Molecular Diagnostics Practice Exam 1

What is the most common congenital infection in the United States?

What is the most common congenital infection in the United States?

CMV

What is the most common strain of Hantavirus in the U.S.?

Sin Nombre

What family of viruses causes Zika and West Nile?

Flaviviridae

HIV primarily targets CD__ cells.

CD4+

This type of Hepatitis is a defective RNA virus-like pathogen that is transferred mainly by parenteral route.

Hep D

DNA is tightly compressed around ___ to save space.

Histone proteins

Bases with a single ring structure are called ____ and contain ___ and ___.

Pyrimidines
Thymine and Cytosine

A virus envelope is comprised of a ______

phospholipid bilayer

The first __ days of a viral infection are considered the acute phase.

5

Serologic assays detect ____ to viruses.

circulating Ab

In a serologic assay, antibody levels do not correlate with ____.

Level of infection

What is the gold standard of viral isolation?

cell culture

One costly but sensitive method of virus detection is ____;

Nucleic Acid Based Detection

What are the 4 families of double stranded DNA viruses?

-Adenoviridae
-Herpesviridae
-Papillomaviridae
-Poxviridae

Family of naked ds-DNA viruses that are very stable outside the body

Adenoviridae

Family of viruses that are associated with the military, viral pink eye, and inadequately chlorinated pools.

Adenoviridae

What does family Adenoviridae look like in a cell culture?

Swollen grape-like clusters

What are the 8 species of Herpesviridae?

-Herpes Simplex viruses (HSV-1 and HSV-2)
-Varicella-Zoster virus (VZV)
-Epstein-Barr virus (EBV)
-Cytomegalovirus (CMV)
-Human Herpesvirus 6 (HHV-6)
-Human Herpesvirus 7 (HHV-7)
-Human Herpesvirus 8 (HHV-8)

Infections with ____ double the risk of HIV.

Genital Herpes

What is the mortality rate for neonatal herpes?

About 60%

HSV encephalitis has a ____ mortality rate and is usually caused by ____ in neonates.

High (70%) HSV-2

How is HSV-1 ad HSV-2 diagnosed in the lab?

Immunofluorescence of specimens from lesions.

What are the 2 manifestations of Varicella?

Chicken Pox and Shingles

What does EBV cause?

Infectious mononucleosis

What virus is Hodgkin lymphoma associated with?

EBV

What viral family is comprised of the smallest ss-DNA viruses?

Parvoviridae

What virus is associated with a "slapped cheek" appearance?

Parvovirus B19

A fever occurs __-__ days before a rash occurs with Smallpox whereas fever occurs ___ with Chicken Pox.

2-4 at the time of rash

Chicken Pox affects the ___ area of the body whereas Smallpox affects the ___ of the body first.

Trunk
Limbs

With Smallpox the rash is in the ____ stage(s).

Same

With Chicken Pox the rash occurs in ___ stage(s).

Different

Development of the Smallpox rash is ___and development of the Chicken Pox rash is ____.

Slow
Fast

In otherwise healthy patients ____ results in a transient anemia.

Parvo B19

Parvovirus B19 causes transient aplastic crisis in patients with ____.

Sickle Cell

What virus causes Smallpox?

Variola

What family are largest of all clinically significant viruses part of?

Poxviridae

What type of cells are abnormal in patients with HPV?

Koilocytes

This virus is similar to HHV-6 with infection occurring later in childhood.

HHV-7

This virus is associated with Kaposi sarcoma and causes patches of abnormal tissue.

HHV-8

This naked virus has a wheel-like appearance.

Rotavirus

What are prions?

proteinaceous infectious particles (not viruses)

This type of Hepatitis infected the blood supply and causes cirrhosis in 30% of those infected.

Hep C

What are the 3 phases of translation? Where does this occur?

Initiation
Elongation
Termination
Occurs in the Cytoplasm

_____fragments are on the lagging strand during DNA replication.

Okazaki

The genome of Parvovirus B19 is comprised of_____

SSDNA

What are 5 risks for the recurrence of a herpes family virus?

