Influenza & RSV Flashcards
There are 3 types of influenza viruses. What causes most human infections? What surface proteins do they contain?
Influenza type A
Contain Hemagglutinin (H) and Neuraminidase (N)
Function of H and N
H binds to respiratory epithelia cells
N cleaves the bond that holds newly replicated virions to cell surface, allowing it to spread
Why does the flu shot constantly have to change?
HINT: What is unique about viral RNA polymerase?
Viral RNA polymerase lacks error-checking and so there is an antigenic drift/shift from year to year
Presentation of the flu
Abrupt onset Fever 100-104 Sore throat 3-5 days Headache Ptosis (droopy eyes) Myalgia
What are some influenza complications and who is at high risk for these?
Secondary bacterial pneumonia
Myositis
Myocarditis and pericarditis
Women in 3rd trimester, elderly, CV disease patient’s are at highest risk
How would you diagnose the flu?
Can go off hx and presentation
PCR tests are the most sensitive
Rapid diagnostic tests are costly and not very specific
What are antiviral drugs used to treat the flu
Oseltamivir and zanamivir
What is the definition of bronchiolitis?
Lower airway viral infection in children < 2 years old
What is the most common cause of bronchiolitis?
RSV
What does the presentation of bronchiolitis look like?
Fever Rhinorrhea Cough Poor feeding Don't sleep Wheezing Tachycardia
How do you treat bronchiolitis?
Observation
Supplemental O2
Parenteral fluids
Debatable bronchodilators and corticosteroids
Respiratory Syncytial Virus (RSV) presentation:
Profuse watery/frothy white nasal discharge
Fever, cough, tachypnea, cyanosis, retractions, wheezing, rales
Apneic episodes in very young children
What are risk factors for RSV?
Premature
Heart or lung dz
Young age
Increased interleukin levels
How do you treat RSV?
Supportive care is mainstay
Bronchodilators, epinephrine racemic,
Ribavirin and Palivizumab
Is there a vaccine available for RSV?
No
