Transcript Avian Influenza in Humans-2004

Avian flu?
In humans?
Avian Influenza in Humans2004
Silvio Pitlik, MD
Mar 17, 2004
Avian Influenza in Humans2004
Silvio Pitlik, MD
Mar 17, 2004
Outline
– How Mother Nature ignites emerging
infections
– Historical perspective
– Clinician’s perspective
– Back to the future
Influenza Virus
•
•
•
•
Highly unstable
Sloppy
Promiscuous
Completely unpredictable
Dr Anarfi Asamoa-Baah, Assistant Director-General,
WHO Communicable Diseases
Opening address-Technical consultation on
influenza pandemic preparedness- March 16, 2004
one small step for man,
one giant leap for mankind
Neil Armstrong
Crossing the species barrier —
one small step to man,
one giant leap to mankind
NEJM, Mar 18, 2004
Emerging Infections-1990’s
•
•
•
•
•
•
•
•
•
•
•
•
•
Andes virus
Banna virus
Bartonella henselae
Bayou virus
Cycloscopora cayetanensis
Ehrlichia chaffeensis
Ehrlichia equi
Equine morbillivirus
Fakeeh virus
Guanarito virus
Hendra virus
Hepatitis G virus
HIV-1
•
Picobirnavirus
•
•
•
•
•
•
•
•
•
•
•
•
•
Influenza A H5N1
Influenza A H9N2
Juquitiba virus
Laguna Negra virus
Lechiguanas virus
New York virus
Nipah virus
Oran virus
Oscar virus
Prion protein
Rotavirus 116E P360
Sabia virus
Sin nombre virus
Current Opinion in ID, 2000
How Mother Nature Ignites an
Emerging Infection
How Mother Nature Ignites an
Emerging Infection
Wild-life
reservoir
How Mother Nature Ignites an
Emerging Infection
Wild-life
reservoir
Man-made
amplifier
How Mother Nature Ignites an
Emerging Infection
Disease
Wild-life
reservoir
Man-made
amplifier
AIDS
Pan troglodites
troglodites
Promiscuous sex, drug
adiction, blood products
SARS
Paguma larvata
Restaurants, hotels,
hospitals
WNV
Wild birds
Geese farms
Monkeypox
Wild rodents in Africa
Pet retailers and stores
How Mother Nature Ignites an
Emerging Infection
Disease
Wild-life
reservoir
Man-made
amplifier
AIDS
Pan troglodites
troglodites
Promiscuous sex, drug
adiction, blood products
SARS
Paguma larvata
Restaurants, hotels,
hospitals
WNV
Wild birds
Geese farms
Monkeypox
Wild rodents in Africa
Pet retailers and stores
Influenza
Wild aquatic birds
Poultry farms
Healthy
aquatic
birds
Natural hosts of influenza viruses
Haemagglutinin subtype
H1
H2
H3
H4
H5
H6
H7
H8
H9
H10
H11
H12
H13
H14
H15
Neuraminidase subtype
N1
N2
N3
N4
N5
N6
N7
N8
N9
Bird-flu in humans
Year
Place
1997
Hong Kong
H5N1
18
6
0.33
1999
Hong Kong
H9N2
2
0
0.00
2003
Hong Kong
H5N1
2
1
0.50
2003
Netherlands
H7N7
84
1
0.01
2003
Hong Kong
H9N2
1
0
0.00
2004
Viet Nam
H5N1
22
15
0.68
2004
Thailand
H5N1
11
7
0.64
140
30
0.21
Total
Strain # of cases # of deaths Case fatality
Outbreak of influenza A (H5N1) in
Hong Kong in 1997
Age and sex distribution of patients
infected with influenza A (H5N1)
Geographical distribution of influenza A
(H5N1) infected cases in Hong Kong
Diagnostic algorithm for the rapid
diagnosis of H5N1 infection.
Avian influenza A virus (H7N7) associated with human
conjunctivitis and a fatal case of ARDS- Netherlands 2003
•
•
•
•
•
•
Overall - 89 patients
78 - conjunctivitis
5 - conjunctivitis and influenza-like illness
2 - influenza-like illness
4 - did not fit the case definitions
Illnesses were generally mild, except for a
fatal case of pneumonia in combination
with ARDS
Sick
chicken
Dead
chicken
Radiological Findings
Prerequisites for the Start of a
Pandemic
• First, a novel virus must emerge to which the
general population will have no or little immunity
• Second, the new virus must be able to replicate
in humans and cause disease
• Third, the new virus must be efficiently
transmitted from one human to another. Efficient
transmission is expressed as sustained chains
of transmission causing community-wide
outbreaks
19
00
.
19
03
.
19
06
.
19
09
.
19
12
.
19
15
.
19
18
.
19
21
.
19
24
.
19
27
.
Life expectancy-USA, 1900-28
70
60
50
40
30
19
00
.
19
03
.
19
06
.
19
09
.
19
12
.
19
15
.
19
18
.
19
21
.
19
24
.
19
27
.
Life expectancy-USA, 1900-28
70
60
50
40
30
•
•
•
•
Culling
Quarantine
Disinfection
Vaccination against
circulating flu
• H5N1 vaccine
development
• Stockpiling of
antivirals
Take-home messages
• The threat to public health will remain so long as
the virus continues to cause disease in domestic
poultry
• The outbreaks in poultry are likely to take a very
long time to control
• Should the final prerequisite for a pandemic be
met, the consequences for human health around
the world could be devastating
• Regardless of how the present situation evolves,
the world needs to be better prepared to
respond to the next influenza pandemic
We have to prepare
for the next pandemic!!!
Clinical features of mild and
severe influenza A (H5N1)