Picornaviruses

00:01 The picornaviridae, viruses.

00:04 The picornaviridae are small, nonenveloped, icosahedral capsids, that have a linear, single-stranded, positive-sense RNA genome.

00:14 This genome, because it has a positive sense, can function as messenger RNA.

00:20 There are several very important picornaviridae and they're described here.

00:25 An easy way to remember them is the acronym PERCH, P-E-R-C-H, standing for polio virus, echovirus, rhinovirus, coxsackieviruses, and the hepatitis A virus.

00:41 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.

00:50 The others, not as easily vaccine preventable, with the exception of hepatitis A virus.

00:56 The echoviruses and many other enteroviruses can cause aseptic meningitis.

01:02 Rhinoviruses, the common cold, you all know about that.

01:06 The coxsackie viruses, a whole list of things, depending on where the viruses have tissue tropism.

01:12 So, central nervous system causing aseptic meningitis, 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.

01:29 And then hepatitis A virus causing acute viral hepatitis.

01:34 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.