EXAM 1- HUSSEIN

ONLY BASED ON SG

Describe the Lytic cycle of viruses/bacteriophages:

• what happens to the host?

• host’s membrane is damaged, cytoplasm leaks out

• host cell RAPIDLY dies, releases virus particles

Describe the Lysogenic cycle of viruses/bacteriophages:

• what happens to the host?

• what does the virus to the host?

• what period does the viral infection enter during this period?

• host cell is NOT killed immediately—> instead is occupied by the virus

• virus uses host as a “factory” for replicated viral genes

• viral infection enters “latent” period during this process

What virus leads to mononucleosis and Burkitt lymphoma?

EBV/ HHV-4

OVERACTIVE immune response to EBV leads to ________________.

a. mononucleosis

b. Burkitt lymphoma

a

WEAK immune response to EBV leads to ________________.

a. mononucleosis

b. Burkitt lymphoma

b

CMV or cytomegalovirus or HHV-5 leads to WHAT consequences in fetuses?

• disease? s/sx?

fetuses:

• CMV disease

• disease ranges from no defects to CYTOMEGALIC INCLUSION DISEASE

  • sym: jaundice, CNS damage

CMV or cytomegalovirus or HHV-5 leads to WHAT consequences in HIV/ AIDS pts.?

• ________ most common opportunistic infection in HIV

• disease? leads to?

HIV/AIDs:

• CMV retinitis (most COMMON opportunistic infection in HIV)

  • leads to: retinal detachment, blindness

Adenovirus can lead to what syndromes?

• acute hemorrhagic cystitis

• pharyngitis

  • usually w/ pink eye

• pink eye (conjunctivitis)

Acute hemorrhagic cystitis caused by adenovirus is most common in what group of people?

boys

Parvovirus B19 usually infects what age group?

pediatrics/kids

Parvovirus B19 usually causes what fever? what symptoms?

• slapped cheek fever

• sym:

  • lacy body rash

  • facial rash

ALL DNA viruses replicate where?

What is the 1 exception to this?

• ALL DNA viruses, replication occurs in the NUCLEUS

• EXCEPTION: pox virus—> replication occurs in the CYTOPLASM

What are the modes of infection for HPV (Human Papilloma Virus)?

• asymptomatic shedding

• direct contact

• SEXUAL CONTACT

• birth

• chewing

What is the major symptom of HPV?

• WARTS!!!!!!!!

  • common warts

  • genital warts

  • CONDYLOMA ACUMINATUM (cauliflower-like wart)

HPV can lead to what kind of cancer? vaccine?

• HPV can lead to CERIVCAL CANCER

• vaccine: HPV vaccine (Gardasil)

  • usually given to young girls

Chickenpox is caused by what virus?

Varicella Zoster Virus (VZV) or HHV-3

How does chickenpox compare in young vs. old pts.?

• which is there tx for?

• when do children get vaccinated?

• which age is the virus more severe in?

• young

  • no tx, only support

  • children vaccinated after 12m (live, attenuated)

• old

  • MORE SEVERE IN ADULTS

  • tx is antivirals

Chickenpox can reactivate later in life and this is called…

shingles or zoster

What is Shingles (Zoster)?

• severe pain where?

• limited to where?

• severe pain in the nerve precedes lesions

• limited to 1 DERMATOME (aka rash is limited to the skin supplied by that nerve, compared to chicken pox which is all over your body)

Chicken pox causes lesions that can break open and allow what bacteria to invade and cause secondary infections?

What can this infection lead to?

• bacteria: S. pyrogenes (GAS)

• S. pyrogenes infection can lead to NECROTIZING FASCIITIS

What are arboviruses?

• what are arthropods?

• infects who?

• transmits virus from ______

• “arthropod borne virus”

• arthropods= mosquitos, ticks, sandflies, etc.

• infects vertebrates and invertebrates

• transmits virus from SALIVARY GLAND in the arthropod

ONLY _________ can transfer arboviruses from human-human.

MOSQUITOS

What is the vector for St. Louis encephalitis?

Culex mosquito

When does St. Louis encephalitis occur primarily?

a. late summer, early fall

b. early spring, late summer

c. late winter, early spring

d. only in the winter

a

What are symptoms of St. Louis encephalitis?

