Influenza: Disease Analysis

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Influenza Influenza is also referred to as flu and it is a respiratory infection that is caused by viruses which are a significant cause of respiratory disorders in human being and range from seasonal, endemic and pandemic infections. These viruses pass through the airways and enter into the body via the mouth or nose. About 5-20% of the people in the US suffer from the flu every year. There are several strains of the virus and they have been known to cause pandemics that kill millions worldwide. It can be deadly for the vulnerable populations such as the elderly, newborns and those suffering from chronic illnesses(National Institutes of Health, 2012). Influenza is caused by influenza type A and B viruses. The viruses are able to change quickly to respond to selection and to evade B-cell immunity through neutralizing the immunoglobulins. The first process which helps in this is antigenic drift where the viruses mutate rapidly which is a function of the infidelity of RNA polymerases. This mutation alters the major antigenic proteins but maintains the functions. The second process is antigenic shift whereby the virus undergoes a re-assortment of its genome when more than one virus is infected. It is a function of the segmented viral genome. It is a combination of these processes that leads the virus to be able to evade B-cell immunity (Day, André, & Park, 2006). The pathogen originates from birds which are the host species. The influenza virus is transmitted directly
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