IDBR - Respiratory Viral infections

Question 1

Describe the types of Influenza virus?

Answer 1

Flu A, B, C. Flu A: 16 HA types, 9N types, responsible for seasonal drift. Huge reservoir in fowl Causes disease in poultry Point Mutations in neuraminidase lead to resistance to NAIs

Question 2

Minor complications of Influenza?

Answer 2

1. Croup
2. Bronchiolitis
3. Asthma exacerbation
4. OM
5. Sinusitis/parotitis

Question 3

Groups at risk for complications of Influenza?

Answer 3

Question 4

45 y/o with CC: fever, diarrhea, myalgia, sore throat, and dyspnea. Hypotensive and hypoxemic. CBC shows mild leukopenia, everything else normal. 3 days prior he was inspecting poultry operations in Jiangsu, China.

1. H1N1?
2. H3N2
3. H5N1
4. H7N9?
5. Influenza B?

Answer 4

H7N9

Question 5

Name the influenza A viruses that infects human

Answer 5

Question 6

Basics of H7N9?

Answer 6

• Avian to human transmission
• some intrinsic and some emergent oseltamivir resistance
• 22% case fatality

Question 7

basics of seasonal influenza transmission?

Answer 7

Question 8

5 days ago (january), healthy 25 year old female developed fever, myalgia, sore throat, and malaise, dx with influenza with slow improvement. 16 hours ago, she becomes hypotensive, diarrhea, abdominal pain, with a diffuse erythematous rash.

On exam, slow to respond, diffuse, rales, mild non-focal abdominal tenderness. CXR diffuse infiltrates, WBC 5500 (60% poly,30% bands). Platelets 40K, creatinine 1.9, AST and ALT 2x normal, with normal ammonia level. Erythoderma on exam.

What is the most likely cause of this influenza complication?

1. Reyes syndrome
2. Staph aureus pneumonia with TSS
3. GN sepsis with ARDS
4. Pneumococcal meningitis
5. Viral encephalitis

Answer 8

Staph Aureus with Toxic Shock Syndrome

Question 9

what are the severe complications of influenza?

Answer 9

Question 10

18 yo HS student with F/C/cough, myalgia in January. Given azithromycin, rest, NSAIDs, but fever, cough, continue becomes progressively dyspneic and weak. T39, P150, RR24-30, BP 120/50. Crackles throughout base and an S3 gallop. Influenza PCR positive. WBC 9K, creatinine 1.9, BNP high, CXR shows diffuse b/l infiltrates and cardiomegaly. Requires V-A ECMO.

What is the most likely cause of this influenza complication?

1. pneumococcal PNA
2. Staph aureus pneumonia w/purulent pericarditis
3. Influenza cardiomyopathy
4. MIS-C due to recent COVID infection
5. Viral pericarditis with effusion
6. PE due to hypercoaguable state

Answer 10

influenza cardiomyopathy

Question 11

what are the non-respiratory complications of influenza?

Answer 11

Question 12

20 year old woman s/p 18 days from HSCT in january, engrafted 3 days ago. Develops fever, hypoxemia, b/l lung infiltrates, and requires intubation. Nasal swab is negative by rapid test for influenza. Which of the following is the next best action?

1. Do not initiate anti-influenza therapy due to rapid test. The timing suggests idiopathic pulmonary syndrome (engraftment)
2. Initiate anti-influenza therapy empirically and send tracheal aspirate/BAL for influenza PCR?
3. Send IgG and IgM for influenza
4. Send RSV EIA and initiate empiric IV ribavirin

Answer 12

initiate anti-influenza therapy empirically and send tracheal aspirate or BAL for influenza PCR

Question 13

how do you make the diagnosis of influenza? serology?

Answer 13

clinical dx as good as rapid PCR in high peak seasons!

Question 14

influenza in transplant patients pearls?

Answer 14

Question 15

32 y/o nurse, 34 weeks pregnant, during influenza season. Gets symptoms, seen at urgent care where rapid test positive, and given Azithromycin. 72 hours later, gets fever, tachypnea, decreased UO with CXR showing bl hazy infiltrates. She’s hospitalized.

what is the correct statement?

1. she should get supportive care only since >48 hours
2. Oseltamivir is relatively CI in pregnancy
3. Zanamaivr is clearly preferred b/c of low systemic absorption
4. Oseltamivir should be started ASAP

Answer 15

Oseltamavir should be started ASAP

Question 16

what are the recommended medications for influenza treatment? prophylaxis?

Answer 16

1. oseltamivir, zanamivir, baloxavir
2. Empiric treatment for pregnant women and up to 2 weeks postpartum
3. duration 5 days
4. initiating tx within 2 days of symptoms results in M&M reduction
5. Pregnancy should not be CI to oral oseltamivir or zanamivir use

Question 17

Basics of baloxavir?

