禽流感-提高警惕-AVIANINFLUENZA.pdf

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AVIAN INFLUENA
The pandemic influenza clock is ticking. We just
don't know what time it is, ,>
laurene Mascoa MID MIPO FAAP
Acute Communicable Disease Control Program
DHS
D12: \Avian Flu, ppt No, 1
Acute Communicable Disease Control Proaram
OUTLINE
Background on Influenza A
Impact of influenza
Pandemics
Avian influenza A viruses
Human infections with avian
influenza A viruses since 1997
CH5N1 Asia 2005
CDC Tim Uyeki, MD
DHS
D12: \ vian Flu. ppt No, 2
Acute Communicable Disease Control Program
BACKGROUND
HUMAN INFLUENZA
Acute febrile respiratory illness
v Symptoms, signs may differ by age
Etiology: infection with human influenza
viruses (infect upper respiratory tract
epithelial cells
v 2 major surface glycoproteins
Hemagglutinin, Neuraminadase
8 gene segments code for 10 proteins
Types A and B viruses cause substantial
iliness and death among humans yearly
CDC TIM Ueki.Mp
DHS
D12: \Avian Flu. ppt No. 3
Acute Communicable Disease Control Program
EPIDEMIOLOGY
Short incubation period, usually 1-4 days
Spread by respiratory droplets-person-to
person, direct contact, rare aerosol
Highly contagious; infectious period
Adults: 1 day prior to symptoms thru 5 days post illness
v Children: >10 days
V Immune compromised shed virus for weeks to months
Virus 1st detectable iust before symptom onset
Usually not detectable after 5-10 days
DHS
D12: \ vian Flu. ppt No, 4
Acute Communicable Disease Control Program
KEY INFLUENZA VIRA
FEATURES
Surface proteins (major
antigens
.Hemagglutinin(HA
HA
v Site of attachment to host
cells
NA
v Antibody to HA is protective
> Neuraminadase (NA)
v Helps to release virions from
cells-oseltamavir works here
Antibody to NA can help
modify disease severity
CDC Tim Uveki MD
DHS
D12: \vian Flu. ppt No, 5
Acute Communicable Disease Control Program