2014-2015 Flu Season Indicates Elevated Flu Activity

The Center for Disease Control (CDC) reports elevated flu activity for the 2014- 2015 flu season.

The three strains of flu, that are common are:

  • Influenza A (H1N1) viruses
  • Influenza A (H3N2) viruses
  • Influenza B viruses

Influenza A (H3N2) virus is the predominant strain reported this year and is associated with higher mortality rates than Influenza B (H1N1). Death rates from influenza are higher in young children and adults over 65 years of age. Reports indicate that half the country is experiencing elevated flu activity. “Flu season” varies year to year but most typically begins in December, with some periods reported as commencing as early as October. The current flu season is considered to have begun in December.

Typically an annual pattern for flu shows Influenza Like Illness (ILI) increasing first, with increased hospitalization and increased death rates following in order. This year’s statistics follow that pattern. Flu caused death statistics collected by the Center for Health Statistics are considered incomplete and depressed. Several factors contribute to this including the significant numbers of deaths, deaths listed under a different cause because no flu testing was completed, and deaths that occurred due to secondary conditions that are complicated by flu.

Flu viruses change which cause vaccinations to be less effective against a new strain. The 2014-2015 vaccination, called a trivalent vaccine, was developed to prevent 3 strains of influenza:

  • A/California/7/2009 (H1N1)pdm09-like virus
  • A/Texas/50/2012 (H3N2)-like virus
  • B/Massachusetts/2/2012-like virus

Some of the vaccinations developed for this season also protect against an additional B virus (B/Brisbane/60/2008-like virus); this is called a quadrivalent vaccine. Vaccination does not always prevent the flu.

Many factors contribute to the effectiveness or lack thereof, of vaccinations including age, pre-existing health conditions, changes to the virus, and timing of immunization, to name a few. There are indicators that this year’s vaccine is not highly effective against the predominant strains in circulation this year.

It is possible for children 6 months to 8 years of age to need two doses of vaccination administered four months apart. “Starting in 2014-2015, CDC recommends use of the nasal spray vaccine (LAIV) for healthy children 2 through 8 years of age, when it is immediately available and if the child has no contraindications or precautions to that vaccine. Recent studies suggest that the nasal spray flu vaccine may work better than the flu shot in younger children. However, if the nasal spray vaccine is not immediately available and the flu shot is, children 2 years through 8 years old should get the flu shot.”

There are treatments for the flu, including the new FDA approved drug Rapivab. Antiviral drugs are used to treat flu and prevent serious complications from the flu. The CDC recommends that annual vaccination be combined with daily preventative measures such as washing hands and avoiding contact with others that are sick. Though it is recommended that vaccination be sought as early as October, it is not too late in the season to be vaccinated and protected against acquiring the flu. A flu season can last until May.

Toni Zeller Kohlbeck, student intern Jacoby & Meyers.