Orthomyxo,Paramyxo,Picorna,Bunya,Toga,Reo,Arena

Question 1

Influenza A is in what viral family?

Answer 1

Orthomyxovirus

Question 2

What is antigenic drift?

Answer 2

Minor changes
-Point mutations in H&N genes

*Drift produces annual outbreaks and epidemics

Question 3

What is antigenic shift?

Answer 3

Major changes
-Genetic reassortment between strains

*Shift produces worldwide outbreaks (Pandemics) every 10-20 years

Question 4

What is the most common cause of death related to Influenza A?

Answer 4

Secondary bacterial pneumonia

Question 5

What are the Influenza A surface antigens?

Answer 5

• Hemagglutinin (H)

- Neuraminidase (N)

Question 6

What does Hemagglutinin bind to?

Answer 6

Sialic acid containing receptors on respiratory epithelial cells
-Expressed on infected cells (basis for the hemadsorption test)

Question 7

What viruses are Hemadsorption positive? (3)

Answer 7

• Influenza A&B
• Parainfluenza
• Mumps

Question 8

What is the current gold standard for diagnosis of Influenza A/B?

Answer 8

Culture

-being replaced by PCR

Question 9

Rapid antigen tests for influenza A/B (DFA) are capable of providing results in 30 minutes, what is the overall sensitivity?

Answer 9

50-80% sensitivity

-High specificity

Question 10

What is the most common causes of croup in children?

Answer 10

Parainfluenza 1

Question 11

What viruses are in the Paramyxovirus family? (5)

Answer 11

• Parainfluenza
• Measles (morbillivirus)
• Mumps
• RSV (pneumovirus)
• Human metapneumonvirus

Question 12

The morbillivirus causes what? (3)

Answer 12

• Classic measles
• Atypical measles
• Subacute Sclerosing Panencephalitis (SSPE)

Question 13

Classic Measles:

• Prodrome
• Rash
• Complications

Answer 13

• Cough, Coryza, Conjunctivitis (+/- Koplik spots)
• Descending rash (Head 1st)
• Otitis media, pneumonia, myocarditis

Question 14

Who is susceptible to Atypical Measles?

Answer 14

Teenage patients who received only 1 vaccination

Question 15

What is the risk of SSPE?

-Average incubation?

Answer 15

• 0.001%

- 7 years

Question 16

What does the Mumps virus cause? (5)

Answer 16

Parotitis, sometimes with:

-meningoencephalitis, orchitis, myocarditis, pancreatitis

Question 17

What is the most common cause of pneumonia & bronchiolitis in infants and toddlers?

Answer 17

RSV

Question 18

What is true regarding immunity to RSV?

Answer 18

Short lived

• recurrence throughout childhood is the rule
• Infections are progressively less severe

Question 19

How do you diagnose RSV in culture?

Answer 19

Formation of syncytia in Hep2 cells

Question 20

Human metapneumovirus is a significant cause of what?

Answer 20

Lower respiratory tract infections

*PCR preferred diagnostic modality

Question 21

Enterovirus and Rhinovirus are part of what viral family?

Answer 21

Picornaviruses

-small (pico) RNA (rna) viruses

Question 22

What viruses belong to the Enterovirus family? (4)

Answer 22

• Poliovirus
• Coxsackie A/B
• Enterovirus

Question 23

What does Poliovirus cause?

Answer 23

Poliomyelitis

-Destruction of spinal ventral horn motor neurons

Question 24

What does Coxsackie A virus cause?

Answer 24

• Herpangina (painful oral infection)

- Hand, Foot, and Mouth

Question 25

What does Coxsackie B virus cause?

Answer 25

- Grippe (epidemic pleuodynia) - Myocarditis - Pericarditis

Question 26

What does enterovirus cause?

Answer 26

Most common cause of viral meningitis (aseptic)

Question 27

What is the most common cause of the common cold?

Answer 27

Rhinovirus

Question 28

What does rhinovirus culture require?

Answer 28

Incubation at 32 degrees | -RT-PCR is preferred

Question 29

What viruses are part of the Bunyaviridae family? (4)

Answer 29

- Hantavirus - Bunyavirus - Nairovirus - Phlebovirus

Question 30

How is Hantavirus acquired and what does it cause?

Answer 30

- Aeroslized rodent shit | - Hantavirus pulmonary syndrome

Question 31

What does Bunyavirus cause?

Answer 31

California encephalitis

Question 32

What does Nairovirus cause?

Answer 32

Crimean Congo Hemorrhagic fever

Question 33

What does Phlebovirus cause?

Answer 33

Rift Valley Fever

Question 34

What viruses are part of the Togaviridae family? (3)

Answer 34

- Rubella - Alphavirus - Flaviviruses

Question 35

What does rubella virus cause?

Answer 35

German Measles | -Febrile illness with rash

Question 36

Rubella virus is generally benign but may have consequences in what circumstances? -What are the implications? (6)

Answer 36

Developing fetus with maternal infection (1st trimester) - Sensorineural deafness - Cataracts - Glaucoma - Micropthalmia - Congenital heart disease (PDA) - IUGR - Microcephaly

Question 37

What does Alphavirus cause?

Answer 37

Equine encephalitides

Question 38

What viruses are part of the Flavivirus family? (5)

Answer 38

- HepC - Dengue - Yellow Fever - St. louis encephalitis - West Nile virus

Question 39

Dengue and Yellow fever are most commonly transmitted via what?

Answer 39

Aedes mosquitos | A. aegypti or A. albopictus

Question 40

Yellow fever is viscerotropic for what organs? (4)

Answer 40

- Heart - Kidney - GI tract - Liver

Question 41

What is the most characteristic liver findings in Yellow Fever? (4)

Answer 41

- Midzonal necrosis - Councilman bodies - Microvesicular fatty metamorphosis - NO inflammation

Question 42

What is the most common cause of viral gastroenteritis?

Answer 42

Rotavirus (family Reoviridae)

Question 43

What are other common causes of viral gastroenteritis? (3)

Answer 43

- Calciviruses (Norwalk-like agent) - Adenoviruses (40&41) - Astrovirus

Question 44

What virus causes Lymphocytic Choriomeningitis?

Answer 44

Arenaviridae

Question 45

Arenaviridae virus: - Viral Particles - Transmission

Answer 45

- Virus particles contain host cell ribosomes, giving them a granular appearnce - Parasites of rodents that shed virus in their urine and feces -- Hamsters and House mice are the hosts to LCM virus