• mild illness

• severe illness

• mild: fever, headache

• severe: neck stiffness, convulsions, spastic paralysis

  • aseptic meningitis, severe encephalitis

How is HIV transmitted?

How is HIV NOT TRANSMITTED?

• modes of transmission

  • blood, blood products (ex: needle drug injection)

  • sexual intercourse (semen, vaginal secretions)

  • vertical infection (mom—>baby)

  • iatrogenic (means HIV infections caused by medical interventions including unsafe procedures, contaminated blood, etc.)

    • Ex: healthcare prof reusing needles

• NO TRANSMISSION BY CAUSAL CONTACT OR FECAL-ORAL ROUTE!!!!!!!!

How is polio transmitted?

person to person like fecal-oral

What are the different forms of polio? paralysis?

• asymptomatic

• symptomatic (muscle weakness, paralysis)

  • paralysis type:

  • spinal polio

  • bulbar polio

  • bulbospinal polio

What are 2 available vaccines for polio?

Which is preferred?

Which is live? killed?

Which is PO? injectable?

• 2 VACCINES: SABIN AND SALK

• Sabin- live attenuated, oral, best

• Sulk- killed, injectable

What symptom is commonly associated with yellow fever virus and hepatitis? why?

• JAUNDICE!!!!

• bc these viruses mess with the liver

Common vector of yellow fever?

mosquitoooooooo

Rhabdovirus aka rabies is transmitted how?

• via infected saliva through BITE of rabid animals

  • dogs, raccoons, foxes, bats

How does the rabies virus reach the CNS?

travels along nerve fibers

What is the tx for rabies?

• symptoms present

• if suspected immediately after bite

• IF SYMPTOMS ARE PRESENT—> TOO LATE—> NO TX

• If suspected, immediately after bite

  • Post-exposure prophylaxis:

  • 1 dose of human rabies immunoglobulin (HRIG)

  • Vaccination with the killed virus vaccine: 5 doses of rabies vaccine (On day 1, 3, 7, 14, 28)

What is the name of the antibody used for rabies tx?

HRIG or human rabies immunoglobulin

When is vaccination used for rabies?

• in high risk groups

• used in pre/post-exposure prophylaxis

What are the symptoms of Measles?

• 3 C’s—> cough, coryza, conjunctivitis

  • coryza- cold, acute rhinitis

• Koplik spots (looks like salt grains in mouth)

• rash (maculopapular rash from ears down)

What is a rare, but serious complication of measles?

subacute sclerosing panencephalitis (chronic CNS degenerative disease)

How is measles transmitted? (not in pp, but on his study guide)

• Airbourne respiratory droplets

• direct contact with contaminated sources

Rubella can cause serious teratogenic consequences in the _________ trimester.

a. first

b. second

c. third

d. fourth

a.

What are the teratogenic consequences that can be caused by rubella? s/sx?

• CONGENITAL RUBELLA SYNDROME

  • group of physical abnormalities

  • sym: rash, low birth weight, heart abnormalities, visual problems, bulging fontanel MICROCEPHALY, PDA

How is the Hanta virus transmitted?

rodent feces/mouse droppings

Where in the US, is the Hanta virus most commonly seen?

Arizona, Colorado, New Mexico, Utah

What symptoms are commonly seen with ebola? is it deadly? most commonly found where?

• Sym: BLLEDING EVERYWHERE (HEMORRHAGE)

  • vomiting blood

  • bloody urine

• Deadly (>50% death rate)

• mostly seen in Africa

What virus is the primary cause of pneumonia in CHILDREN?

RSV

What virus is main cause of primary viral pneumonia and secondary bacterial pneumonia?

Influenza A

List all the viruses that can be transmitted SEXUALLY:

• HPV

• HSV-1, HSV-2, CMV/HHV-5 (herpes)

• HAV, HBV, HCV (hepatitis A-C)

• HIV

List the viruses that are oncogenic:

EBV, HBV, HCV, HTLV, HPV

For each virus that is oncogenic, list the cancer it causes:

• EBV—> Burkitt Lymphoma, nasopharyngeal carcinoma, lymphoma, thymic carcinoma

• HBV and HCV—> primary hepatocellular carcinoma

• HTLV—> “human T cell leukemia virus”—> leukemia/lymphoma

• HPV—> cervical cancer

For + stranded and - stranded RNA viruses what enzymes (if any), are required for each?

