L10 Respiratory Tract Infections: Influenza and Chlamydia Flashcards
Causes of ARD
Rhinoviruses (25%)
Coranoviruses (10%)
Adenoviruses + unknown viruses (30-40%)
Rhinovirus season
endemic and winter
Relationship between cold weather and URI
NO direct causation
Rhinoviruses transmission
Aerosol
person-to-person by HANDS
Fomites: stable, persist in environment
carrier state likely
rhinovirus immunity
transient, 18 months
Acute flaccid myelitis
weakness/paralysis similar to poliovirus
cases started in 2014, mostly children
viral etiology suspected
Acute flaccid myelitis symptoms
difficulty moving eyes drooping eyelids facial droop/weakness difficultly swallowing slurred speech sudden arm/leg weakness
Species of influenza and what defines them
A B C
Their nucleocapsid proteins
Influenza A
the worst influenza
Influenza B
also causes epidemics
Influenza C
weak strain
Antigenic subtypes of influenza are defined by
envelope proteins
large numbers are known
Hemagglutinin
H antigen
Viral attachment
Neuraminidase
N antigen
Viral penetration and release from infected cells
How is an influenza virus named
Type/Location of Discovery/Year/Antigenic type
Ex: A/Spanish/18/HswN1`
influenza incubation
SHORT
1-2 days
very abrupt onset of sx
influenza symptoms
fever
aches
chills
cough
influenza duration
illness for 1 week with long convalescence
Complications of Infuenza
Pneumonias (primary, or secondary bacterial)
Reyes syndrome
Guillain barre syndrome
causes of secondary bacterial pneumonia from influenza
Streptococcus pneumoniae
Staphylococcus aureus
Haemophilus influenzae type B (Hib)
Reyes syndrome
associated with many viral infections
influenza A/B or chickenpox in peds patients on long term ASA therapy
edematous encephalitis + fatty alteration of liver
Guillain Barre syndrome
demyelination that sometimes (40%) results from a viral infection, otherwise cause unknown
Recent cause of Guillain Barre syndrome
1976 swine flu vaccine
influenza rapid antigen tests problems
false negatives early in the course of the disease due to low antigen levels
when to vaccinate against the flu
october, before the typical flu season begins
Flu vaccines are
multivalent