A seasonal Flu outbreak is almost as widely known as any other form of illness. The cause of flu is a virus called influenza virus. The virus is mainly of three types: A, B and C. While type C is mostly known to affect ducks, geese, turkeys and chickens, a tiny percentage of cases involving humans affected by the virus have been reported. Type B on the other hand, is widely found to affect only humans and causes a mild infection and changes very little from year to year. The type A and type B viruses are the main causes of influenza outbreak, seasonally.
The type A virus is mostly common in animals like horses, pigs, ducks and chickens, however, it has the ability to affect different species including birds, seals, whales and humans. The strains of this type have been found in all of these species. This is the influenza virus that causes most problems for humans. The cause of influenza is that the viruses tends to affect two different species can combine and through genetic mix and matching of information, these can create a new strain. The problem arises as nobody is immune to these new viruses and there is no vaccine that has been prepared. There can be infinite new varieties of the A type virus.
The main type A viruses that we have seen in the recent past include, avian flu and H1N1. Avian flu had been seen only in birds, including chickens and ducks until 1997. The first human case was reported in Hong Kong. The flu which was till date then, mostly known to affect animals caused a few cases of severe disease with a high risk of death in humans. This resulted in slaughtering of many birds in Hong Kong to prevent the spread of the disease. In early 2004, countries like Japan, South Korea, Vietnam, Thailand, Cambodia, China, and Indonesia were again affected by the Avian Flu. There were again reports of human cases in Vietnam and Thailand and it leads to millions of chickens being killed in an attempt to stop the spreading disease.
Also Read: Important nutrients every man needs
The other, H1N1 was actually the human swine flu. The type of influenza A that normally affected pigs, and is the cause of flu is passed on from pig to pig, and a few cases of the infections were found in humans. This was then known as H1N1 flu virus or human swine flu. Most of the cases were in people who had direct exposure to the pigs like people who were working on pig farms. Transmission of the H1N1 flu virus from one person to another takes place, however, it is not clear how the virus spreads among people.
Influenza is a contagious disease. This means the cause of flu spreading is from a person to another person. The causes of influenza being spread can be many. The most common cause of flu can be through coughing and sneezing. Infected droplets of respiratory fluids that get mixed in the air may cause the virus to be airborne. Other people inhale the airborne virus and can become infected. The other cause of influenza can be getting infected by touching a contaminated surface like doorknobs, countertops, telephones etc. and then touching his or her nose, mouth, or eyes,. The flu is most easily spread in crowded places such as schools and offices.
Also Read: Remedies to improve nasal congestion
To incubate in humans the influenza virus takes 1 to 4 days. But the infection of the may be present even before the symptoms start to manifest. Often this is just a day after the influenza virus enters the body. Since the symptoms develop a day after the person gets infected, a person may be passing on the flu before ever knowing that they are affected by it. Adults remain affected for up to 6 days and in children the infection remains for up to 10 days.