Micro Bio FSC Exam 2 List

important stuff

List Viral Components

Virus Particle

Covering

1. Capsid (protein)

2. Envelope

Inner Core

1. Nucleic acid molecule (DNA or RNA)

2. Various Proteins (enzymes)

Identify Different Types of Viral Structure

Helical

Polyhedral

Spherical

Complex

Describe how viruses are classified

Named on capsid structure, chemical composition, and genome type

Virus Families

-viridae

Virus Genera

-virus

Describe and Order the steps of Animal Virus Replication

1. Adsorption

2. Penetration (Endocytosis or Fusion)

3. Uncoating

4. Production of Viral Components (Synthesis)

5. Assembly

6. Release (Budding, Exocytosis or Lysis)

Adsorption

The virus attaches to its host cell by specific binding of its spikes to cell receptors

Penetration

The virus is engulfed by the cell membrane into a vesicle or endosome and transported internally

Endocytosis

Viral particle engulfed into vesicle

Fusion

Viral particle’s cell envelope fuses with host’s cell membrane and nucleocapsid is released into the host

Uncoating

Conditions within the endosome cause fusion of the vesicle membrane with the viral envelope, followed by release of the viral capsid and RNA into the cytoplasm

Synthesis

Under the control of viral genes, the cell synthesizes the basic components of new viruses; RNA , capsomers, and spikes

Assembly

Viral spike proteins are inserted into the cell membrane for the viral envelope; nucleocapsid is formed from RNA and capsomers

Release

Enveloped viruses bud off of the membrane, carrying away an envelope with the spikes. This complete virus or virion is ready to infect another cell

Budding

Viral capsid pinches off covered in viral envelope

Exocytosis

1.Newly made viral proteins on rough ER transported to the Golgi Body

2.Membrane with viral proteins buds inside of golgi body while surrounding viral genome

Vesicle with virus inside

3. Vesicle fuses with cell membrane

4. Virus leaves cell

Lysis

Cell bursts with viral particles (deadly)

Describe 2 types of viral entry

Endocytosis & Fusion

Compare and Contrast 3 different types of Viral Release

• Budding = enveloped viruses “steal” membrane while leaving cell alive.

  • Cell is enveloped

  • Cell membrane

• Lysis = naked viruses burst cell open.

  • Cell dies

• Exocytosis = enveloped viruses use vesicular trafficking to exit.

  • Cell usually enveloped

  • rough ER and Golgi Body

Describe and Identify 4 types of Viral Infections

Acute Infection

Latent Infection

Chronic Infection

Transformation into malignant cell

Acute Infection

Rapid multiplication

Cell death and virus release

Latent Infection

Viral components are present (e.g., viral genome) host is not harmed

leading to acute infection

Chronic Infection

Slow release of virus without cell death

Transformation into malignant cell

Activation of host proto-oncogene, insertion of oncogene, or inactivation of tumor suppressor protein

Define ‘plaque’

Virus replication lyses bacterial cells creating ‘plaques’

Essentially the absence of cells in a cell cultureDe

Describe 3 methods of viral propagation

1. Viruses are cultivated in ‘lawns’ of other cells

2. Cultivated in bird embryos (vitro)

3. Injected into live animals (mice)

   1. Viral plaque culture injected

Explain 3 methods of Viral Detection

1. Infect Cell Culture and then look for plaques or cytopathic effects

2. Screen for parts of the virus

   1. ex: DNA or RNA via quantitative PCR (molecular test)

   2. ex: viral antigens via antibod-based tests (rapid test)

3. Screen for immune response

   1. ex: antibodies against the virus (serological test)

Interpret results of Rapid Antigen test data

1. Microscopically contains a paper with antibodies that bind to virus (reporter antibodies)
2. Test line has antibodies that bind to virus
3. Control line has antibodies that bind to reporter antibodies
4. When sample (virus) is added, capillary flow will travel from reporter antibodies towards test line and control line

Positive Rapid test

Test line grabs COVID particles

Control line grabs reporter antibodies

Creates 2 lines

Negative Rapid Test

Test line grabs NOTHING
Control line grabs reporter antibodies
Creates ONE line for the test line since NOTHING is detected and one line for the control line since it detected the reporter antibodies

Understand Epidemiology (virus characteristics, disease signs, treatments, transmission) of skin and systemic viruses

Small Pox, HSV1, HSV2, Varicella-Zoster, Epstein-Barr, HPV, Measles, Mumps, and Rubella

Smallpox Characteristics

aka Variola Virus

DNA virus, eveloped

Hourglass capsid

Smallpox Tropism

Skin epithelial cells

Subcutaneous connective tissues

Smallpox Signs

Prodromal Stage: Fever, malaise

Eruptive stage: Pocks all over body

New pocks are pus filled

Healed pocks leave scars

Toxemia > Hemorrhaging

Smallpox treatment

Vaccinia virus (vaccine)

Smallpox Reservoirs / Transmission

Humans only reservoir

Inhalation of saliva droplets

Pock Crust

Fomites

Herpesvirus Characteristics

DNA, enveloped virus

All show latency and cause recurrent lytic infection

Herpesvirus Tropism

Varies between glands, lymph, and ganglia

Typees of Herpesvirus

Herpes Simplex 1 (HSV 1)

Herpes Simplex 2 (HSV 2)

Varicella-Zoster (Herpes 3) (AKA Chicken Pox)

Epstein-Barr (Herpes 4)

HSV 1 types of infection

Herpes labialis (cold sore)

