Seizures, kidney failure and respiratory problems are just a few of the symptoms witnessed by physician Joshua Denson during his recent rounds at an intensive care unit. A few days later, he watched as a young woman failed to be resuscitated by his team. Denton, a critical care and pulmonary physician from the Tulane University School of Medicine, shares that these cases all share one striking similarity: “They are all COVID positive.”
Across the globe, the number of confirmed COVID-19 cases has surpassed 2.2 million, with the death toll over 150,000. Pathologists and medical professionals are having trouble comprehending the damage inflicted throughout the body by the coronavirus. What they do know is that the damage from the virus originates in the lungs and can reach other vital organs such as the kidneys, blood vessels, brain, gut and heart.
Harlan Krumholz, a cardiologist at Yale-New Haven Hospital and Yale University, warns that the disease “can attack almost anything in the body with devastating consequences. Its ferocity is breathtaking and humbling.”
Doctors desperately need additional research and knowledge to better treat infected patients as they take a quick turn for the worse. Is blood clotting the reason some healthy patients become seriously ill? Can drugs that are immune-suppressing help in cases where the immune system is overworking? Why are patients not gasping for air when their blood oxygen levels are extremely low? Nilam Mangalmurti, a pulmonary intensivist at the Hospital University of Pennsylvania, says, “Taking a systems approach may be beneficial as we start thinking about therapies.”
Information on how the coronavirus attacks the body’s cells is rapidly evolving, but is truly only scratching the surface in explaining how about 5% of patients are in critical condition. While the virus is often compared to the flu, research is showing that COVID-19 is unlike any virus we’ve seen. Since large-scale studies are just now beginning, scientists are forced to rely on the information from smaller studies that have not been substantiated or reviewed by peers. “We need to keep a very open mind as this phenomenon goes forward,” says physician Nancy Reau, who has been treating patients at Rush University Medical Center. “We are still learning.”
7. How the Infection Begins
COVID-19 (or SARS-CoV-2) is typically transferred from one person to another through the nose and throat. This occurs when an infected person projects droplets that contain the virus and another person breathes in these droplets. According to a report from Wellcome Sanger Institute and other institutions, the virus then adheres to the nose lining. The virus is attracted to tissues with cells that include the angiotensin-converting enzyme 2 (ACE2). The purpose of ACE2 in the body is for blood pressure regulation, and it also acts as a receptor for the virus to access the cell. The virus then takes over the cell, copies itself and infects other cells.
During the first week, infected people begin to release the virus as it multiplies. People may be asymptomatic or they may experience some or all of the six common symptoms, including cough, fever, shortness of breath, headaches, body aches and loss of smell or taste.
At this point, the immune system may win the fight against COVID-19. If not, the virus then heads to the lungs and a fatal attack can begin. The alveoli, small air sacs in the respiratory system of the lungs, contain the vulnerable ACE2 cells. As the cells become infected, this interrupts the transfer of oxygen from the sacs to the capillaries and then the entire body. Chemokines are then released by white blood cells to help with the inflammation. This reaction triggers healthy cells to destroy the virus. The result is pus from the dead cells and an abundance of fluid in the lungs. Patients can recover with assistance from nasal oxygen tubes, while others are not as lucky.
The worst-case scenario is that some patients will develop acute respiratory distress syndrome (ARDS). Breathing becomes incredibly difficult as oxygen levels drop dangerously low. Lungs that have been x-rayed will show cloudy lungs instead of blank space for air. Ventilators are used to help with breathing. A large percentage of patients die as the sacs in the lungs overflow with white blood cells, pus, mucus and fluid.
6. Other Organs at Risk
While we know the potential damage COVID-19 can inflict on the lungs, the virus and the response from the body are clearly hurting other organs as well. Scientists do not know the extent of the damage at this time.
- Brain: Infected patients can experience seizures, confusion, strokes, and inflammation of the brain. It is unknown if these symptoms are directly related to the coronavirus.
- Eyes: Very ill patients commonly have inflammation of the eye and infections such as conjunctivitis.
- Nose: Scientists believe the reason why some patients lose their sense of smell is because the virus damages cells as it passes through the nerve endings.
- Heart and blood vessels: Coronavirus patients are experiencing heart attacks, inflammation and blood clots. The virus is attacking cells along the blood vessels through the ACE2 receptors.
- Liver: Enzyme levels have shown to be high in a large number of hospitalized patients. This indicates that the liver is being damaged as the immune system is overworked, as well as potential side effects from the drugs being used to treat the virus.
- Kidneys: In serious cases, kidney damage is common and deadly. Either the virus directly attacks the kidneys or it is a result of issues such as low blood pressure that affect the entire body.
- Intestines: Cells in the lower gastrointestinal tract are attacked by the virus, as they are high in ACE2 receptors. Diarrhea is present in a small percentage of patients (20%).