We still don’t know how the new coronavirus kills us

Fever, cough and shortness of breath are the main symptoms of coronavirus. Or not, or more or less: one study found that seven out of 10 people who needed to be hospitalized he had no fever and another established that three out of 10 did not cough and the range of those who were not short of breath ranged from six and nine out of 10. And yet all the patients in those investigations were so sick of COVID-19 —Even if they did not present fever, cough or shortness of breath— that they needed to be admitted to hospital.

More serious still, there symptoms not usually associated with the disease that causes SARS-CoV-2, how cerebrovascular accident (ACV) or toxic shock syndrome and that, however, they have appeared in some cases, repeatedly enough to attract attention and enter the set of factors that doctors should consider as a signal.

TO almost six months from the beginning of the pandemic, with more than three million infected people in the world and more than 215,000 deaths, one global economic crisis unprecedented and measures social distancing With a high psychic cost, the coronavirus becomes more and more mercurial every day. Politicians try different ways of reopening in the hardest hit countries like Spain and the United States, with such disparate criteria that infectologists are concerned for fear of a second wave of contagions, but scientists are no longer certain.

“At the beginning of the epidemic, it was believed that the coronavirus was a variant of a known disease family, not a mysterious evil, although it is infectious and worrisome “, recalled the magazine New York. But the profile of a predictable respiratory disease “becomes less clear every week” The publication quoted Carl Zimmer, a prestigious journalist specializing in science in the United States, who tweeted “Virologists, is there in the world some other virus that’s that weird As for its range of symptoms? “

According to the clinical and treatment guidelines that the Hospital Brigham and Women’s from Boston, linked to Harvard University, compile and adjust in real time, the range of fever in patients with symptoms of COVID-19 it ranges between 44% and 94%, that of cough between 68% and 83% and that of shortness of breath, between 11% and 40%, with other secondary ones such as nausea and diarrhea (3% to 17%), confusion (9%) and headache (8% to 14%). “The very fact that the ranges are so wide indicates that the disease occurs very different ways in different hospitals and patient populations, leading some doctors and scientists to theorize that the virus could attack the immune system as the HIV, while many others consider that the disease triggers a kind of opposite response, a overreaction of the immune system”, Synthesized the medium.

The greatest confusion that the disease has presented so far lies precisely in what seemed to be the target of SARS-CoV-2, the respiratory system.

In general, what happens when a virus attacks lung function and blood oxygen levels is highly predictable. “But for weeks now, doctors on the front line have been confused because many patients with coronaviruses had lethal low blood oxygen levels, while, according to the most common indicators, they seemed to be fine”, Presented New York. “It is one of the reasons why they began to reevaluate the initial clinical focus in respirators, which are generally recommended when patients’ oxygenation drops below a certain level, but after weeks they seemed to questionable benefit for COVID-19 patientsThey could have evolved better with milder or different forms of oxygen supplementation. “

In fact, the 88% of the patients who required a ventilator in New York died. A figure similar to China’s experience, 86 percent.

Richard Levitan, an emergency physician, wrote in The New York Times a possible explanation for the phenomenon of apparently stable patients who nevertheless have deadly low blood oxygen levels: the silent hypoxia, what happens when alveoli collapse, not when they harden or fill with fluids what happens in pneumonia. His work was based on the experience he had in the hospital Bellevue, but to verify that this is a behavior of the SARS-CoV-2, a general study is required.

Li Lanjuan, researcher at the University of Zhejiang, China, published a preliminary essay in which he argued that the ability to mutate who has this new disease. From the analysis of 11 patients, Li and his colleagues found 30 mutations. “The More aggressive strains could generate viral loads up to 270 times larger than the weaker strains “, synthesized the South China Morning-Post. “They were also the ones that destroyed cells the fastest.”

Another theory points to how the coronavirus affects the blood: it creates clots. The Washington Post reported that the key was discovered when studying fatal victims of COVID-19: “The autopsies have shown that some people’s lungs fill with hundreds of micro clots. The larger ones can be detach and travel to the brain or heart, and cause a stroke or heart attack. “

The article also noted that in the month that the United States became the epicenter of the pandemic, doctors “have become increasingly convinced that the COVID-19 attacks not only the lungs but also the kidneys, heart, intestines, liver, and brain” A list that matches your analysis Science: “Despite the more than 1,000 studies that reach academic publications every week, the appearance of a clear image remains elusive, since the virus acts like no other pathogen known to mankind” In one illustration, the science journal summarized the areas affected by the coronavirus that have been documented: “Brain, eyes, nose, lungs, heart, blood vessels, liver, kidneys, intestines. “

New York gathered some of the evidence: “In Wuhan it was discovered heart damage in 20% of hospitalized patients, and 44% of those in intensive care had arrhythmias; 38% of Dutch intensive care patients showed a irregular coagulation; 27% of Wuhan patients had renal insufficiency, and many more revealed signs of kidney damage; half of chinese patients showed Hepatic injury and, according to studies, between 20% and 50% of patients had diarrhea“

The Post also reported that young and middle-aged adults, “Just sick with COVID-19, they die of ACV ”. Some they didn’t even know they were infected, as described by a medical history that was not of great interest to the naked eye: “I did not take medications, I had no history of chronic diseases. He had felt good, spending time at home like the rest of the country, when suddenly she had trouble speaking and moving the right side of her body. The images showed a blockage in the left cerebral hemisphere. “Everything would have been typical of a cardiovascular problem if it wasn’t for the man having 44 years —The average age for these episodes is 74— and had given positive in the SARS-CoV-2 swab.

Something stranger was seen when doing the intervention to remove the clot: the doctors observed how, while pushing it, new clots formed around it. “These LCAs could explain the large number of patients who die at home, several doctors theorized, many or most of whom die suddenly, “New York continued.” According to Brigham and Women’s Hospital guidelines, only 53% of COVID-19 patients died. only due to respiratory failure“

In a few months he went from believing that there was no asymptomatic transmission to consider that at least half of the infections probably show no symptoms, to believe that the face masks they were useless to impose their use in public, to believe that the young boys they did not get sick to estimate that they were a little less vulnerable. All this, the magazine concluded, means that the new coronavirus has caused not only one public health crisisbut also acscientific laugh. And for none is there an obvious way out.