How does CoronaVirus Attack Her Suffering Body?
Globally, this virus has infected at least 2,332,471 people, with 600,006 people declared to have recovered.
The so-called corona virus was first identified in Wuhan, China, killing 160,784 people.
So, how does this virus attack the body?
Launch Sciencemag, a lung doctor and critical care at the Tulane University School of Medicine, Joshua Denson observed two patients experiencing seizures, many patients with respiratory failure and others with kidney problems.
A few days earlier, the team in charge of the ICU room tried to revive a young woman whose heart had stopped working, but the attempt failed.
"They are all positive at Covid," Joshua said.
When the number of positive cases of Covid-29 worldwide exceeds 2 million and the number of deaths exceeds 150,000, doctors and pathologists struggle to understand the damage to the body caused by the corona virus.
The doctors and experts are aware that even though the lungs are the zero point, their range can extend to many organs including the heart, blood vessels, kidneys, intestines, and brain.
"(Disease) can strike almost anything in the body with devastating consequences," said cardiologist at Yale University and Yale-New Haven Hospital, Harlan Krumholz, who led various efforts to collect clinical data on Covid-19.
Further research
Understanding the rage of the corona virus can help doctors treat a small proportion of infected people who become very ill and sometimes mysteriously ill.
"Taking a systems approach might be beneficial when we start thinking about therapy," said Patchouli Mangalmurti, a pulmonary intensivator at the University of Pennsylvania Hospital (HUP).
The corona virus attacks cells around the body, especially in about 5 percent of patients who become critically ill.the clear picture is still difficult to understand because viruses act like no microbe has ever been seen by humans.
Without a larger prospective controlled study that has just been launched, scientists must draw information from small studies and existing case reports.
"We remain open-minded as this phenomenon continues," said a liver transplant doctor who had treated Covid-19 patients at Rush University Medical Center Nancy Reau.
Infection begins
When an infected person takes out a droplet or droplets full of viruses and is inhaled by other people, the corona virus will enter the nose and throat.
In the nasal lining, it is rich in cell surface receptors called angiotensin-converting enzyme 2 (ACE2).
The presence of ACE2 throughout the body, usually helps regulate blood pressure and mark tissue that is vulnerable to infection, because the virus requires the receptor to enter the cell.
Once inside, the virus hijacks the cell machine and makes many copies of itself which then attack new cells.
When the virus multiplies, the infected person can reduce that number, especially during the first week or so.
Symptoms may not appear at this time or new victims of the corona virus may experience fever, dry cough, sore throat, loss of smell and taste or headache.
Initial phase of infection
If the immune system does not defeat SARS-CoV-2 during the initial phase, the virus then lines up to the throat to attack the lungs, where this condition can be deadly.
The thinner branches, far from the respiratory tree of the lung, end up in small air sacs called alveoli, each covered by a layer of cells that is also rich in ACE2 receptors.
Normally, oxygen crosses the alveoli into capillaries, small blood vessels located next to the air sacs, then oxygen is carried throughout the body.however, when the immune system is at war, this will disrupt oxygen transfer.
White blood cells release inflammatory molecules called chemokines, which in turn call for more immune cells that target and kill cells infected with the virus, leaving stews fluid and dead cells such as pus.
This is the pathology underlying pneunomia, with symptoms of cough, fever, rapid and shallow breathing.
Some Covid-19 patients recover, sometimes without more support than oxygen is inhaled through the nasal branches.
However, others often get worse suddenly, developing a condition called acute respiratory distress syndrome (ARDS).
Attacking the lungs
The oxygen level in the patient's blood drops and makes them struggle harder to breathe.
On computerized x-rays and computerized tomography scans, the lungs are full of white murals where the black space should be filled with air.
Generally, these patients end up on a ventilator and many die.
An autopsy showed that the alveoli became filled with fluid, white blood cells, mucus, and detritus of the destroyed lung cells.
In serious cases, SARS-CoV-2 in the lungs can cause severe damage there.however, a virus or the body's response to it, can injure many other organs.
Some doctors suspect the driving force of terminally ill patients is an overreaction from the immune system known as a cytokine storm that is known to trigger other viral infections.
Cytokines are chemical signaling molecules that guide healthy immune responses; but in cytokine storms, certain cytokine levels soar far beyond what is needed, and immune cells begin to attack healthy tissue.
The blood vessels leak, blood pressure drops, clots form, and catastrophic organ failure can occur.
