (primary)

Helical

Complex

What type of viruses mutate faster due to lack of proofreading?

RNA viruses

What type of test would you used to detect CTEs like syncytia and Cowdry Bodies

Tzanck’s smear

• not viral specific methods

What is the main goal of a Neuraminidase inhibitor?

prevent viral release

• used largely in flu treatment

Of Hep A, B, and C which are acute risk and chronic risk

Hep A only acute infection

Hep B/C chronic risk

What are the most common viral oral infections

HSV and HPV

what are the smalled human viruses?

Picornaviridae

Picornaviridae are naked or enveloped, why?

naked

• infect and shed in the intestinal tract VERY resistant to hard conditions (stomach pH, sewage systems)

What characteristic do enteroviruses share?

the ability to infect the intestinal tract and shed viruses without causing GI diseases

What is an enterovirus that doesn’t spread through the fecal oral route?

Rhinovirus A,B,C

What are the important members of the Picornaviridae (enterovirus) family?

poliovirus

enterovirus

coxsackievirus

echovirus

rhinovirus A,B,C

What age does Coxsackie virus affect?

mostly occurs children <5

• increased summer incidence

What is true of most Coxackie infections

asymptomatic or mild

What is the leading cause of chronic hepatitis?

Hep B

What virus causes Hands-Foot-Mouth disease?

highly contagious

What 3 Clinical symptoms are caused by coxsackies?

1. Hands foot and Mouth

2. Herpangia (sores on back of throat and palate)

3. Acute hemorrhagic conjunctivitis (eye swelling, mucoid discharge)

Whats foot and mouth can be caused by coxsackies and what other virus?

enterovirus 71 (southeast Asia)

What differentiates HFMD from Herpangina?

HFMD causes lesions on the anterior part of the mouth

Herpangia is the posterior part of the mouth

What differentiates HSV lesions from Herpangina?

HSV legions are anterior part of mouth

Herpangina are in the back of the throat

How many types of adenovirus cause disease in humans?

57

What virus cause THE MOST common cause of viral conjunctivitis?

Adenovirus

(Cold/conjunctivitis/Epidemic Keratoconjunctivitis)

How does Adenovirus spread

through Aerosols

Fecal Oral

Direct Contact

(never fucking dies, 5 weeks on inanimate objects)

What virus can spread through pools?

Adenovirus

In what part of the body does the Adenovirus infection occur in and what type of infection is it?

persist and lymphoid

latent infection

what is Pharyngoconjunctival fever, what is it caused by, what symptoms does it cause?

combination of adenovirus, URT infection and conjunctivitis

causes fever, malaise, cough, sore throat, nasal congestion, follicular

common in children

What is Keratoconjunctivitis (EKC) caused by

Adenovirus

(pathognomonic for adenoviral infection)

What types of Adenovirus are treated with vaccine?

types for 4 and 7

What HIV type causes the most causes in US

HIV-1

How is most HIV spread?

Majority through sexual contacts (gay men)