Influenza (or as it is commonly known, the flu) is a contagious disease caused by an RNA virus of the orthomyxoviridae family. The name comes from the old medical belief in unfavourable astrological influences as the cause of the disease.
There are three types of the virus:
The virus attacks the respiratory tract, is transmitted from person to person by droplets, and causes the following symptoms:
Most people who get influenza will recover in one to two weeks, but some people will develop life-threatening complications (such as pneumonia) as a result of the flu. Millions of people in the United States — about 10% to 20% of U.S. residents — will get influenza each year. An average of about 36,000 people per year in the United States die from influenza, and 114,000 per year have to be admitted to the hospital as a result of influenza. Anyone can get the flu (even healthy people), and serious problems from influenza can happen at any age. People age 65 years and older, people of any age with chronic medical conditions, and very young children are more likely to get complications from influenza. Pneumonia, bronchitis, and sinus and ear infections are three examples of complications from flu.
The flu can make chronic health problems worse. For example, people with asthma may experience asthma attacks while they have the flu, and people with chronic congestive heart failure may have worsening of this condition that is triggered by the flu.
Influenza is an extremely variable disease: similar viruses are found in pigs and domestic fowl. In areas where there are high concentrations of humans, pigs and birds in close proximity, such as parts of Asia, simultaneous infections across species enable genetic material to be exchanged between the various strains of flu. This appears to be the principal method by which new infectious strains arise. It is believed that sooner or later, a recombination may occur to produce a strain as lethal as the 1918 virus. In late 1997, a new strain of influenza originating from chickens infected 18 people in Hong Kong, of whom 6 died. This strain did not appear to be readily transmissible from human to human, but such a high mortality rate, and the possibility of a further recombination to make it more infectious, meant that the risk was considered so great that all domestic poultry in Hong Kong was slaughtered. As of April 2002, there have been no further human infections with this particular strain.
| Table of contents |
|
2 Treatment 3 The Myth of the "Stomach Flu" 4 External Links |
Prevention
It is possible to get vaccinated against Influenza, however due to the high mutability of the virus the vaccine is usually only good for a year or so. The World Health Organization co-ordinates the contents of the vaccine each year to contain the most likely strains of the virus to attack the next year. The vaccine is usually recommended for anyone in a high-risk group who may suffer complications from a real flu attack.
Many people use the term "stomach flu" to describe illnesses with nausea, vomiting, or diarrhea. These symptoms can be caused by many different viruses, bacteria, or even parasites. While vomiting, diarrhea, and being nauseous or “sick to your stomach” can sometimes be related to influenza — particularly in children — these problems are rarely the main symptoms of the infection. The flu is a respiratory disease and not a stomach or intestinal disease.
See also: Infectious diseases, Pandemic
Some of this article has been taken from the public domain CDC publication http://www.cdc.gov/ncidod/diseases/flu/fluinfo.htm Treatment
Antiviral treatments :
The Myth of the "Stomach Flu"
External Links