It’s The Flu Season Time Of Year Again… Well, it’s that time of year again. Winter coats and sweaters are dusted off and your flip-flops are packed away until it’s time to hit the beaches again. While the holiday season brings gifts, cheer and family reunions, it also brings flu season with it. Don’t get so wrapped up in the holiday festivities that you forget to take precautions against the flu, it’s much more serious than you may think! The annual flu (also called “seasonal flu” or “human flu”) in the U.S. “results in approximately 36,000 deaths and more than 200,000 hospitalizations each year.” In addition to this human toll, influenza is annually responsible for a total cost of over $10 billion in the U.S.
Facts About Flu Season, The Flu, And How You Can Protect Yourself…
Flu season is a term used to describe the regular outbreak in flu cases during the cold half of the year. Flu activity can sometimes be predicted and even tracked geographically. While the beginning of major flu activity in each season varies by location, in any specific location these minor epidemics usually take about 3 weeks to peak and another 3 weeks to significantly diminish.
The garden variety flu that comes around every year is caused by Influenzavirus A, Influenzavirus B, or Influenzavirus C and are also known as human flu virus strains which is to say it has made genetic changes to adapt to its human hosts. It passes from human to human all year round and never goes away completely. When it is cold (winter in the north, summer in the southern part of the world) infection from “human flu” increases something like ten fold or more. Different strains of flu virus circulate in different years as it is constantly mutating. The flu vaccine for the 2005 – 2006 flu season contains proteins from the coat of two subtypes of species A and from species B. Species B and C don’t have subtypes.
It remains unclear why outbreaks of the flu occur seasonally rather than uniformly throughout the year. One possible explanation is that, because people are indoors more often during the winter, they are in close contact more often, and this promotes transmission from person to person. Another is that cold temperatures lead to drier air, which may dehydrate mucus, preventing the body from effectively expelling virus particles. The virus may also linger longer on exposed surfaces (doorknobs, countertops, etc.) in colder temperatures. Increased travel and visitation due to the holiday season may also play a role.
Typically, influenza is transmitted from infected mammals through the air by coughs or sneezes creating aerosols containing the virus, and from infected birds through their droppings. Influenza can also be transmitted by saliva, nasal secretions, feces and blood. Infections either occur through direct contact with these bodily fluids, or by contact with contaminated surfaces. Flu viruses can remain infectious for over 30 days at 32°F and about one week at human body temperature, although they are rapidly inactivated by disinfectants and detergents.
In humans, influenza’s effects are much more severe than those of the common cold, and last longer. Recovery takes about one to two weeks. Influenza can be deadly, especially for the weak, old or chronically ill.
The virus attacks the respiratory tract and can cause the following symptoms:
- Body aches, especially joints and throat
- Coughing and sneezing
- Extreme coldness and fever
- Irritated watering eyes
- Nasal congestion
- Nausea and vomiting
- Reddened eyes, skin (especially face), mouth, throat and nose
It can be difficult to distinguish between the common cold and influenza in the early stages of these infections. Since anti-viral drugs are most effective in treating influenza if given early, it can be important to identify cases early. Of the symptoms listed above, a combination of cough, fever and nasal congestion is good evidence that the infection is influenza. Vaccination against influenza with a flu vaccine is strongly recommended for high-risk groups, such as children and the elderly.