The man, a middle-aged executive, had spent a week on a business trip in China and returned with a fever and cough. He’d gone to an urgent care center and was prescribed antibiotics, but he collapsed at home a few days later and died in the emergency department of the local hospital. I’d been paying close and worried attention to the reports coming out of Wuhan of a novel coronavirus. I hadn’t been told where in China this executive had been, but I did know that a cough and fever were the exact symptoms epidemiologists had identified for the new condition. If this man was going to undergo an autopsy, his body could expose my team and potentially many others to a disease that was, as our overseas medical-worker colleagues were reporting, untreatable, highly contagious, and deadly. I called the U.S. Centers for Disease Control and Prevention (CDC) in Atlanta for support. Two epidemiologists flew in to assist me with the autopsy. I made my discovery as soon as I opened the chest cavity and put my scalpel into an artery of the lungs: a granular, red, spiral glob of coagulated blood that popped right out when I cut across it. It was a pulmonary embolism, a blood clot that had formed in the large vessels of his legs, traveled to his heart, and then lodged in the lungs. The clot blocked blood flow through the lungs, preventing oxygen from reaching the rest of the body. Minutes later, the man was dead. If the executive had died from COVID-19, I’d have expected to see the effects of pneumonia, a viral infection. The lungs would’ve been firm and rough to the touch — but they weren’t. So based on what we all knew at the time, we ruled out COVID-19 as a cause of death and speculated that the man had developed the blood clot after sitting immobile for hours on a transpacific flight. The next week, PCR tests from the CDC confirmed this was not a death from COVID-19. Or was it? After learning more about this virus over the last two years and conducting several autopsies on people who died of blood clots soon after recovering from COVID-19 — now I’m not so sure.

COVID-19 Can Kill in Multiple Ways

We know today that COVID-19 can cause sudden death because the virus has a predilection to attack endothelial cells, which pave the blood vessel highways to all our organs. In the same way that rough roads can result in traffic backups and crashes, damaged endothelial cells can lead to blood clots, which can cause strokes and heart attacks. The body’s first responders, white blood cells, attack the infected endothelial cells, causing more problems: inflamed organs and internal scarring. We’re now learning that the coronavirus targets endothelial cells in every part of the body, causing long-term damage that pathologists like me can see as scars and blood clots in the organs of patients who have died after having recovered from COVID-19. We’re learning, then, that COVID-19 is a multisystem illness in both the acute and long-term phases.

What Long COVID Looks Like From the Inside

In long COVID, which can affect up to 30 percent of those infected, scientists can see the damaging effects of the virus on organs that rely on healthy blood flow. Brain fog? Pathologists put brain tissue under the microscope and see dead nerve cells and inflammatory cells where they shouldn’t be, surrounding blood vessels. Heart palpitations and fainting spells? There could be pale white scars in the red heart muscle, which interrupt signal delivery in its electrical system. Shortness of breath and fatigue? Pink and white patches clog up parts of the lung tissue that should be empty spaces ready to fill with air. Persistent loss of smell? Recent studies have shown that in some people the nerve damage associated with this long COVID symptom is severe and irreversible. COVID-19 can cause permanent damage that affected individuals might carry with them for the rest of their lives. We may find, in the near future, that it’s also shortening their life spans.

What I’m Doing to Stay Safe

I work in New Zealand now. Up until a few weeks ago, there were few deaths from the novel coronavirus, thanks to a successful public health strategy that involved closed borders and coordinated measures like lockdowns, managed isolation, testing, and contact tracing. When the delta variant of COVID-19 finally infiltrated the community in late 2021, New Zealand was already highly vaccinated, and public masking and vaccine passport mandates were in place. The per capita death rate has remained extremely low compared to other countries, despite spikes in infections and hospitalizations with the ongoing omicron wave. So what am I seeing now when I look inside the body of someone who has died with or from COVID-19? The same things we saw at the start of the pandemic in the United States: heart attacks with cardiac rupture and blood clots in the lungs (pulmonary emboli). Some of my patients are even testing negative for COVID-19 at the time of autopsy, yet can be confirmed as having had the disease — because family members report they were exposed, and they had shown positive rapid tests a week before death. That’s why I wonder if I had actually missed a COVID-related death in that very first case I investigated, my Bay Area executive from February 2020. What if he had been exposed to COVID-19 while in China but had recovered, thus testing negative weeks later, when his body came to my morgue for autopsy? What if he had recovered from COVID-19, but the endothelial cell damage caused by the virus eventually caused a blood clot to lodge in his lungs? Excess death data is already showing us that overall mortality has been increasing in countries with rampant spread of COVID-19. There is also data emerging that COVID-19 causes cognitive decline, and that the harm the disease does to the cardiovascular system increases risk of sudden death from strokes and heart attacks within a year of a patient’s infection. What does this mean to us as individuals at a time when politicians are declaring the pandemic over and transglobal corporations are cheering the lifting of mask and vaccine mandates? I can tell you what I’m doing: everything I can to limit repeated exposure to this virus. I am vaccinated and double boosted, and I have vaccinated my children. I’m masking up. I only use N95 masks, and I haven’t eaten indoors with strangers in months. I try to avoid travel as much as possible, and limit my interactions to a small bubble of family and friends. I vote for politicians who have shown they will fund healthcare and support the disabled. I can only control what I do. And here’s what I know as a doctor who does autopsies: A virus that causes permanent organ damage is not worth messing with.