Influenza is an RNA virus that infects birds and mammals, including humans.
Influenza comes in three strains: influenzavirus A,B, and C.
Typically spherical in shape and 80-120 nanometres in diameter.
Virus is enveloped containing two main types of glycoproteins wrapped around a central core.
RNA is within central core and is usually double-stranded.
Influenza A and B most severe and common while C is usually not as harmful and shows little to no symptoms.
Influenza A is transmitted mostly through wild aquatic birds.
Most virulent pathogen among humans.
Examples include Spanish flu, Swine flu, Bird flu, and Asian flu.
Influenza B is not as dangerous and infects mostly humans, seals, and ferrets.
Mutates slower than Influenza A which increases immunity.
Viral Specificity:
Influenza infects the nose, throat, and bronchial tubes.
Parts become enflamed,sore, and irritable.
Influenza only infects birds, mammals, and humans.
File:H1N1 versus H5N1 pathology.png
- Areas of the body affected by Influenza.
Symptoms and progression of the disease:
Visible symptoms occur one to two days after infection.
Common symptoms include: the chills, fever, sore throat, muscle pains, severe headaches, coughing, weakness and fatique.
Symptoms usually reach their peak severity around three to four days.
Common Methods of Transmission:
Many modes of transmission.
Transmitted throught the air by coughs or sneezes.
Bird droppings, nasal secretions or contact with contaminated surfaces.
Spreads in seasonal epidemics.
Has led to many epidemics and pandemics such as the Spanish flu.
The time at which a person becomes infectious is one day before first symptoms.
People become most infective between the second and third days.
As a person's fever increases, so does the likelihood of infecting others.
Treatment and Prevention:
Immunizations are given yearly in developed countries.
Influenza is highly adaptable and constantly evolving and replacing older strains.
Immunizations do not provide permanent immunity.
Most common type of vaccine is a trivalent vaccine that contains purified and inactivated antigens.
Immunization must occur within one week to four months prior to exposure.
Cases are most serious in the elderly, young children and those with weak immune systems.
Previous exposure does not guarantee immunity.
Common ways to combat virus include: bed rest, drinking fluids, tylenol or ibuprofen, and antiviral antibiotics.
Virus can be inactivated through sunlight, disinfectants, and detergents.
Frequent handwashing reduces the risk of infection.
Miscellaneous:
Results in 250,00 - 500,000 deaths yearly.
On average, 41,400 people died yearly in the United States between 1979-2001.
Distantly related to the human parainfluenza viruses
50 to 100 million people, or 3% of the world's population at the time, were killed as a result of Spanish flu with another 500 million, or 23% of the world population infected.
More people died because of Spanish flu than World War 1.
Although somewhat of a cliche, washing your hands is an EXTREMELY effective way of preventing the disease.
Influenza
Description of Virus:
Viral Specificity:
Symptoms and progression of the disease:
Common Methods of Transmission:
Treatment and Prevention:
Miscellaneous:
Resources accessed: