This is disturbing-
from the London Telegraph - just the intro
Revealed: How coronavirus attacks your veins, heart, brain and blood – as well as lungs
Research suggests the contagion can get deep into our vascular system and even our brains – so how does the virus attack?
By Sarah Newey and Paul Nuki, Global Health Security Editor, London 24 April 2020 • 6:00am
An illustration depicting how coronavirus attacks the body
Doctors are seeing a range of illnesses in Covid-19 patients; some people develop blood clots, others heart attacks or kidney failure
We think of Covid-19 as a respiratory virus – one that simply attacks the lungs.
But scientists are now wondering if it is much more than that, with a stream of medical papers being published over the last few weeks which suggests the contagion can get deep into our vascular system and even our brains.
“We are seeing a range of illness; some people develop blood clots, others heart attacks or kidney failure,” said Prof Ajay Shah, BHF Professor and consultant cardiologist at King's College Hospital, London.
“There are still many unknowns, but the amount of research effort that is going on to try and understand exactly what is happening to patients with Covid is absolutely phenomenal.”
So how does the virus attack?
Nose and throat
It is here that the infection begins, colonising the upper nasal tract, often blocking out our sense of smell, before moving down into the throat.
The cells here are rich in an enzyme known as ACE2. They enable the “spike proteins” on the surface of the virus to latch on and replicate at pace.
At this point patients are highly infectious, but may not yet be suffering any symptoms. It’s one of the virus’s most devious and unusual tricks – to get its human hosts to spread it to others without letting them know they are ill.
Lungs
If the body’s immune system doesn’t kill it off at this early stage, the virus travels down the windpipe and into the lungs.
It is inside the lungs that the virus turns nasty. It invades the millions of tiny air sacs in the lungs, causing them to become inflamed.
“It’s what we would call pneumonitis – inflammation of the lung tissue – and stops the oxygen being taken up properly, it makes the lungs wet and heavy,” said Dr Duncan Young, professor of intensive care medicine at the Nuffield Department of Clinical Neurosciences.
For some patients, this can lead to acute respiratory distress syndrome (ARDS) – a potentially fatal condition where blood oxygen levels drop to a dangerously low level.
“You can stop them dying from a lack of oxygen on a ventilator,” said Dr Young. “But that doesn’t stop the course of the infection, it carries on. You’re keeping them alive hoping that their own immune system fights the virus.”
Unfortunately, for many people, the immune system overreacts to the infection – triggering a a “cytokine storm” whereby the body essentially attacks itself.
“This body-wide inflammatory process causes you to get a high heart rate. It makes blood vessels leak fluid, a bit like a blister. It’s what makes the 20 per cent of people who get kidney failure get kidney failure, and it probably is what causes people to get heart problems,” said Dr Young.
“So when patients die in ICU, they primarily die of this cytokine storm. They die of multiple organ failure as everything gives up.”
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