How does the poliovirus replicate?
The virus enters through the mouth and multiplies in the throat and gastrointestinal tract, then moves into the bloodstream and is carried to the central nervous system where it replicates and destroys the motor neuron cells.
Where does poliovirus replicate in the cell?
Poliovirus replication occurs on membranous vesicles, and 2C and 3A are both membrane-associated proteins that are essential components of the poliovirus replication complex (44, 47). BFA appears to prevent the formation of the poliovirus-induced vesicles necessary for replication (31).
Is viral replication intracellular?
As viruses are obligate intracellular pathogens they cannot replicate without the machinery and metabolism of a host cell.
Are viruses intracellular or extracellular?
Viruses are obligate intracellular parasites and their reproduction entirely relies on the host cell machinery for the synthesis of viral components such as nucleic acids, proteins and membranes.
Why does poliovirus spread to the CNS?
In humans, paralytic poliomyelitis results from the invasion of the central nervous system (CNS) by circulating poliovirus (PV) via the blood–brain barrier (BBB). After the virus enters the CNS, it replicates in neurons, especially in motor neurons, inducing the cell death that causes paralytic poliomyelitis.
What type of human cell does the poliovirus infect?
In the event that polio infects CNS cells, it can then replicate in motor neurons in the anteriror horn and the brain stem. The damage caused by this can result in nervous cell and tissue destruction, leading to the symptoms of paralysis in polio victims (17).
What causes Hepadnavirus?
It can be caused by hepatitis viruses (not necessarily in the Hepadnavirus family), other viruses, amebas, and non-infectious agents such as alcohol and acetaminophen. The hepadnaviurses include three viruses of mammals and two viruses of birds.
Is poliovirus a picornavirus?
The viruses in this family can cause a range of diseases including the common cold, poliomyelitis, meningitis, hepatitis, and paralysis….Picornavirus.
| Picornaviridae | |
|---|---|
| Electronmicrograph of poliovirus | |
| Isosurface of a human rhinovirus showing protein spikes | |
| Virus classification | |
| (unranked): | Virus |
What are intracellular viruses?
Viruses are small obligate intracellular parasites, which by definition contain either a RNA or DNA genome surrounded by a protective, virus-coded protein coat. Viruses may be viewed as mobile genetic elements, most probably of cellular origin and characterized by a long co-evolution of virus and host.
Are all viruses intracellular?
What neurons in the CNS must the poliovirus infect that causes muscle weakness?
Acute poliomyelitis is a disease of the anterior horn motor neurons of the spinal cord and brain stem caused by poliovirus. Flaccid asymmetric weakness and muscle atrophy are the hallmarks of its clinical manifestations, due to loss of motor neurons and denervation of their associated skeletal muscles.
