The winter season is generally filled with an abundance of family time, holiday and dinner parties, and plenty cold nights. What is clear here despite these occasions, is the close proximity that we spend indoors with one another. Many folks remember the historic pandemic of the H1N1 flu that at the June 25, 2009, Advisory Committee on Immunization Practices Meeting, the CDC estimated it affected at least 1 million people in the United States alone.

Recently, we have been seeing and experiencing yet another episode of patients both young and old suffering from the deadly effects of this virus.

Credit: Centers for Disease Control and Prevention

WHAT IS IT?

The Centers for Disease Control and Prevention, commonly referred to as the CDC, defines the influenza virus as a contagious respiratory illness caused by influenza viruses that infect the nose, throat, and sometimes the lungs. The organization says that it can cause mild to severe illness, and at times can lead to death.

Some of the symptoms can include a sudden onset of fever, sore throat, nasal discharge, chills, headache, muscle aches and loss of appetite among other things.

With that said, a couple questions always remain: Why does it occur typically in the winter months and does the weather have an effect on the spread of the flu?

Credit: Centers for Disease Control and Prevention

WHEN DOES IT OCCUR?

In the winter months when we are all closely tied to our significant others, family members, friends, co-workers and children’s school events, a sharp rise in respiratory infections tend to occur – sometimes as a common cold, other times as the flu.

In the U.S., the flu season occurs during fall and winter with the peak of the flu season anywhere from late November to March. During this time, we tend to also see an increase in severe weather due to the change of the seasons. The fall and spring equinoxes tend to incorporate gusty winds, rain showers, seemingly warm and mild days, and chilly and wet nights. Thus, we tend to bundle ourselves up with warm clothes, and for some of us, we tend to negate the swift changes in the weather from day to day, and usually from hour to hour, so we may forget that heavy coat and umbrella that’s needed on Tuesday, despite the warm and sunny weather the previous day on Monday.

The usual pattern is for a rise in the incidence of flu in children, which precedes an increase in the adult population. Presumably children are infected at school, bring the virus home and infect their siblings and parents. The parents then pass on the flu to their friends and fellow workers, with a second generational leap upwards to the elderly. Nursing home epidemics are common, and that is where most of the serious complications and deaths due to flu occur.

Credit: Centers for Disease Control and Prevention

HOW DOES IT SPREAD?

It has been studied that the flu is spread by a droplet, an aerosol, infection from individuals with a high viral level in their nasal and throat secretions. In other words, through sneezing or coughing, or shaking hands upon greeting individuals. Depending on the size of the droplet, it can remain airborne and be breathed in by an unsuspecting victim during interactions whether close or up to six feet away.

So to answer the question if the weather has any significant influence on the spread of the flu, there is no evidence that proves this notion. The best advice for all is to wash your hands frequently and get your flu shot annually.