• + stranded: NO RNA-DEPENDENT RNA POLYMERASE REQUIRED inside the virus

• - stranded: YES, NEEDS RNA-DEPENDENT RNA POLYMERASE inside the virus

What is the strategy of replication used by + and - stranded RNA viruses?

RNA—> RNA

What is the infectivity ALONE of + stranded RNA and - stranded RNA?

• + stranded: INFECTIVE ALONE

• - stranded: NON-INFECTIVE ALONE

What is the MOA of Acyclovir and Ganciclovir? What is required for its conversion from prodrug to active form?

What are the uses for these antivirals?

• MOA: inhibits viral DNA replication

• prodrug that requires viral THYMIDINE KINASE for activation

• Uses: genital herpes and cold sores

Which of the following is a PROTEASE inhibitor?

a. Ritonavir

b. Amantadine

c. Oseltamivir

d. Zanamivir

a

What is HAART and what does it stand for?

• stands for “Highly Active Antiretroviral Therapy”

• it is a cocktail of 2 or more different classes of anti-HIV drugs

What is the MOA of Amantadine? What virus does it target?

• MOA: blocks the M2 ion channel

• specific for type A influenza aka the FLU

(think: Amantadine—> Influenza A, M2)

Which antiviral drug is teratogenic?

Amantadine

Oseltamivir (Tamiflu) and Zanamivir (Relenza) belong to what class? MOA? Which viruses?

Neuraminidase Inhibitors

• MOA: inhibit neuraminidase on influenza A AND B

Oseltamivir/Tamiflu can be used for tx and prevention. What is indication for treatment?

In pts. >1 given orally to tx uncomplicated infection in 1st 48 hrs

Zanamivir/Relenza can be used for tx and prevention. What is indication for treatment?

In pts. >5 given by inhalation to treat infection in the 1st 48hrs of symptoms

What animal prion disease occurs in sheep?

scrapie

What is the effect of UV light in scrapies?

not effective—>since prion diseases DONT have DNA/RNA, UV light is not very effective

Kuru is mainly transmitted how?

cannibalism in humans

What is an animal prion disease that occurs in cattle?

Bovine Spongiform Encephalopathy (BSE)

Which of the following is associated with consuming beef products with Bovie Spongiform Encephalopathy?

a. CJD

b. vCJD

b

Which of the following is an inherited disease that is genetically DOMINANT?

a. CJD

b. vCJD

a

Which of the following is associated with an age of onset in YOUNGER INDIVIDUALS (~28)?

a. CJD

b. vCJD

b

Which of the following is associated with an age of onset in OLDER ADULTS (60-68)?

a. CJD

b. vCJD

a

Which of the following is associated a slower progression and death occurs within 13-14 months after diagnosis?

a. CJD

b. vCJD

b

Which of the following is associated a faster progression and death occurs within 4-5 months after diagnosis?

a. CJD

b. vCJD

a

What are symptoms seen with CJD?

• cognitive impairment

• involuntary muscle movement

In CJD, the CSF contains ______________ protein, which is associated with prion disease.

14-3-3

What is a rare genetic disorder that is inherited, a prion disease, and affects the brain and CNS to cause severe insomnia, memory loss, and muscle twitching?

familial fatal insomnia

Familial fatal insomnia occurs because of a mutation in _______gene.

PRNP

How is active immunity acquired?

through natural infection or by vaccine

Active immunization results in _______________.

a. short and long term immunity

b. permanent, long lasting immunity

c. short, rapid term protection

b. permanent, long lasting immunity

What is responsible for the long-term effects of vaccination?

memory cells

List examples of passive immunization:

• Hepatitis A

• treatMENT of exotoxin diseases (tetanus, diptheria, botulism)

A conjugative vaccine is _____________ + _______________.

polysaccharide + protein carrier

Which of the following is a conjugative vaccine:

a. Haemophilus Influenzae Vaccine (Hib)

b. Tetanus toxoid vaccine (TT)

c. Inactivated polio vaccine (IPV)

d. Measles, mumps, and rubella vaccine (MMR)

a- Hib VACCINE!!!!!!!!!!!!!!!!!

What is the tetanus vaccine?

a. Conjugate vaccine

b. Live attenuated vaccine

c. Toxoid Vaccine

d. mRNA vaccine

c. toxoid vaccine