most common causative agents of respiratory disease
DESCRIPTION
Most Common Causative Agents of Respiratory Disease URI Parainfluenza, adenovirus, influenza, rhinovirus Pharyngitis Adenovirus, parainfluenza, coxsackie Croup Parainfluenza, respiratory syncytial Bronchitis Parainfluenza, respiratory syncytial - PowerPoint PPT PresentationTRANSCRIPT
Most Common Causative Agents of Respiratory Disease
URI Parainfluenza, adenovirus, influenza, rhinovirus
Pharyngitis Adenovirus, parainfluenza, coxsackie
Croup Parainfluenza, respiratory syncytial
Bronchitis Parainfluenza, respiratory syncytial
Bronchiolitis Respiratory syncytial, parainfluenza
Pneumonia Respiratory syncytial, parainfluenza, adenovirus,influenza
Fry et al, CID 2006
The latest graph of virus activity in the Bay Area, asof November 19, as measured by identifications inthe UCSF Clinical Virology Laboratory, is attached;it can also be found at the following website:
http://labmed.ucsf.edu/images/graphs/viruses.gif
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Influenza A Virus Structure
Natural History of Influenza Viruses
Topley and Wilson’s Microbiology and Microbial Infections. 9th ed, Vol 1, Virology. Mahy and Collier, eds, 1998, Arnold, page 387, with permission.
1880 1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000
B
H3N2
H1N1
H2N2
H3N8
H2N?
H1N1
Serum antibody prevalenceVirus isolation
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Diagnostic Approaches for Influenza
Type of Test Indications for Use Lab Turnaround Time
Symptoms + epidemiology
“Classical symptoms” during influenza season -
Antigen-based rapid tests
Nonclassical symptoms, in season Classical symptoms, shoulder season (point of care)
<30 minutes
Direct fluorescent antibody (DFA) As antigen-based tests 0.5-3 hours
PCR When maximal sensitivity desired 6-24 hours
Culture Confirm antigen/DFA; obtain isolates for surveillance 24-48 hours
Ison, et al. Antiviral Res. 2002(55):227-278.
Positive Direct Fluorescent Antibody Test
Direct FA for Respiratory Viruses
Virus # Sens %Spec %PPV NPV
RSV 86 97 94 93
Flu A 86 99 97 99
Flu B 65 98 90 89
Para 1 52 100 100 99
Para 3 85 99 79 99
Respiratory PCR PanelInfluenza A - H3 N2
H1 N1 B
RSV A B
Para 1-4
AdenoMetapneumoRhinoEnteroCoronaSars
Covalciuc, et al.; J. Clin Micro 1999.
Weinstock and ZucottiJAMA, 2009
Antiviral Resistance in “Swine” Influenza H1N1
Adamantanes - Resistant
Oseltamivir - Susceptible (202/202, US, 3 resistant isolates outside US)
Zanamivir - Susceptible (including 3 oseltamivir resistant)
Recommended Rx - oseltamivir or zanamivir
Isolates tested (n)
Resistant Viruses,Number (%)
Isolates tested (n)
Resistant Viruses,
Number (%)
Oseltamivir Zanamivir Adamantanes
Influenza A (H1N1) 88 86 (98%) 0 (0) 88 0 (0%)
Influenza A (H3N2) 14 0 (0) 0 (0) 14 14 (100%)
Influenza B 40 0 (0) 0 (0) N/A* N/A*
*Data from CDC, last updated 1/3/09