Colds and the Flu - Highlights

Highlights	Risk Factors	Resources
Introduction	Prevention	References
Diagnosis	Treatment
Complications	Medications

Highlights

Antiviral Drugs for Influenza

The U.S. Centers for Disease Control has recommended that neither amantadine nor rimantadine should be used to treat influenza (flu) during the 2005- 2006 flu season. A high proportion of influenza A strains have become resistant to these drugs.

Oseltamivir (Tamiflu) or zanamivir (Relenza) may be used to prevent or treat complications of the flu. These should not be used for routine treatment of seasonal flu, however. According to an article published in January 2006 in the Lancet, these should be used only during a serious epidemic or pandemic, and in conjunction with public health measures such as quarantine and rigorous hygiene practices.

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Each of the influenza drugs can prevent or reduce symptoms of the flu caused by drug-sensitive strains of the virus. Although amantadine and rimantadine have been very helpful in previous years, drug resistant strains have increased sharply this year. Tamiflu and Relenza remain active against current human influenza virus.

Relenza and Tamiflu reduce ?viral shedding,? or transmission of the flu virus from the nose, although they do not stop viral shedding completely. Amantadine and rimantadine do not reduce viral shedding. Moreover, they encourage flu strains to develop resistance.

New Test for Avian Flu

In February 2006, the U.S. Food & Drug Administration approved a new, faster test for diagnosing strains of avian influenza (bird flu) in people suspected of having the virus. The test is called the Influenza A/H5 (Asian lineage) Virus Real-time RT-PCR Primer and Probe Set. The test gives preliminary results within 4 hours. Older tests required 2 to 3 days. At the time of this publication, at least 165 people have been infected with the avian (H5N1) flu in 6 countries. More than half have died. No cases have been seen in the United States. The avian flu virus has spread from birds to people.

Seasonal Flu Vaccine

The Advisory Committee on Immunization Practices (ACIP) recommends that several additional adult populations receive influenza (flu) vaccinations, including:

All healthcare workers
Patients with any condition that affects breathing
Patients with any condition that produces respiratory secretions (for example, mucus from a runny nose or cough)
People who live with those who are at high risk of flu complications

The CDC recommends that children under 9 years of age receive two doses of the flu vaccine one month apart, because they do not develop a strong immune response from a single dose.