AHMAD GONBOS
Unit 12: Diseases and Infection
Aim C: Understand how infectious diseases can be treated and managed
Describe the method available to treat a type of infectious
diseases.
Flu is a viral disease that is characterized by a widespread seasonal outbreak. The cause of
the virus is the influenza virus, which is transmitted from person to person through the
respiratory system. Influenza viruses change over time, this is means there is not only one or
more specific viruses of a specific virus that activates or infects humans and they are
constantly changing viruses. This constant change enables the virus to invade and attack the
immune system, so a person is exposed throughout his life to infection with the influenza
virus.
The flu has several unique features that include:
Fixed seasonality: Influenza spread in winter in the northern hemisphere, in summer in the
southern hemisphere and in rainy seasons in the tropics.
The ability to change: The influenza virus changes, at a high rate, the structure of proteins
on its surface, deceiving the immune system that had produced antibodies against the
previous version of it. Thus, the disease can affect the same person more than once.
The spread of the disease on a large scale: When the flu spreads, it affects a very large
number of children and adults (about a third of children and 10% of adults), which leads to
frequent absences from work and school, and creates severe pressure on hospitals and
clinics.
Causes
Flu is caused by influenza viruses of type A, B, or C. Influenza viruses of type A and B are
responsible for epidemics of respiratory diseases that occur almost every winter. As for
influenza viruses of type C, they cause respiratory disease much less severe than the
previous two types. Or, it may not show any symptoms at all, as it is not a pandemic, and
has no serious public health impact. It is worth noting that influenza vaccine is vaccinated
against types A and B only. It is also worth noting that influenza A virus infects many
animals, including ducks, chickens, pigs, whales, horses, and seals, while type B affects only
humans.
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Unit 12: Diseases and Infection
Aim C: Understand how infectious diseases can be treated and managed
Describe the method available to treat a type of infectious
diseases.
Flu is a viral disease that is characterized by a widespread seasonal outbreak. The cause of
the virus is the influenza virus, which is transmitted from person to person through the
respiratory system. Influenza viruses change over time, this is means there is not only one or
more specific viruses of a specific virus that activates or infects humans and they are
constantly changing viruses. This constant change enables the virus to invade and attack the
immune system, so a person is exposed throughout his life to infection with the influenza
virus.
The flu has several unique features that include:
Fixed seasonality: Influenza spread in winter in the northern hemisphere, in summer in the
southern hemisphere and in rainy seasons in the tropics.
The ability to change: The influenza virus changes, at a high rate, the structure of proteins
on its surface, deceiving the immune system that had produced antibodies against the
previous version of it. Thus, the disease can affect the same person more than once.
The spread of the disease on a large scale: When the flu spreads, it affects a very large
number of children and adults (about a third of children and 10% of adults), which leads to
frequent absences from work and school, and creates severe pressure on hospitals and
clinics.
Causes
Flu is caused by influenza viruses of type A, B, or C. Influenza viruses of type A and B are
responsible for epidemics of respiratory diseases that occur almost every winter. As for
influenza viruses of type C, they cause respiratory disease much less severe than the
previous two types. Or, it may not show any symptoms at all, as it is not a pandemic, and
has no serious public health impact. It is worth noting that influenza vaccine is vaccinated
against types A and B only. It is also worth noting that influenza A virus infects many
animals, including ducks, chickens, pigs, whales, horses, and seals, while type B affects only
humans.
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