Ocular Herpes

Neonatal encephalitis

HSV-1 Site of Latency

Trigeminal Ganglia

HSV-1 treatment/prevention

Acyclovir, Valacyclovir (NOT A CURE)

HSV 2 

Genital Herpes

HSV-2 Transmission

Direct contact ESPECIALLY SEXUAL CONTACT

HSV 2 Types of infection

Herpes Gentalis

Neonatal ecephalitis

HSV-2 Site of latency

Sacral Ganglia

HSV2 Treatment / Prevention

Barriers (i.e., condoms)

Acyclovir, Valacyclovir (NOT A CURE)

Varicella Zoster Virus

Herpes 3 / Chicken Pox

Varcella Zoster Transmission

Direct Contact, respiratory droplets

Varicella Zoster Signs/Symptoms

Asymptomatic in respiratory tract

Incubation period 10-20 days

Rash > blisters on face and torso

Herpesvirus 4 (Epstein-Barr Virus)

Infectious mononucleosis

‘mono’

Varicella-Zoster Site of Latency

Ganglia

Varicella Zoster Treatment / Prevention

Acyclovir

Varivax Vaccine or MMR-V

Varicella Zoster primary infection

Chicken pox

Varicella Zoster recurrent infection

Shingles

Shingles signs/symptoms

Pain

Rash > blisters on face and torso

Epstein-Barr virus site of latency

B cells

Epstein-Barr primary infection

Infectious Mononucleosis

Epstein-Barr signs/symptoms

High fever

Swollen lymph nodes

Extreme Fatigue

Epstein-bar transmission

Direct contact (via saliva)

Epstein-Barr treatment

DNA Synthesis inhibiting anti-viral drugs (Acyclovir, Famcyclovir, Valacyclovir)

Explain how Acyclovir inhibits herpes replication

Acyclovir looks like a nucleotide, but another nucleotide cannot be added to it during DNA synthesis thus blocking viral DNA synthesis

Explain why Acyclovir cannot cure herpesvirus infections

Stops DNA synthesis of the virus, the virus is already present. Prevents its production. Reduces time that blisters appear

Reduces risk of transmission does NOT remove latently infected cells

Human Papillomavirus

HPV

HPV Characteristics

DNA virus

Non-enveloped

Oncogenic

100+ strains

HPV Tropism

Epithelial cells

Seed wart

Painless, elevated, rough, growth on hands and fingers

Plantar Wart

Depp, painful growth on soles of foot

Genital warts

Common STI, various morphologies (tiny and flat to cauliflower-like growth)

HPV types of Disease

Warts

Cancer

HPV treatment / prevention

Physical Removal

Cauterization

Freezing

Laser

Chemical Treatment: Gardasil, Cervarix

HPV transmission

Direct contact and fomites

List 2 strains of HPV with highest cancer risk

HPV 16 and HPV 18

Measles, Mumps, Rubella

MMR

All childhood diseases, preventable with one effective vaccine

MMR Characteristics

RNA

enveloped viruses

MMR Transmission

Via respiratory droplets

Measles aka

Rubeola

Measles caused by

Morbillivirus

Measles signs/symptoms

Systemic skin rash, oral lesions, high fever

Measles major complications

Pneumonia

Ecephalitis

Rubella aka

German measles

Rubella caused by

Rubivirus

Teratogenic

Teratogenic

Can cross the placenta

Rubella signs/symptoms

Systemic skin rash

Rubella Major complications

Miscarriage

Various birth defects

Mumps aka

Epidemic Parotitis

Mumps caused by

Orthorubulavirus

Mumps signs/symptoms

40% of cases asymptomatic

Painful swelling of salivary glands

Mumps major complications

Deafness, infertility (inflammation of gonads)

Define latency

dormant state of viral infection in which the virus remains present within host cells but does not actively replicate or produce new viral particles.

Compare and contrast Gentalis vs labialis herpes

Herpes labialis is HSV-1, coldsores, triggered by stress, spread through oral contact, treatment is majorly acyclovir

Herpes gentalis is HSV-2, genital herpes, random recurrances, spread through sexual contact specifically genital area, treatment is barriers and acyclovir

Describe differences between chicken pox vs shingles

Chicken pox is the primary infection of Varicella Zoster, demographics are majorly children, asymptomatic in respiratory tract, incubation 10-20 days,

Shingles is the recurrent infection of Varicella Zoster, demographics are majorly elderly

Same prevention, acyclovir and varivax vaccine. Both leads to rashes/blisters on face and torso

Name 1 Oncogenic DNA virus

HPV-16 leads to a lot of cancers like cervical cancers, anal cancers most prevalent in men

Name 1 teratogenic virus

Rubella aka German measles

Differentiate between measles, mumps, and rubella

All caused by different viruses

Measles - morbillivirus

Mumps - orthorubulavirus

Rubella - rubivirus

Measles can cause fevers

Mumps is most unique with swelling of salivary glands

Rubella is majorly systemic skin rashes

Measles major complications are pnuemonia and ecephalitis

Mumps major complications are deafness and infertility

Rubella major complications are miscarriage, various birth defects

Define MMR Vaccine

Primarily given during childhood to prevent Measles, Mumps, Rubella and all childhood diseases

Understand Epidemiology (disease triangle) of Enteric- and/or Neuro- tropic Infections

Hepatitis A

Hepatitis B

Hepatitis C

Norwalk virus (norovirus)

Poliovirus

Hepatitis Viruses

Very different viruses but all have liver tropism

Hep A

Hep B

Hep C

Hepatitis A characteristics

RNA, non-enveloped virus

Hepatitis A caused by

Enterovirus 72