Influenza B,Τι είναι η ύπουλη γρίπη τύπου Β

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It is common knowledge that taking good care of oneself can help prevent a lot of illnesses as well as decrease the severity of illness in the body. This is no different for colds and the flu. Healthy lifestyle choices include proper nutrition, rest and minimizing stress. These healthy habits help ensure that one’s immune system is in the best shape it can be. Also, if you get a cold or the flu, it is important that you accept your sickness and rest. Some would say it’s a sign that the body needs to rest and get equilibrated. In addition, there are a few other things that are easy enough to do to help combat the common cold and flu.

Influenza B is a type of flu that is similar to influenza A. However, while A usually afflicts people in the early winter, influenza B can infect any time of the year. Another difference between the two,is that type B can only pass from human to human unlike type A bird flu or swine flu. However, researchers have found that gray and harbor seals can contract influenza B as well.

Type A and B share many symptoms.

Body Symptoms
One of the earliest symptoms of type B influenza is a fever. The National Institute of Health reports that the fever can come on quickly and go as high as 106 degrees. However, according to the Penn State College of Medicine, while A and B influenza share the same symptoms, type B generally produces much milder symptoms, so the fever will not be as acute. Also, the National Institutes of Health (NIH) reports that adults usually have a lower fever temperature than children do. The fever is often accompanied by body aches and fatigue.

Respiratory Symptoms
Penn State Medical Center also reports that as the fever begins to leave, respiratory symptoms begin to develop. These symptoms are a stuffy or runny nose, cough and sore throat. These symptoms can become worse over time, and even turn into bronchitis or pneumonia if not treated. While these symptoms will usually disappear within a week, the cough can remain for several weeks.

Stomach Symptoms
There are times when type B influenza can affect the stomach also, which is why some people refer to it as the "stomach flu." The stomach flu is not a different type of flu virus; it is simply symptoms of the flu that affect the stomach. Some of these symptoms, as listed by the NIH, include vomiting, nausea and loss of appetite.

Influenza B symptoms, while the same as influenza A symptoms, are not quite as severe in their intensity. When you get a flu shot, it is meant to protect you from both influenza A and B strains.

Types, Subtypes and Strains
Influenza A and B viruses are genetically similar enough to be included in the same family of viruses, the Orthomyxoviridae family. However, their genetic differences are significant enough to warrant separating the viruses into two different types, A and B. Influenza A viruses are further categorized by subtype and strain. Influenza B viruses are categorized only by strain. This difference is due to the more rapid mutation rate seen in influenza A viruses compared to influenza B viruses.

Clinical Illness
Influenza A and B viruses both cause the illness we recognize as the flu with fever, headache, dry cough, fatigue, muscle aches, sore throat and a runny or stuffy nose. However, the illness caused by the influenza type A virus is usually more severe than that caused by influenza type B.

Mutation Rate
Influenza A viruses are in a perpetual state of change. Spontaneous changes called mutations occur frequently in their genes. From one flu season to the next, genetic changes in the circulating influenza A viruses are extensive enough to cause the virus to go unrecognized by the immune system—even if you had the flu shot or the flu the previous year. This is why you need a flu shot every year; the shot from the previous year cannot protect you against the newly mutated influenza A virus.

Influenza B viruses mutate more slowly than influenza A viruses. Whereas influenza A viruses change significantly from one flu season to the next, influenza B viruses typically change significantly only every few years.

Pandemic Potential
The high mutation rate of influenza A viruses combined with their broader range of hosts imparts these viruses with pandemic potential that influenza B viruses do not have. All of the influenza pandemics that have occurred in modern times, beginning with the Spa