influenza strainsInfluenza is synonymous with the flu and is an infectious disease found in mammals and birds.  Influenza is caused by RNA viruses and are referred to as orthomyxoviruses.  Most people are familiar with the symptoms associated with influenza, which include fever and chills, sore throat, runny nose, muscle aches and pains, coughing and fatigue.  More often than not, influenza or flu is transmitted by way of air when individuals/animals cough or sneeze.  However, it is possible to contract influenza by direct contact with bird droppings or nasal secretions. Nevertheless, influenza viruses can be rendered inactive by sunlight, disinfectants and detergents. During flu season, it is suggested to wash hands frequently with soap and water to reduce the risk of infection.  According to the CDC (Centers for Disease Control and Prevention) in Atlanta, GA, seasonal flu vaccines for 2013 to 2014 were made available beginning in August, and somewhere between 135 million and 139 million doses will be produced.  The CDC suggests that if you are 6 months of age or older, you should get vaccinated by October not only to protect yourself but to prevent epidemics as well. [divider] Read the Latest News On Influenza: [feed url=”” number=”5″ ] [divider]

Types of Influenza Viruses

There are  three different classes of influenza viruses known as types A, B, and C.  Types A and B are reported to be responsible for the yearly epidemics that have been observed, while type C carries flu symptoms as well, but not as severe.

Type A

Influenza A viruses affect both animals and humans, however humans tend to suffer more so than animals.  Wild birds also act as hosts for this type of influenza. The A type influenza viruses mutate rapidly and are observed to be responsible for large epidemics.  Individuals who are already infected spread influenza A2 and variants. Type B Influenza type B viruses are only found in humans and tend to be less extreme in symptoms and do not cause pandemics.  They are not classified by subtype. Type C Influenza type C viruses are found in humans but generally milder than types A or B.  Type C does not cause epidemics.

Bird Flu

Bird flu, also known as avian influenza, is also an infectious disease that is caused by strains of influenza type A viruses.  Normally, they only affect birds, however, some will infect humans such as H5N1.  Bird viruses occur naturally and can infect a number of species of birds such as ducks, geese, turkeys, pheasants, quail and chickens.  These viruses are easily spread around the world by migrating birds and have been known to affect domesticated particularly chickens, turkeys and ducks.  Bird influenza viruses don’t generally infect humans but it can happen. [divider] Recent Articles about Bird Flu: [feed url=”” number=”5″ ] [divider]

Influenza Nomenclature

Influenza viruses are listed by a series of letters and numbers and are interpreted as follows: Example:  A/Fujian/411/2002(H3N2) The first letter “A” stands for influence virus A (virus type). “Fujian” represents the geographical origin of that virus. “411” represents the strain number of the virus. “2002” represents the year of isolation of the virus. “H3N2” stands for the virus subtype. In “H3N2” the “H” stands for hemagglutinin (HA), which is a protein found on the surface of the virus.  The “N” stands for neuraminidase (NA), which is another surface protein on the virus. There are 16 different HA subtypes and 9 different NA subtypes of influenza type A.  The 16 HA subtypes and 9 NA subtypes can be combined in different orders to make new subtypes. According to the CDC, there are 15 different influenza A subtypes that can infect birds and 3 subtypes (H1N1, H1N2, H3N2) that can infect humans.

universal influenza vaccineHow do Flu Vaccines Work?

If you receive the flu shot or the nasal-spray vaccine, they cause antibodies to develop in your body around two weeks after you have been vaccinated.  The antibodies that you produce help to protect you against infections from viruses that were in the vaccine.  The typical seasonal flu vaccine guards you against the most common expected viruses for the upcoming season.  Often the vaccines are made to protect against three different viruses (trivalent vaccines) such as influenza A H1N1 and H3N2 and an Influenza B strain.  Some vaccines may include a 4th influenza B virus, referred to as a quadrivalent vaccine. Be aware that viruses are grown under different conditions and are administered in different ways.  Some viruses are grown in eggs and others in cell culture.  Some vaccines are injected into muscle, some injected into the skin and others are nasal sprays.  Different age ranges and health conditions require the administration of different vaccine types. [divider] Read the Latest Articles About Flu Vaccines: [feed url=”” number=”5″ ] [divider]

Do Flu Vaccines Have Side Effects?

One question often asked is, “Will the flu vaccine give me the flu?”  The answer is no: the vaccine is made with inactivated viruses and therefore are not infectious — or the vaccine contains no virus at all (just a protein from the viral surface).  On the other hand, the nasal spray does contain live virus (viruses are not actually alive — the term “live virus” refers to an intact virus). The nasal-spray virus has been weakened (attenuated) and cannot cause flu illness.  The nasal-spray viruses have been cold-adapted, which means they can infect your nasal area (which is a cooler area than inside your body) but cannot infect your lungs, simply because your lungs are too warm to be infected by the cold-adapted virus.

Flu Shot Side Effects

For those who have been administered a flu shot, the side effects should be mild and very temporary. Side effects that have been reported include:

  • Swelling at the site of the injection, redness and soreness
  • Fever (minor)
  • Aches

Nasal Spray Side Effects

The viruses used in the nasal-spray are intact but weakened, so the spray shouldn’t cause severe symptoms of any kind.  Nevertheless, some side effects have been reported in children that include:

  • Fever
  • Runny nose
  • Headache
  • Vomiting
  • Muscle aches


Some side effects have been reported in adults that include runny nose, sore throat, cough and headache. The influenza vaccine is generally well tolerated by patients and for some there may be mild but temporary discomfort.  If you think a flu vaccine has harmed you, you can file a claim for compensation from the National Vaccine Injury Compensation Program (VICP). Need to know where you can a flu shot?  Visit the CDC influenza web site or HealthMap Vaccine Finder.  Perhaps you already have flu and need assistance getting over the flu.  Antiviral drugs are available that will ease your symptoms and make you feel better quicker. Antivirals can also prevent flu-related complications such as viral/bacterial pneumonia.  For more information about antivirals go to Treatment (Antiviral Drugs).

Note: BioNews Texas does not provide medical advice, diagnosis or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.