3. INDEX
WHAT IS POLIO VIRUS
ICOSAHEDRAL STUCTURE
WHAT ARE SEROTYPES
REANSMISSION OF POLIOVURUS
SYMPTOMS
4. WHAT IS POLIOVIRUS
Poliovirus, the causative agent of poliomyelitis, is a human enterovirus and
member of the family of Picornaviridae. Poliovirus is composed of an RNA
genome and a protein capsid.
Enteroviruses are a gemus of positive-sense single-stranded RNA viruses
associated with several human and mammalian diseases.
A picornavirus is a virus belonging to the family Picornaviridae. Picornaviruses
are small, non-enveloped, positive-stranded RNA viruses with an icosahedral
capsid. The viral particle is about 30nm in diameter.
6. Positive-strand RNA virus: Also known as a sense-strand RNA virus, a virus, whose genetic
information consists of a single strand of RNA that is the positive (or sense) strand which
encodes mRNA (messenger RNA) and protein. Replication in positive-strand RNA viruses is via a
negative-strand intermediate.
A capsid is the protein shell of a virus. It consists of several oligomeric structural subunits made
of protein called protomers. The observable 3-dimensional morphological subunits, which may or
may not correspond to individual proteins, are called capsomers. The capsid encloses the
genetic material of the virus.
7. ICOSAHEDRAL STRUCRURE
• These viruses appear spherical in shape, but a closer
look actually reveals they are icosahedral. The
icosahedron is made up to equilateral triangles fused
together in a spherical shape. This is the most
optimal way of forming a closed shell using identical
protein sub-units. The genetic material is fully
enclosed inside of the capsid. Viruses with
icosahedral structures are released into the
environment when the cell dies, breaks down and
lyses, thus releasing the virions. Examples of viruses
with an icosahedral structure are the poliovirus,
rhinovirus, and adenovirus.
8. WHAT ARE SEROTYPES
A serotype or serovar is a distinct variation within a
species of bacteria or virus or among immune cells of
different individuals. These microorganisms, viruses, or
cells are classified together based on their surface
antigens, allowing the epidemiologic classification of
organisms to the subspecies level
There are tree serotypes of poliovirus with common
antigen. They have identical properties and their genomic
base sequences share 36.52% homology. Poliovirus show
marked antigenic stability.
9. TRANSMISSION OF POLIOVIRUS
Polio is spread when the stool of an infected person is
introduced into the mouth of another person through
contaminated water or food (fecal-oral transmission).
Oral-oral transmission by way of an infected person's
saliva may account for some cases.
10. SYMPTOMS
Signs and symptoms, which can last up to 10 days, include:
Fever
Sore throat
Headache
Vomiting
Fatigue
Back pain or stiffness
Neck pain or stiffness
Pain or stiffness in the arms or legs
Muscle weakness or tenderness
Meningitis
