What is Influenza?
Influenza is a highly contagious viral infection which targets the respiratory system. It is often mistaken for a common cold but is, in fact, a very different illness.
For most people, the virus is not particularly dangerous. However, pregnant women, the elderly and babies or children under the age of two should be closely monitored.
Others who should try to avoid the infection include those with a medical condition likely to be adversely affected by the virus, such as asthma or heart disease (1)
People usually become infected by ingesting airborne droplets following a sneeze or a cough from someone infected. It can also transmit through contact with an object containing the virus, although this scenario is less common.
A virus is a minute, sinister germ, impossible to see with the naked eye. When it enters the body, it quickly accumulates and spreads to begin its path of destruction.
Once the virus is detected, the body will launch its self-defense mechanism; this consists of protein fighters called antibodies.
They will travel through the bloodstream until they reach the virus, attach themselves and destroy the germ.
Influenza is most active during the so-called “flu season.” In the United States, this usually begins during fall months, peaking in February. (3)
Symptoms develop quickly, usually within two days of the virus entering the body, and can include the following: (4)
The average core temperature of the body is 98.6°F (37°C), although it ranges from 97°F to 99°F (36.1o to 37.2oC) in some individuals.
When the temperature exceeds this number, it is classified as a fever. This symptom is caused by a response from the body when a harmful substance, such as a virus or bacteria, is detected.
Influenza will cause a fever which usually reaches about 100°-104°F (38.o-40.oC). This could be even higher, depending on the person. (5)
As the body turns up the heat, chills can occur, generally followed by sweating which acts to lower temperature.
The body temperature in young children may not regulate as easily because they sweat less than adults. Consequently, they could have a more severe reaction to a fever. (6)
A feeling of pain, discomfort and tenderness throughout the body. During a bout of sickness or disease, the body will tire itself from fighting off the virus or bacteria
During influenza, aches and pain usually affect the muscles, joints and chest area. (7)
A headache is pain or discomfort felt around the skull region. It can be mild to severe; some might perceive it as a throbbing or pounding sensation.
During a common cold, one would not usually experience a headache due to the illness. However, in the process of influenza, it is a very common symptom. (8)
When one is feeling the effects of fatigue, it can seem as though all the energy and power has drained from the body.
It can be due to other symptoms, such as body aches or fever, which have exhausted energy supplies. (9)
Alternatively, it may be due to the virus taking its toll on the energy levels as the body works harder to fight it.
Coughing is very common while fighting off either a cold or influenza. However, a cough can be slightly different in influenza.
During a common cold, a cough will typically be referred to as “productive,” which means it produces mucus. On the contrary, during influenza, the cough will normally be dry, or “non-productive,” meaning that mucus is not being secreted. (10)
Runny or Stuffy Nose
Although this symptom fits better within the characteristics of a common cold, it can also make an appearance during influenza.
A runny or stuffy nose occurs when mucus fills up within the nasal cavity. It is characterized by the sudden excessive production of fluid as the sinus swells, partially blocking the airway. Yellow or green mucus is a sign of infection and a doctor should be consulted. (11)
Loss of Appetite
Loss of appetite is when someone lacks a feeling of hunger and therefore finds it difficult to eat.
There may be various reasons why this occurs during influenza. A person might be overly tired and not feel the need for food. It could also arise as a result of other symptoms, such as aches or pains in the head and body. (12)
However, nutrition is essential during sickness; it fuels the body and provides the energy needed to fight off the illness.
Vomiting and/or Diarrhea
These symptoms are usually not classified as indicators of influenza. They are more commonly associated with viral gastroenteritis or “stomach flu.” (13)
However, vomiting and diarrhea are often seen in children during influenza infections, along with general discomfort and pain in the abdomen. (14)
The life cycle of the influenza virus can fall into five stages. Below is a general explanation. (15, 16)
During stage one, the virus has entered the body and is now traveling to the host cell where it will attach itself to the outer surface. On its way, it forms a spiky exterior to help hook on to a cell.
The virus is quickly absorbed, triggering an acidic response. This makes it easier for the germ to infuse deeper into the cell.
The virus is now ready to replicate; but to do so, it must move to another part of the cell, called the nucleus.
The virus will attach itself to a protein after release and then travel to the required destination, where it will settle down and thus begin the next stage.
The virus is ready to replicate, yet it needs some help from the body. Influenza viruses consist of negative ribonucleic acids (RNA), which the cells detect as a hazard and reject. The virus will transform itself from a negative RNA into a positive.
Once positive, the virus is able to trick the cell into assembling a set of genetic material from the germ and, unknowingly, create an outline for the production of more viral RNA traits.
The virus is now being exported out of the nucleus of the cell. This is done by a chain of different genetic materials that work as maintainers and clear out waste.
Now that the virus has been exported to the outer wall of the cell, it will produce viral particles which can travel to other cells and spread the infection.
More proteins are needed to form the new particles; these proteins will travel from another side of the cell to help the virus. Once the particle has been formed, a pathway out of the cell is created by different acidic materials. Thus, the viral particle is ready to spread.
Treatment of influenza can only manage and minimize symptoms; no medication will eliminate the actual virus. For people who find themselves in a risk group, treatment may help prevent serious complications.
Influenza is generally treated with antiviral drugs; these fight the virus and ultimately suppress symptoms. They can be taken in pill form, liquid, inhaled or with an intravenous solution through a vein.
Antiviral drugs work best when administered as early as possible. They may prevent the virus spreading and reduce the risk of life threatening complications. (17)
As far as influenza is concerned, prevention is essential, especially for vulnerable groups. Doctors recommend everyone aged six months and older to take the flu vaccine, thus reducing the risk of contracting and spreading the virus during a flu season. (18)
The vaccine will stimulate antibodies to help fight off the virus before it can begin its transformation and spread.
Different types of flu vaccine are developed from time to time, to keep up with the constant transformation and evolution of the influenza viruses.
What is influenza? Influenza is an infectious airborne virus affecting the respiratory system.
What are the signs of influenza? Symptoms can include; fever and chills, body aches and pain, fatigue or extreme tiredness, cough, runny nose and loss of appetite.
How do you develop influenza? Influenza spreads very easily through contact with infected fluids, such as airborne droplets from an infected person.
How are you diagnosed for influenza? Influenza does not usually require diagnosis, but when it does, there are a few tests available. These can include: a rapid influenza diagnostic test (RIDT) and rapid molecular assays. The latter is more accurate as it can distinguish the material of the virus and thereby make a more detailed diagnosis. (19)
What is the best treatment for influenza? If you do get sick, antiviral drugs may help to speed up the recovery. Otherwise, you should rest completely, allowing your body to use the energy to fight the virus.
What are the long term complications of influenza? Severe influenza can worsen already existing conditions, such as heart disease, diabetes and asthma. It can also make way for lung infections, and even inflammation in the heart, brain or muscles, as well as organ failure. (20)
Is influenza considered a disability? Influenza on its own is not a disability.
Is there any cure for influenza? The illness is treatable with antiviral drugs which can suppress symptoms. Otherwise, influenza will generally run its course.
Is influenza life threatening? Yes, it can trigger complications which can lead to life threatening outcomes. (21)
Influenza is a highly contagious disease, caused by a type of influenza virus which affects the respiratory system.
You may have influenza if you develop a high fever, dry cough, body aches and feel totally exhausted. Antiviral drugs can usually alleviate some or all of the symptoms.
However, to reduce risk of contracting the virus, doctors recommend a flu vaccination every 6 months.