Answer 17

• cap -dependent polymerase inhibitor
• non-inferior to oseltamivir in 2 phase 3 studies
• superior for influenza b in patients with risk factors
• shorter duration of shedding
• resistance mutations emerge on tx in 10-20% of patients.

Question 18

basics of antiviral prophylaxis?

Answer 18

Question 19

Influenza Anti-viral pearls?

Answer 19

Zanamivir

Question 20

ACIP recommends routine influenza vaccinations for? what type?

Answer 20

• all persons aged 6 months or older
• QIIV (quadrivalent Inactivated influenza vaccine) - H1N1, H3N2, B yamagata, B Victoria

Question 21

vaccine pearls to tell patients?

Answer 21

• efficacy varies by year and group
• generally 50-70%, lower in special pop
• In HIV patients, response related to CD4 count
• Major mismatch occurs at least every 10 years.
• Can be given in patients with egg allergies
• Recombinant influenza vaccine (RIV, FluBloc) is available and contains no egg protein
• Consultation with allergist to egg no longer recommended
• Anaphylaxis to flu vaccine is still a CI.
  *

Question 22

describe the newer flu vaccines?

Answer 22

Question 23

In patients hospitalized with CAP, what is the top 3 viral pathogens in >65 years old.

Answer 23

1. Human rhinovirus
2. influenza A or B
3. Strep pneumo

Question 24

what findings suggest viral vs bacterial CAP?

Answer 24

Question 25

What are the respiratory viruses in HSC transplant patients to watch out for? Tx?

Answer 25

Question 26

18 year old presents in march in portland OR in congregate facilitywith several days of fever, cough, chest pain, tachypnea hypoxia, and conjunctivitis with WBC 3.0, platelets 160, CRP 2.5, AST 75. 2 days later, in the ICU. You suspect? 1. Pneumococcal PNA 2. borrelia hermsii with ARDS 3. Adenovirus 4. Hantavirus pulmonary syndrome 5. MRSA pneumonia 6. Group A strep with TSS

Answer 26

* Adenovirus. * Pneumococcal - can't explain conjunctivitis * Hantavirus - no exposure * no MRSA -absence of effusion * no TSS

Question 27

basics of Adenovirus?

Answer 27

Question 28

basics of adenovirus in transplant patients?

Answer 28

Question 29

71 y/o M w/COPD MI admitted in January for progressive dyspnea, cough, tachypnea, low grade fever, rhinitis. Spending more time with young child who has bronchiolitis. CXR shows bilateral perihilar infiltrates c/w pna. The recommended strategy pending lab results regarding isolation should be: 1. put him in a regular 2 bedded room with standard precautions 2. Put him in a single room with standard precautions 3. put him in a single room with contact/droplet precautions 4. put him in an airborne isolation room with airborne isolation

Answer 29

Put him in a single room with contact/droplet precautions

Question 30

Multiplex PCR of nasal swab shows RSV, patient has CXR showing bilateral infiltrates. Which of the following is correct? 1. RSV is an incidental finding which may cause URI symptoms 2. RSV likely accounts for an infiltrate. He should be immediately started on palivizumab (synagis) and ribavirin. 3. RSV likely accounts for infiltrate. Support care is appropriate 4. He has a high risk of CAP and should be started on vanc/zosyn.

Answer 30

RSV likely accounts for infiltrate. Supportive care is appropriate.

Question 31

basics of RMSV, hMPV in older adults?

Answer 31

Question 32

basics of RSV?

Answer 32

* Incubation period 2-8 days * Diagnosed by PCR * No indication for palivizumab * inhaled ribavarin controversial * Oral ribavarin appears equally effective.

Question 33

basics of human metapneumovirus?

Answer 33

Question 34

basics of parainfluenza virus?

Answer 34

Question 35

basics of MERs - coronavirus?

Answer 35

Question 36

35 y/o man admitted to the ICU in july with fever, dyspnea, hypotension. 5 days PTA c/o flu. Recently camped in yosemite national park which has rodent infestation issues. Has a parakeet, dogs, kittens, owns a hot tube. 2 kids in daycare have a URI. Labs HCT 52, WBC 6.0 (20% bands, 45% poly,s 2+ atypical lymphs), platelets 90K AST 105, PT 18, PTT 25, CXR shows bilteral infiltrates leading to white out. which of the following is mostly likely cause? 1. Adenovirus 2. influenza 3. anthrax 4. coxiella burnetii 5. hantavirus pulmonary syndrome

Answer 36

answer is hantavirus.

Question 37

basics of hantavirus pulmonary syndrome?

Answer 37

Question 38

what are the stages of hantvavirus pulmonary syndrome?

Answer 38

Question 39

what are the critical clues to hantapulmonary syndrome?

Answer 39

pneumonia with ARDS +