Transcript G O N I O S C O P Y M A D E E A S Y

ANTIVIRAL AGENTS FOR THE
PREVENTION AND
TREATMENT ON INFLUENZA
Preventing and reducing the
impact of influenza
• Good personal hygiene: good etiquette when
coughing and sneezing, hand washing
• Protecting others by reducing exposure:
staying at home when ill, reducing workplace
contact, etc.
• Annual vaccination
• Antiviral agents for prevention and treatment
Antivirals for influenza:
Principles of use
• Vaccination is the primary method for the prevention
of influenza
• Antivirals are useful for treatment of influenza and as
a secondary means of preventing influenza
• Antivirals should be used where they have the
greatest benefit
• Antivirals should be used responsibly in order to
minimise the risk of emergence of drug resistance
• It is important that there is adequate availability of
antivirals when required, including stockpiling for
pandemic use
Influenza surface proteins
Neuraminidase
Hemagglutinin
RNA
M2 protein
(only on type A)
Antiviral agents for influenza:
two classes of drugs
• Matrix protein (M2) inhibitors
– amantadine and rimantadine
– inhibit virus coating
– influenza A only
• Neuraminidase inhibitors
– oseltamivir and zanamivir
– inhibit release of virus from infected cells
– active against all known strains of influenza
Antiviral agents for influenza
Class
Drug
M2 Inhibitors
Amantadine
Oral
Rimantadine
Oral
Neuraminidase
Inhibitors
Zanamivir
Oseltamivir
Administration
Inhaled
Oral
Antiviral drugs for influenza
• They may be used to treat influenza but they should
be given within 48 hours of developing symptoms.
• They act by decreasing the severity of illness and
decreasing the duration of illness.
• An adjunct to influenza vaccine for controlling and
preventing influenza but not a substitute for
vaccination.
• Not effective in preventing or treating serious
influenza-related complications (e.g. bacterial or viral
pneumonia or exacerbation of chronic diseases).
M2 inhibitors: Mechanism
Neuraminidase
Hemagglutinin
RNA
H+
H+
H+
H+
X
M2 inhibitors
M2 protein
(only on type A)
• M2 channel allows acidification
of virus
• Initiates uncoating of viral RNA
• Allows viral replication
• M2 inhibitors block this action
By courtesy of APACI
Asia-Pacific Advisory Committee on influenza
www.apaci-flu.com