Coxsackievirus

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Coxsackievirus, sometimes referred to as Coxsackie’s virus is part of the enterovirus genus of the picornavirus family, named after Coxsackie village in New York, the place where it was first isolated.

Coxsackievirus is surrounded by an icosahedral capsid, which is a spherical protein shell made up of 20 equilateral triangular faces. Nonetheless, it’s a naked virus because the capsid isn’t covered by a lipid membrane.

It’s also a positive sense single strand virus. This means that its RNA is actually mRNA – and the host cell ribosomes use this mRNA to make one long polyprotein chain, which is then broken into smaller pieces by viral proteases. This all happens in the cytoplasm of the host cell, since that’s where ribosomes are found, and results in several viral proteins.

Coxsackievirus is primarily transmitted from person to person via the fecal-oral route. In other words, you catch it by ingesting stool particles of someone who is sick… yuck. This can happen if infected stool ends up in the water supply or on agricultural fields, if flies land on it, and transfer stool particles to other places, or by touching contaminated surfaces. You can summarize it as the four Fs: fluid, fields, flies, and fingers. As a result, coxsackievirus can end up in food and drinking water. It can also be spread by respiratory droplets when someone sneezes or coughs.

After it enters the body, the virus first replicates in cells of the pharynx and the terminal ileum. From there, the virus enters blood vessels and travels to lymphatic tissue throughout the body. This initial viral presence in the blood is called minor viremia because it’s a relatively small amount of virus.

Alright, Coxsackievirus counts over two dozens serotypes, but they can be grouped in only two groups; A and B based on their pathophysiology. Starting with Group A, it most commonly affects children under five years, and it generally prefers infecting the skin and mucous membranes. The most known serotype of this group is A16, known to cause the hand-foot-mouth disease, called so because it causes tiny blisters on those body parts. Other concerning serotypes include A25 that causes hemorrhagic conjunctivitis, and A7 that causes polio-like permanent paralysis though it’s rare.

On the flip side, group B prefers going deeper into the body, infecting visceral organs and causing problems like gastroenteritis if it affects the gut, pericarditis in case it infects the pericardium, which is that tough membrane that envelopes the heart, or even causing myocarditis, which happens when it infects the heart muscle, resulting in coxsackievirus-induced cardiomyopathy.

Key Takeaways

Coxsackievirus is a single-stranded RNA virus belonging to the enterovirus genus and the picornaviridae family. It primarily affects the gastrointestinal tract and is mainly transmitted via the feco-oral route. Based on its pathogenicity, Coxsackievirus is divided into two groups: A and B. Coxsackievirus group A affects the skin and mucous membranes, causing hand-foot-mouth disease in children, and coxsackievirus group B, affects internal organs, resulting in more severe conditions such as gastroenteritis, pericarditis, myocarditis, and encephalitis.