Viruses in Lung

Question 1

Respiratory Viruses:

Start with Respiratory transimission–> replication in upper tract and you can have what three complications?

Answer 1

Upper and sometimes lower respiratory infections and diseases

Respiratory disease; serious such as pneumonia

replication leads to viremia in target organs

Question 2

Influenza virus

_____subtypes of hemagglutinin (HA)

___ subtypes of neuraminidase (NA)

with both animal and human hosts playing key role in epidemiology

Answer 2

16

9

Question 3

Explain difference between antiginetic drift and shift in regards to influenza virus

Answer 3

Drift happens with slowly, over years, with small changes to HA or NA while NP stays constant

Shift happens rapidly (one year) with one big shift in NA or HA

Question 4

Flu Vaccine

1. Each year make vaccine to ___ strains
2. Post vaccine, body makes ____
3. If you are exposed to any of those strains, anitB latch onto virus’s _______ and prevent flu from attaching to healthy cells

Answer 4

3 strains (2 for A 1 for B)

body makes antibodies

latch onto virus’s HA antigens

Question 5

INfluenza virus genes are made of ____ making them more prone to mutations

If HA gene changes, so can the antiG that encodes it causing it to change shape… the antiB we got from flu vaccine no longer work, this is called

Answer 5

RNA

antigenic DRIFT

Question 6

The genetic change that enables flu strain to jump from one animal species to another including human:

Answer 6

anitgentic SHIFT

Question 7

W/out undergoing genetic change, a bird strain of influenza A can jump to another duck or even human, the new strain may further evolve and then can spread person to person… if so a flu _____ can arise

Answer 7

Pandemic

Question 8

How does genetic mixing result in a new strain of influenza

Answer 8

A bird can pass influenza A to pig

A person can pass influenza A to same pig

If both viruses infect the same cell and the genes mix–> get new strain

New strain can spread intermediate host to human

Question 9

The third way a bird host can get influenza to a human is if the influenza bird strain jumps to _____ and then to humans

Answer 9

human host

Question 10

Influenza ____ result from antigenic shift

Answer 10

pandemics

Question 11

H5N1 in 2014 was confirmed avian influenza that 393 people died from… is it easy to trasmit and how does it transmit?

What about H7N9?

Answer 11

does not transmit easily, people exposed to infected household poultry or contaminated environment

H7N9: doesn’t transmit easliy, killed 175

Question 12

Influenza pathogenesis:

what type of disease is it?

How does it infect host?

How is it replicated?

Answer 12

Influenza - acute respiratory diseaes

Virus infects ciliated epi cells lining URT, trachea and bronchi

Replicates by destruction of respiratory epithelium

Question 13

How does influenza cause cell damage?

Answer 13

From virus activation of cytotoxic T cells

***viremia doesn’t play major role in pathogenesis

Question 14

Describe tracheal mucosa:

normally-

3 days post infection

7 days post infection

Answer 14

Normally: ciliated

3 days post: all cilia gone (susceptible to 2nd bacterial infection) and decreased clearance of gunk

7 days post: slow regrowth of cilia

Question 15

Disease mechanism of A and B influenza viruses

1. Where it established infection
2. Cause of systemic symptoms and local symptoms
3. key for immune resolution

Answer 15

1. establishes infection in upper and lower RT
2. Systemic symptoms from interferon and cytokine response to virus

Local from epithelial cell damage: to ciliated and mucus secreating cells

3. •Interferon and cell-mediated immune responses (natural killer and T cells)

Question 16

Antibody for future protection against influenza is specific for ____ and ____

which can undergo major ______ or shift and minor _____ or drift

Answer 16

HA hemagglutinin and NA neuramidase

minor (mutution:drift) and major (reassortment: shift)

Question 17

Influenza B only undergoes what kind of changes?

Answer 17

minor antigenic changes

Question 18

Influenza is normally self limited, for 3-7 days and is more sever in ____ and ____

What is our major cause of death with influenza?

Answer 18

young and old

death from secondary bacterial infections: S.penumonaie, S.aureues, H.influenzae

Question 19

What rare complications can arise from influenza virus?

Answer 19

myositis and cardiac involvement
– Guillain-Barre’ syndrome
– encephalitis
– Reye syndrome

Question 20

What are our three vaccine options for influenza?