Several studies have shown that increased levels of cytokines that stimulate inflammation are present in the blood of Covid-19 patients.
"The true morbidity and mortality of this disease may be driven by a disproportionate inflammatory response to this virus," said Jamie Garfield, a pulmonologist who treats Covid-19 patients at Temple University Hospital.
However, others do not believe this.
"There seems to be a quick step to link Covid-19 with this hyperinflammatory condition."I haven't really seen convincing data that that's what happened," said Joseph Levitt, a pulmonary critical care doctor at Stanford University's School of Medicine.
He also worried that efforts to reduce the cytokine response could backfire.several drugs target specific cytokines in clinical trials in Covid-19 patients.
However, Levitt worried that the drugs could suppress the immune response needed by the body to fight the virus.
"There is a real risk that we are allowing more virus replication," Levitt said.
Meanwhile, other scientists focus on organ systems that encourage the rapid decline of some patients, such as the heart and blood vessels.
Heart attacking
A 53-year-old woman in Brescia, Italy was taken to a local hospital emergency room with all the classic symptoms of a heart attack, including signs on her electrocardiogram and high blood markers showing damage to the heart muscle.
Further tests showed swelling and scarring of the heart and left ventricle, usually the heart's powerhouse, was so weak that it could only pump one third of the normal amount of blood.
However, when doctors injected a dye into the coronary arteries, looking for a blockage that signaled a heart attack, they did not find it.
It remains a mystery how the virus attacks the heart and blood vessels, but some data prove that damage like this is common.
A paper in JAMA Cardiology, published on March 25, documented heart damage in nearly 20 percent of patients from 416 who were hospitalized for Covid-19 in Wuhan, China.
In another study in Wuhan, it showed 44 percent of 138 patients.the disorder seems to extend to the blood itself.
A matter of blood clotting
According to a journal in Thrombosis Research on April 10, among 184 Covid-19 patients at the Dutch ICU, 38 percent had abnormal blood clots and almost one third already had clots.
Blood clots can rupture and land in the lungs, blocking vital arteries, a condition known as pulmonary embolism, which is reported to have killed a Covid-19 patient.
Clots from the arteries can also enter the brain, causing strokes.
Many patients with high levels of D-dimers, a by-product of blood clots, said a cardiovascular medicine expert at Columbia University Medical Center, Behnood Bikdeli.
"The more we look, the more likely it is that blood clots are a major player in the severity of illness and death from Covid-19," Bikdeli said.
Infection can also cause constriction of blood vessels.reports of ischemia (lack of blood flow) in the fingers and toes, can cause swelling to tissue death.
In the lungs, narrowing of the arteries might help explain anecdotal reports about the puzzling phenomenon seen in pneumonia caused by Covid-19.
Some patients have very low blood oxygen levels and have not been breathing heavily.
It is possible that at some stage of the disease, the virus changes the balance of hormones that help regulate blood pressure and constrict blood vessels to the lungs.
So oxygen uptake is blocked by narrowed blood vessels, not by blocked alveoli.
If Covid-19 targets blood vessels, this can also help explain why patients with damage already present to these vessels, for example from diabetes and high blood pressure, face a higher risk of disease.
The latest Centers for Disease Control and Prevention (CDC) in patients treated in hospitals in 14 US states found that about one third of patients have chronic lung disease, nearly as many have diabetes, and half have high blood pressure.
The fact that there are no asthma sufferers or patients with other respiratory diseases in ICU HUP is one of the surprising things.
Scientists are struggling to understand the causes of cardiovascular damage.
This virus can directly attack the lining of the heart and blood vessels, such as the nose and alveoli, which are rich in ACE2 receptors.
Or maybe lack of oxygen due to chaos in the lungs and damage to blood vessels, or cytokine storms can damage the heart as well as other organs.
"We are still at the beginning."We really don't understand who is vulnerable, why some people are so affected, why it appears so quickly and why it is so difficult (for some) to recover," Krumholz said.
Lack of ventilator
Fear throughout the world of lack of ventilators due to lung failure has received much attention.
"If these people don't die of lung failure, they die of kidney failure," says neurologist Jennifer Frontera of Langone Medical Center, New York University, who has treated thousands of Covid-19 patients.
The hospital is developing a dialysis protocol with different machines to support additional patients.
According to a report, 27 percent of 85 patients treated in hospitals in Wuhan had kidney failure.
