INFECTIOUS DISEASESELECTED VIRUSESA 60-year-old male with a history of COPD presents with 12 hours of flulike
symptoms in the middle of a known outbreak of influenza. What antiviral
agent is contraindicated in this patient?
Zanamivir (because of COPD history).Influenza
■ A single-stranded RNA, orthomyxoviridae virus
■ Types: A (pandemic; tends to be more pathogenic), B (epidemic), and
C (sporadic)
■ Spread by droplets (highly contagious)
■ Maximal transmission November–April (Western hemisphere)
SYMPTOMS/EXAM
■ Incubation period: ~2 days
■ Characterized by:
■ Sudden onset, high fever (2–4 days)
■ Headache
■ Nonproductive cough
■ Myalgias
■ Sore throat
■ Fatigue and malaise (can last weeks)
■ Children frequently note GI symptoms.
DIFFERENTIAL
Bacteremia, parainfluenza, RSV, adenoviruses, coronaviruses, echoviruses
DIAGNOSIS
■ Clinical (during known outbreak ~85% accurate)
■ Rapid antigen test
TREATMENT
■ See Table 8.1.
■ Antivirals:
■ Treatment (only if symptom duration <48 hours)
■ Prevention (if exposed during known outbreak)
COMPLICATIONS
■ 1 °(viral) and (bacterial) 2°pneumonia
■ Occur most frequently in the elderly and those with comorbidities
■ Rare: Aseptic meningitis, pericarditis, Guillain-Barré
Mononucleosis
■ Epstein-Barr virus (EBV)
■ Transmitted by saliva (ie, the “kissing” disease)
■ >90% of population has developed antibodies to EBV
All antivirals for influenza are
only efficacious if started
within 48 hours of symptoms.