Poliomyelitis


Description of virus that causes the disease.

- Poliovirus contains a single-stranded RNA genome, about 7500 nucleotides long.
- The viral particle is about 30 nanometers.
- Surrounded by a protein capsid.
- Non-enveloped.
external image Polio-Virus.jpg

Viral Specificity:

-Infects humans only

Classification

-The term poliomyelitis is used to identify the disease cause by any three serotypes of poliovirus which are, Asymptomatic, Minor illness, Paralytic poliomyelitis
-There are three types of paralytic poliomyelitis:spinal polio, bulbar polio, bulbospinal polio
Outcomes of poliovirus infection
Outcome
Proportion of cases
Asymptomatic
90–95%
Minor illness
4–8%
Non-paralytic aseptic
meningitis
1–2%
Paralytic poliomyelitis
0.1–0.5%
— Spinal polio
79% of paralytic cases
— Bulbospinal polio
19% of paralytic cases
— Bulbar polio
2% of paralytic cases

Symptoms and progression of the disease:

-Mild Polio
-Headache
-Nausea
-Vomiting
-General discomfort
-Slight fever for up to three days

-Nonparalytic Polio
-Moderate fever
-Stiff neck and back
-Fatigue
-Muscle pain
-Headache
-Nausea
-Vomiting
-General discomfort

-Paralytic Polio
-Tremor
-Muscle weakness
-Fever
-Stiffness
-Constipation
-Muscle pain
-Spasms
-Difficulty swallowing

-Incubation period is usually 6-20 days, with a maximum of 3-35 days.
-Most infection between 7-10 days before and 7-10 days after appearance of symptoms.

Complications

-musle paresis and paralysis can sometimes result in skeletal defromities, tightening of the joints and movement disability.
-club foot
-external image poliomyelitis.gif

Common Methods of Transmission:

- Highly contagious
- Spread through human to human contact
- Primarily transmitted through the fecal-oral route.
*Contaminated food*
*Contaminated water*
- Occasionally transmitted through the fecal-oral route.

Treatment and Prevention :

-There is no cure for polio.
-Treatment for polio mainly focuses on providing relief from the polio symptoms.
-There are oral and injectable vaccinations for polio.

Miscellaneous:
-The effects of polio have been known since prehistory.
-While now rare in the Western world, polio is still endemic to South Asia and Nigeria.

Resources accessed

http://en.wikipedia.org/wiki/Poliomyelitis
http://polio.emedtv.com/poliovirus/poliomyelitis-virus.html
http://www.dhpe.org/infect/polio.html