When Flu Shots Miss The Mark, Try Antiviral Drugs

The flu activity in the USA has increased significantly over recent weeks with influenza A (H3N2) viruses predominating this season.

The Walgreens Flu Index weekly report identified Texas, Arkansas, and Tennessee as the leading states with influenza.

And in Texas, the Dallas County Health and Human Services is reporting the fifth flu-related death this year.

Dr. Peter Hotez, the Dean for the National School of Tropical Medicine at the Baylor College of Medicine, told the Dallas news radio KRLD that ‘even if the flu shot does not prevent catching the virus, it could minimize the risk for flu-related complications like respiratory infections.’

In the past, influenza vaccine effectiveness (VE) has been lower against A (H3N2) viruses than against influenza A (H1N1)pdm09 or influenza B viruses, reports the Centers for Disease Control and Prevention (CDC).

The CDC found that during the 2016 flu season, the VE against circulating influenza A (H3N2) viruses was estimated to be just 32 percent.  

For the 2017/2018 flu season, the CDC expects that the flu vaccine effectiveness could be similar.

Which means, the use of antiviral medications for treatment of influenza becomes even more important.

Antiviral drugs are prescription medicine pills, liquid, an inhaled powder, or an intravenous solution. Antiviral drugs are different from antibiotics, which fight against bacterial infections.

Neuraminidase inhibitor (NAI) antiviral medications are most effective in treating influenza and reducing complications when treatment is started early, says the CDC.

An unpublished CDC qualitative research shows that most people interviewed were not aware that drugs to treat influenza illness are available.

The FDA recommends these antivirals for use during the 2017–2018 influenza season:

• oseltamivir (Tamiflu)
• zanamivir (Relenza)
• peramivir (Rapivab)

Ideally, treatment should be initiated within 48 hours of flu symptom onset.

NAI can reduce the duration of uncomplicated influenza illness by approximately 1 day when started within 2 days after illness onset, in otherwise healthy persons.

Additionally, because of the importance of early treatment, starting antiviral treatment should not wait for laboratory confirmation of influenza.

A very large observational study of more than 29,000 hospitalized influenza patients reported that the greatest clinical benefit was found when antiviral treatment was initiated within 48 hours of illness onset.

And, starting treatment after 2 days also delivered benefits in adults, versus no treatment.

Most pharmacies in the USA offer FDA approved flu vaccines.

The flu shot cost varies depending on your insurance and which state you live. The CDC Vaccine Price List provides the private sector vaccine prices for general information.

Flu vaccine discounts can be found here.

Vaccines, like any medicine, can have side effects, says the CDC. You are encouraged to report negative side effects of vaccines to the FDA or CDC.