The Atlantic – COVID-19 is proving to be a disease of the immune system. This could, in theory, be controlled. “…COVID-19 is, in many ways, proving to be a disease of uncertainty. According to a new study from Italy, some 43 percent of people with the virus have no symptoms. Among those who do develop symptoms, it is common to feel sick in uncomfortable but familiar ways—congestion, fever, aches, and general malaise. Many people start to feel a little bit better. Then, for many, comes a dramatic tipping point. “Some people really fall off the cliff, and we don’t have good predictors of who it’s going to happen to,” Stephen Thomas, the chair of infectious diseases at Upstate University Hospital, told me. Those people will become short of breath, their heart racing and mind detached from reality. They experience organ failure and spend weeks in the ICU, if they survive at all…Half of the patients with COVID-19 who end up in the intensive-care unit at New York–Presbyterian Hospital stay for 20 days, according to Pamela Sutton-Wallace, the regional chief operating officer. (In normal times, the national average is 3.3 days). Many of these patients arrive at the hospital in near-critical condition, with their blood tests showing soaring levels of inflammatory markers. One that seems to be especially predictive of a person’s fate is a protein known as D-dimer. Doctors in Wuhan, China, where the coronavirus outbreak was first reported, have found that a fourfold increase in D-dimer is a strong predictor of mortality, suggesting in a recent paper that the test “could be an early and helpful marker” of who is entering the dangerous phases…”