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 M 2 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

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). Antiviral drugs for influenza

M2 inhibitors: Mechanism Neuraminidase Hemagglutinin RNA M2 protein (only on type A) H+H+ H+H+ H+H+ H+H+ X M2 inhibitors 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