Answer 20

a. formalin inactivated - mixture of prevalent antigenic types (hemagglutinin and neuramindase)
b. attenuated infectious viruses → intranasal administration
c. quadrivalent vaccine available 2013

Question 21

Antiviral used to treat influenza that inhibits uncoating by blocking M2 protein

Answer 21

Amantadine adn imantadine (not used bc of high degree of antiviral resistance)

Question 22

Antivirals to tx influenza that are neuraminidase inhibitors (inhibit release of progeny virus):

Answer 22

Zanamivir and Oseltamivir (Tamiflu)

Question 23

Rhinovirus – key points
• Cause____% of common colds
• Antigenic diversity - _____ serotypes identified
RV-A (75 serotypes), RV-B (25 serotypes), RV-C (51 serotypes)
•_____ only natural host

Answer 23

50%

150

Humans

Question 24

Rhinovirus infections are _________ and temperature sensitive between ____ and ___ degrees

Answer 24

infections are mild and self limiting grow better at 33 degrees then 37

Question 25

How is Rhinovirus transmitted? How is rhinovirus prevented and controlled?

Answer 25

Transmission via respiratory secreations/ individual to individual and FOMITES PRevention and control: no antivirals no vaccines as of now, just handwashing and disinfectants (has the canyon floor pore)

Question 26

Resonsible for summer colds and flus: common cold symptoms, like fever, head ache and fatigue

Answer 26

Enterovirus

Question 27

Enterovirus has what two syndromes? what vaccine or antivirals are available?

Answer 27

Respiratory tract infection and undifferentiated fever no vaccine or antivirals available

Question 28

EV-D68 is enterovirus 68, seen this year in october... what are the symptoms of this disease?

Answer 28

Saw flaccid paralysis, not sure why, spread via respiratory secreations from human to human and inactivated by low pH thus doesn't replicate in GI tract

Question 29

What type of illness do we see do we see in Enterovirus D68?

Answer 29

mild to severe respiratory illness, severe; difficulty breathing and wheezing particullarly bad in asthmatics.

Question 30

Corona viruses causes what? What symptoms do we see? Is there a vaccine available?

Answer 30

cause common colds (second most prevalent cause representing 10 -15% of total) - watery eyes, sneezing, nasal congestion, sore throat, sometimes fever, chills, headache, other aches, cough • no vaccine available

Question 31

Where in the body does Coronavirus infect?

Answer 31

• disease limited to upper respiratory tract, infects epithelial cells (optimal temperature for viral growth is 33° to 35°)

Question 32

Sudden Acute Respiratory Syndrome- what kind of virus? • Fatality rate among people with illness - about \_\_\_\_ • Transmission mainly by:

Answer 32

Coronavirus 10% f_ace-to-face_ contact , virus in respiratory secretions and feces, **not highly contagious **

Question 33

How was SARs controlled? What was the source? What tx/vaccines are available?

Answer 33

By containment source = bats No vaccines or antivirals available

Question 34

MERS is what type of virus? What besides humans does it infect? How is it transmitted?

Answer 34

Coronavirus infects bats and camels Doesn't pass human to human easily, it's an RNA virus thus unstable

Question 35

What symptoms/ disease results from MERS?

Answer 35

Disease: acute severe pnemonaie and renal failure~ people in serious cases tend to have underlying medical issues\* \*\*nosocimial documented

Question 36

Nosociomial transmission of MERS (not sure how important this is below, just be aware)

Answer 36

Patient 1 visited Dubai in April 2013, Patient 2 lives in France and did not travel abroad. Both patients had underlying immunosuppressive disorders. Initial clinical presentation included fever, chills, and myalgia in both patients and diarrhea in Patient 1. Respiratory symptoms rapidly became predominant with acute respiratory failure leading to mechanical ventilation. Both patients developed acute renal failure. MERS-CoV was detected in the lower respiratory tract specimens with high viral loads. The two patients shared the same room and bathroom in the hospital for 3 days. The incubation period was estimated at 9-12 days for the second case. No secondary transmission was documented in the hospital staff despite the absence of specific protective measure before the diagnosis of MERS-CoV was suspected. Patient 1 died on May 28 due to refractory multiple organ failure. Patient 2 recovered and was discharged from the hospital.

Question 37

When do we see parainfluenza? What group is at risk? Vaccine available?