Others reported that 59 percent of the nearly 200 Covid-19 patients treated in hospitals around Wuhan had protein and blood in their urine.this indicates kidney damage.
Patients with acute kidney injury are five times more likely to die than Covid-19 patients without these symptoms.
"The lungs are the main battle zone. But a small part of the virus might attack the kidneys.and as in the actual battlefield, if two places are attacked at the same time, each place gets worse, "said Hongbo Jia, a neurologist at the Institute of Biomedical Engineering and Biomedical Technology, Chinese Academy of Sciences.
In a study, virus particles identified in kidney electron micrographs showed a direct virus attack.
However, kidney injury may also be additional damage.
Ventilators increase the risk of kidney damage, as do antiviral drugs including remdesivir, which is being used experimentally in Covid-19 patients.
Cytokine storms can also dramatically reduce blood flow to the kidneys, causing damage that often leads to fatality.
Meanwhile, preexisting diseases such as diabetes can increase the risk of kidney failure.
"There are a number of people who already have some chronic kidney disease who are at higher risk for acute kidney injury," said Suzanne Watnick, chief medical officer at the Northwest Kidney Center.
Brain
Another collection of symptoms that is striking in Covid-19 patients is centered on the brain and central nervous system.
Some people with Covid-19 can lose consciousness and others have a stroke.
Many report losing their sense of smell.
It is still a question whether in some cases, the infection suppresses the brain stem reflexes that feel oxygen starvation.
This is another explanation for the anecdotal observation that some patients are not breathing heavily, even though their blood oxygen levels are very low.
A case study from a Japanese team in the International Journal of Infectious Diseases on April 3, reported traces of a new corona virus in cerebrospinal fluid from Covid-19 patients who developed meningitis and encephalitis, showing that this can also penetrate the central nervous system.
However, other factors can damage the brain, such as cytokine storms that can cause brain swelling and the tendency of blood to clot can trigger a stroke.
The current challenge, moving from conjecture to believing, is when medical personnel focus on saving lives and even neurological assessments such as inducing vomiting reflexes or transporting patients for brain scans at risk of spreading the virus.
Last month, Sherry Chou, a neurologist at the University of Pittsburgh Medical Center, began organizing a worldwide consortium that now includes 50 centers to extract neurological data from treatments that patients have received.
The initial goal was simple: identify the prevalence of neurological complications in patients hospitalized and record how this happened.
For the long term, Chou and his colleagues hope to collect scans, laboratory tests, and other data to better understand the effects of the virus on the nervous system, including the brain.
Chou speculated about the possible invasion route, namely through the nose, then up and through the olfactory bulb, explaining reports of loss of smell connecting to the brain.
"That's a theory that sounds good.we have to really prove it, "he said.
According to a paper in The American Journal of Gastroenterology (AJG), in early March there was a 71-year-old Michigan woman returning from a cruise of the Nile with bloody diarrhea, vomiting, and stomach pain.
Initially doctors suspected he was suffering from an ordinary stomachache, such as salmonella.but after he suffered a cough, the doctor took a nasal swab and found positive results for the new corona virus.
Stool samples showing positive results for viral RNA, as well as signs of intestinal injury seen in endoscopy, point to gastrointestinal (GI) infection with corona virus.
This case adds evidence to show that the new corona virus, can infect the lower gastrointestinal lining, where ACE2 receptors are abundant.
Viral RNA has been found in as many as 53 percent of patients' fecal samples and in a paper published in Gastroenterology, a Chinese team reported finding a protein shell virus in gastric, duodenal, and rectal cells in biopsies from Covid-19 patients.
"I think it might mimic in the digestive tract," said Mary Estes, a virologist at Baylor College of Medicine.
Brennan Spiegel of Cedars-Sinai Medical Center in Los Angeles, co-editor-in-chief of AJG, said the latest report showed that up to half of patients, on average about 20 percent in all studies, had diarrhea.
GI symptoms are not on the CDC-19 list of Covid-symptoms, which can cause some cases of Covid-19 to go undetected.
The presence of a virus in the GI tract increases the likelihood of discomfort that can be transmitted through feces.but it is not yet clear whether feces containing viruses can be directly infected, not just RNA and protein.
So there is currently no evidence to suggest this.
The CDC says, based on experience from SARS and MERS, the risk of transmission through feces may be low.
The intestine is not the end of a disease journey through the body.
Further research is needed to sharpen the picture of the extent of damage by this virus.