ID E1- Respiratory Infections

What respiratory infection is caused by orthomyxovirus?

Influenza

How is influenza transmitted?

Aerosolized by cough/sneeze

The majority of flu-related deaths occur in what population?

Elderly

What type of influenza:

Most virulent, can cause pandemics

Influenza A

What type of influenza:

Major outbreaks result from antigenic shifts

Influenza A

What type of influenza:

Antigenic drifts are caused by point mutations

Influenza B

Which has more variation: Influenza A or Influenza B?

Influenza A

Antigenic drift or Antigenic shift:

Minor, gradual antigenic change due to accumulation of point mutations; creates viruses with slightly modified antigens; → Endemics

Antigenic drift

Antigenic drift or Antigenic shift:

Major change resulting in a new subtype; generates entirely novel antigens; → Epidemics

Antigenic shift

Antigenic drift or Antigenic shift:

One of the genes or RNA strands is substituted with a gene or strand from another influenza virus from a different animal host

Antigenic shift

Who should be vaccinated for influenza?

Everyone >6 months

What type of allergy requires the influenza vaccine to be administered in a hospital with supervision?

Egg (if severe rxn)

Is the flu shot safe to give to a pregnant patient?

Yes- protects mom & baby

Which influenza vaccine should pregnant women NOT get?

Flumist (live intranasal vax)

Flu or Cold:

Rapid onset, Severe malaise & myalgias, anorexia

Flu

Flu or Cold:

URI symptoms predominate

Cold

What is the most sensitive and specific test for diagnosing influenza?

RT-PCR (but takes 4 hours)

What Antiviral agent is used to treat influenza (A & B)?

Oseltamivir (Tamiflu)

What is the most common complication of influenza?

Secondary bacterial pneumonia

What pathogens usually cause secondary bacterial pneumonia as a complication of influenza?

Strep pneumo & Staph aureus

How is swine flu (H1N1) spread?

Person to person (not from pigs)

What type of PNA occurs in a patient in the community without extensive healthcare contact?

Community Acquired (CAP)

What type of PNA occurs in a non-hospitalized patient with extensive healthcare contact?

Health-Care Associated (HCAP)

What type of PNA occurs 48 hours or more after admission and did not appear to be incubating at the time of admission?

Hospital Acquired (HAP)

What type of PNA develops after more than 48 hours of mechanical ventilation?

Ventilator Associated (VAP)

What is the MCC of viral PNA in immunocompetent patients?

Influenza (2nd = RSV)

What is the treatment for viral PNA?

IV acyclovir

What pathogen is the MCC of CAP?

Strep pneumo

What is the pneumonia severity index (PSI) used for?

To determine need for hospital admission

PSI criteria: which risk classes can be treated outpatient?

I & II

PSI criteria: which risk classes should be treated in an observation unit/short hospitalization?

III

PSI criteria: which risk classes require hospitalization?

IV & V

CURB-65 criteria for PNA admission

Confusion

Urea (BUN): > 20 mg/dL

Respirations: ≥ 30 bpm

BP: systolic < 90 or diastolic ≤ 60

Age ≥ 65

Each criteria = 1 point

Key factors to identify Klebsiella PNA?

Blood-stained (currant jelly) sputum

What type of PNA is the 2nd MCC of CAP, and often associated with AOM?

Mycoplasma PNA

What type of PNA is most likely to cause hoarseness/laryngitis?

Chlamydia PNA

What type of PNA is spread via contact with psittacine birds, inhaled bird droppings, mouth-to-beak contact?

Chlamydia psittaci PNA (Psittacosis)

What PNA is associated with AC, showers, whirlpools, & contamination of cooling water systems?

Legionella PNA

What pathogen causes Pontiac fever?

Legionella pneumophila

When treating atypical CAP, what antibiotic should be used in a patient with comorbidities or recent abx use?

Levofloxacin

When treating atypical CAP, what antibiotic should be used in a patient with no comorbidities or recent abx use?

Z-Pak or Doxy

What is the tx for bronchitis?

NO Abx, self-limiting; sx relief, d/c smoking, bronchodilator & steroid

What pathogen causes pertussis (whooping cough)?

Bordetella pertussis

What are the 3 phases of pertussis (whooping cough)?

Catarrhal, Paroxysmal, Convalescent

S/S of pertussis (whooping cough)

Cough >2 weeks AND one of the following:

- Paroxysmal coughing

- Inspiratory whoop

- Post-tussive vomiting

What is the first line treatment for pertussis (whooping cough)?

Azithromycin

What immunization is given to infants for prevention of pertussis (whooping cough)?

DTaP & Tdap