Answer 37

occurs in fall and winter, common nosocimial infection See complications from parainfluenza in infants and young children (CROUP) No vaccine

Question 38

This virus cause lower respiratory complications in infants and young children such as Croup = subglotal , fever, hoarse voice, loss of apetite, barking cough adn stridor on inhilation

Answer 38

Parainfluenza

Question 39

Type I and 2 parainfluenza are common causes of : Type 3 is simular to: Type 4 is:

Answer 39

1 and 2 like croup 3 simular to RSV 4 mild

Question 40

Respiratory syncytial virus – key points Where is the infection located? What problem can it cause in infants? When are most people infected with this?

Answer 40

Localized infection of respiratory tract, no systemic spread Blockage of narrow airways of infants Infects virtually everyone by age 2

Question 41

How does Respiratory Syncytial virus cause blockage of airways in infants?

Answer 41

Blockage of narrow airways of infants ◊ Virus-induced CPE includes syncytia (multinucleated cells) ◊ Induction of inflammatory cytokines

Question 42

ONce you are infected with RSV, will you get it again?

Answer 42

Natural infections do not prevent re-infection ◊ Infections throughout life, can be severe in the elderly ◊ Presents vaccine challenges

Question 43

Clinical consequences of RSV in Chilren under one: Children: older children/adults:

Answer 43

Children under 1: bronchiolitis, penumonia or both w/ fever, cough, dysnpnea and cyanosis Children: febrile rhinitis and pharnygitis Older: common cold

Question 44

Tx of RSV in otherwise health infant: premmaure/immunocompromised infants: Premature:

Answer 44

* Otherwise healthy infant – treatment i**s supportive**, oxygen, IV fluids, nebulized cold steam * Premature or immunocompromised infants - **aerosolized ribavirin** * Premature infants – **passive immunization with anti-RSV Ig and humanized monoclonal antibodies**

Question 45

Metapneumovirus is simular to what disease and in what pt population? By what age are children seropositive for Metapneumovirus and how is it identified? Vaccine?

Answer 45

disease similar to RSV but in general milder, with the most severe disease seen in infants, the elderly, and immunocompromised By 5 most kids have it, identified by RT-PCR No vaccine available

Question 46

• Two emerging respiratory viruses with high mortality rates • Have made the apparent jump from bats to people with pigs as an intermediate host in Australia and Asia.

Answer 46

Hendra and Nipah virus

Question 47

``` Causes a wide spectrum of disease: respiratory infection (pharyngitis), conjunctivitis (pink eye), gastrointestinal infections, hemorrhagic cystitis (inflammation of the urinary bladder) ```

Answer 47

Adenovirus

Question 48

Adenovirus disease is determined by: When do we see systemic infection of adenovirus

Answer 48

determined by the tissue tropism of the specific group or serotype of the virus (\>50 serotypes of adenovirus) See systemic infection in immunocompromised patients

Question 49

What prevention and control is available for adenovirus?

Answer 49

o No adenovirus vaccine available for general public, new live attenutated vaccine against adenovirus types 4 and 7 was approved by the FDA in 2011 for **military recruits** o **Cidofovir** has been used to treat s_evere adenovirus_ in immunocompromised people

Question 50

Pharyngoconjuctival fever (red eyes, sore throat adn fever in young kid) athlete with flu like symptoms, vomitting, chills and high fever--\> progressing to pneumonia febrile respiratory illness on Naval base What do all of these have in common?

Answer 50

Cuased by adenovirus

Question 51

Measles virus is characterized by what symptoms? What's the most common cause of death in young children with measles?

Answer 51

cough, conjunctivitis, coryza, with otitis media, croup, pneumonia Pneumonia

Question 52

Adenovirus is in 1. Which virus family? 2. DNA or RNA? 3. Naked or enveloped?

Answer 52

Adenovirdiae DNA and Naked

Question 53

Rhinovirus and enterovirus are both \_\_\_\_\_\_ They are DNA or RNA Naked or Enveloped

Answer 53

Rhino and Entero are both Pircornavirus They are +RNA and Naked

Question 54

SARs, MERS are both Coronavirus, which is DNA/RNA Enveloped/Naked

Answer 54

Coronavirus are +RNA and Enveloped

Question 55

What virus family does Influenza belong in? DNA or RNA Enveloped or Naked?

Answer 55

Inlfuenza is in Orthomyoviridae -RNA and is Enveloped

Question 56

Parainfluenza, RSV, Metapneumovirus and Measles are all in what virus famaily? They are DNA or RNA Naked or Enveloped

Answer 56

Parainfluenza/RSV/metapneumovirus/Measles =Paramyxoviridae famiy (-)RNA and is Enveloped