The picornaviridae, viruses.
The picornaviridae are small, nonenveloped,
that have a linear, single-stranded,
positive-sense RNA genome.
This genome, because it has a positive sense,
can function as messenger RNA.
There are several very
important picornaviridae and
they're described here.
An easy way to remember them
is the acronym PERCH,
P-E-R-C-H, standing for polio virus,
coxsackieviruses, and the hepatitis A virus.
The polio viruses cause, as you
would imagine, poliomyelitis,
and as we'll talk about in just a bit, there
are vaccine preventions for these.
The others, not as easily vaccine
preventable, with the exception of
hepatitis A virus.
The echoviruses and many other enteroviruses
can cause aseptic meningitis.
Rhinoviruses, the common cold,
you all know about that.
The coxsackie viruses, a whole
list of things, depending
on where the viruses have tissue tropism.
So, central nervous system causing
the mouth causing herpangina,
hand-foot-mouth disease on the skin,
and of course other organ systems
including the heart
with myocarditis, pericarditis, and
even sometimes, enteric systems.
And then hepatitis A virus causing
acute viral hepatitis.
So, one family of viruses,
which actually has a very wide
range of clinical manifestations,
all depending on what target
cell each virus goes for.