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I'm a Doctor and These COVID Symptoms Alarm Me

COVID expert explains the long-term effects the virus can have.
FACT CHECKED BY Emilia Paluszek

Although COVID cases are declining and the surge is pretty much over, the virus is still very present and causing serious long-term effects for millions of people. Even for people who have experienced a mild case of COVID, they are at risk for severe health issues like heart damage, according to Dr. William Haseltine, a scientist who has worked on the forefront of medical research with cancer and AIDS, an internationally recognized expert on COVID, Harvard professor and author who spoke with Eat This, Not That! Health. Read below to find out the symptoms that are causing lifelong problems and what Dr. Haseltine believes people should know about the virus–and to ensure your health and the health of others, don't miss these Sure Signs You've Already Had COVID.


Why Do Some People Experience COVID More Severely Than Others?

Woman being sick having flu lying on sofa looking at temperature on thermometer. Sick woman lying in bed with high fever.

Dr. Haseltine explains, "The answer has to do with either their age or underlying health conditions. The older you are the more likely you are to suffer serious consequences. The reason for that is because the older you are the weaker your immune system, both your innate and adaptive immune system. Then, there are also predisposing conditions – any immunological disorder, cancer treatments, morbid obesity, diabetes, and obstructive pulmonary disorders and a few others but those are the main ones."


How Long Do Lingering Symptoms Last?

Man having a chest pain and wearing a protection mask.

Dr. Haseltine says, "They have lasted as long as we can measure them now from the very first people that contracted COVID. There are some people who have lingering symptoms for more than three years, and there is some permanent damage that can be done to several critical systems, particularly the heart."


Brain Fog and Fatigue

Woman suffering from headache, holding head with hand while sitting in dinning room at table.

According to Dr. Haseltine, "Some other people experience some very long-term brain fog, or mental dysfunction, that is sometimes so serious that they can't work. The most common long-term symptom is fatigue, and in some cases, the fatigue is so serious that they can't work.  The overall phenomenon we call Long COVID or post-acute PASC."


Serious Heart Disease

heart disease

"SARS-CoV-2 infections can damage heart muscle and affect heart function," says Dr. Haseltine. "There are several reasons for this. The cells in the heart have angiotensin-converting enzyme-2 (ACE-2) receptors where the coronavirus attaches before entering cells. Heart damage can also be due to high levels of inflammation circulating in the body. As the body's immune system fights off the virus, the inflammatory process can damage some healthy tissues, including the heart. SARS-CoV-2 infection can also affect the inner surfaces of veins and arteries, which can cause blood vessel inflammation, damage to very small vessels, and blood clots, all of which can compromise blood flow to the heart or other parts of the body."


Millions of Americans Are Expected to Have Serious Heart Issues Due to COVID

cardiac disease risk

Dr. Haseltine reveals that the, "Most recent data from the US Department of Veterans Affairs on a very large number of people suggests that the serious cardiac symptoms affect 45 people out of 1,000 for a year or more, regardless of age, vaccination status and severity of disease when they caught it. Because there are estimates now of 140 million Americans, that means there are something like 6.3 million Americans are likely to have right now serious heart conditions for over a year. It is going to be a major problem for our health system and for people. And when I talk about major heart conditions, I mean heart attacks and other serious issues." 

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Woman is testing herself for diabetes.

"SARS-CoV-2 infections may raise the risk of developing diabetes, because the virus can damage insulin-producing cells in the pancreas," states Dr. Haseltine. 

Harvard Health reports, "Experts have found that the virus that causes COVID-19 can directly attack insulin-producing structures in the pancreas. According to the NIH director's blog, researchers found that the virus, called SARS-CoV-2, affects the pancreas in three different ways. First, it may directly damage pancreatic beta cells, the ones that produce insulin, reducing their ability to make enough insulin to keep blood sugars controlled. Second, as the virus replicates in the pancreas, it also can damage the cells that directly surround the beta cells, which are needed for proper insulin release. Third, the virus also seems to reprogram surviving cells, making them malfunction, which can wreak havoc with blood sugar regulation."

RELATED: The #1 Sign Your Blood Sugar is "Way Too High"


What People Should Know

Doctor examining female patient in critical health conditions using a stethoscope in the intensive care unit of a modern hospital during covid-19 pandemic

Dr. Haseltine explains, "For advice, I think health care systems should do a serious cardiac work up on all patients that have been infected by COVID. Patients should be aware that having COVID, even if it was the mildest of cases, puts them at equal risk for serious heart disease to someone that was in the ICU. It is a risk of about 5% of people, who have had any form of COVID, regardless of vaccination status. It's really confounding. People can't understand how all of this damage can occur to the heart if you've been vaccinated or had even a mild case. Long COVID is a very serious long-term consequence of this disease." 

RELATED: "Weird" COVID Symptoms You've Never Heard Of


How to Stay Safe Out There

Brunette woman wearing a KN95 FPP2 mask.

Follow the public health fundamentals and help end this pandemic, no matter where you live—get vaccinated or boosted ASAP; if you live in an area with low vaccination rates, wear an N95 face mask, don't travel, social distance, avoid large crowds, don't go indoors with people you're not sheltering with (especially in bars), practice good hand hygiene, and to protect your life and the lives of others, don't visit any of these 35 Places You're Most Likely to Catch COVID.

Heather Newgen
Heather Newgen has two decades of experience reporting and writing about health, fitness, entertainment and travel. Heather currently freelances for several publications. Read more about Heather