influenza virus essays

influenza virus essays Influenza virus is something most people get at least once in their lifetime. It is commonly known as  ¡the flu. ¡ It contains single stranded RNA. It attacks both human and animals. It reproduces in a lytic cycle. It is inhaled and comes in contact with cells of the upper air passage. It penetrates the cells that line these passages and reproduce. New viruses are released from the infected cells and infect other cells along the respiratory tract. It could also be carried away in exhaled air and infect other people. Influenza by itself is not usually a serious disease. But it can lower the body ¡s resistance, and leads to bronchitis and pneumonia especially for elder, innutrition, and people with lung or heart problems. The flu virus was first isolated from chickens in 1901, but it was recognized as so until 1955. The flu virus was also isolated from runny pig snouts in 1931. This virus became know as "swine flu." There are three main types of influenza simply named A, B, C. Influenza A is the most common was discovered in 1933. Influenza B was discovered in 1940 and influenza C in 1947. Variants of these basic types are named after the place it first strikes. For example, there is the Hong Kong (B), New Jersey (A), and Bangkok (A). Symptoms of the virus include a sore throat, fever, fatigue, coughing, aches, and loss of appetite. Influenza not only affects humans but they also infect other animals such as pigs and turkey. Not only that, but it easily crosses species. Thus, new viruses are probably created in pigs and waterfowl, like ducks and seagulls, and then later passed on to other creatures. For example, in 1980, the virus produced an epidemic in seals and caused conjunctivitis in humans who tried to help. The influenza virus can also last for hours in dried mucus. Viruses are usually roughly spherical and about 200nm in diameter. The envelope contains rigid "spikes" of haemagglutinin a ...