-Sunburn
-Systematic infection
-Immune impairment
-Stress
-Menstruation

Cells have a distinctive ____appearance in a Tzanck smear.

giant and multinucleated

What is the shape of the Herpes family viruses? Do they have an envelope?

Icosahedral
No envelope

The ___ is a part of the body commonly involved in genital Herpes.

Urethra

Genital Herpes is usually caused by HSV-___.

HSV-2

____ is the most common cause of corneal infection in the United States.

Ocular Herpes

CMV replicates only in ___ cells.

Human

CMV is life threatening in a ______ host.

Immunocompromised

CMV can cause ____ in a fetus.

Microcephaly

95% of young adults are seropositive for this type of Herpes. It is known as the "sixth disease".

HHV-6

This type of Herpes causes seizures in 30-40% of children.

HHV-6

This is the only double stranded RNA virus that is medically important.

Rotavirus

This virus is spread by the deer mouse and has a 50% mortality rate.

Hantavirus

Hantavirus is a ___ stranded ___ virus.

Single
RNA

This virus is commonly found on cruise ships.

Norovirus/Norwalk

The Norwalk virus gives you ___ term immunity.

Short-term

This type of virus was responsible for the SARS and MERS outbreak.

Coronavirus

This helical virus usually infects only one species of animal.

Coronavirus

What is the reservoir of filoviruses?

Bats

What are the 2 types of filoviruses?

Marburgvirus and Ebolavirus

What are some unique symptoms of filoviruses?

Bleeding from the gums or nose; internal organ hemorrhage

Name at least 2 Arboviruses.

Zika
West Nile
Dengue virus
Yellow Fever
St. Louis encephalitis

Known as "breakbone fever".

Dengue virus

Dengue hemorrhagic fever occurs if ___.

patient infected with a different serotype

What is the most common flaviviridae virus in the United States?

St. Louis Encephalitis

Humans are dead end hosts for this virus.

West Nile

What virus is associated with Guillian-Barre Syndrome?

Zika

What family of viruses does Influenza belong to?

Orthomyxoviridae

This virus causes a fever that can get up to 106 degrees and possibly fatal pneumonia.

Influenza A

The flu shot is made of a(n)____ virus.

Inactivated

There are __ different Influenza A strains and __ Influenza B strain.

2
1

What is the difference between antigenic drift and antigenic shift?

Drift occurs slowly and shift occurs at a rapid pace.

What family of viruses does Measles and Mumps belong to?

Paramyxoviridae

Causes "barking cough" and is common in children.

Croup

Causes "Koplik spots".

Measles

Measles reproduces in the ___tract and is known as ____.

Respiratory
Rubeola

This is a small naked viruses that resist detergents and temperature extremes.

Rhinovirus

What type of nucleic acid do retroviruses have? Are they enveloped?

ss-RNA
YES

What is HAART? What virus is it associated with?

Highly Active AntiRetroviral Therapy used to combat HIV

A retrovirus is an RNA virus that has its own _____.

Reverse transcriptase

The ____ virus causes infection of the parotid glands.

Mumps

What is the most common cause of severe LOWER respiratory tract disease?

RSV

Forms syncytia in lungs and in culture.

RSV

Enteroviruses are more prevalent in ____ countries.

Poverty stricken

This virus is associated with hand foot, and mouth disease (HFMD).

Coxsackievirus

Causes rubella or German measles and halts cell growth.

Rubivirus

Poliovirus and Coxsackievirus are examples of _____.

Enteroviruses

This virus initially infects the GI tract and then moves to the nervous system, where the neurons are never replaced.

Polio

What are the 2 vaccines used for Polio?

Salk and Sabin vaccines

Where are skin biopsies taken from a patient infected with Rabies?

Back of the neck

What do you look for in a deceased patient infected with Rabies?

Negri Bodies

Only 3 people in the United States have survived this virus without prophylactic treatment.

Rabies

What type of HIV is responsible for the worldwide pandemic?

HIV-1

67% of HIV cases take place in _______.

Subsaharan Africa

What are the 5 opportunistic infections associated with AIDS?

Candidiasis of mouth and respiratory tract
Fungal meningitis
Kaposi sarcoma
Recurrent pneumonia
Wasting syndrome