COVID-19: Causes, Symptoms, Treatment & Prevention

COVID-19 (the 2019 novel coronavirus) is the respiratory illness that’s led to an unprecedented global pandemic, with more than 78 million cases and 1.7 million deaths around the world as of December 2020. In the United States alone, the Centers for Disease Control and Prevention (CDC) reports more than 18 million U.S. cases and 321,000 deaths in the U.S. as of December 2020.

The coronavirus pandemic has been widely described as a public health emergency. Public health officials recommend that people take precautions such as wearing face coverings, avoiding unnecessary travel, and social distancing. Across the globe, scientists, physicians, and public health officials have been racing to learn more about this novel coronavirus, slow the spread of new COVID-19 cases, and develop treatments and vaccines to save lives.

What Is COVID-19?

COVID-19 is a respiratory illness caused by a virus in the coronavirus family. Compared to other coronaviruses, it can be more severe and spreads more easily. Because it’s the first time that this particular coronavirus strain has been discovered, it’s referred to as a novel (or new) coronavirus.

Most people who contract COVID-19 have mild symptoms and get better without significant medical care. Some people have no symptoms at all. However, roughly 1 in 6 people have more serious symptoms, including shortness of breath, difficulty breathing, and other health complications. These are especially likely for older populations or those with pre-existing health conditions such as diabetes or heart disease.

Due to how easily COVID-19 spreads and how severe it can be for vulnerable populations, there has been a global effort to control the outbreak.

What Are COVID-19 Symptoms?

Signs and symptoms typically appear two to 14 days after exposure. The most common signs and symptoms include:

  • Fever
  • Cough
  • Tiredness

Early symptoms may also include a loss of taste or smell.

Because symptoms day-by-day can vary, additional common symptoms may include:

  • Shortness of breath
  • Difficulty breathing
  • Headaches
  • Muscle aches
  • Chest pain
  • Sore throat
  • Runny nose
  • Chills
  • Pink eye (conjunctivitis)
Elderly woman walking outside without a mask

Other less common symptoms can also include rashes, nausea, vomiting, or diarrhea. The severity of symptoms can range from very mild to severe. More serious complications include:

  • Pneumonia and trouble breathing
  • Acute respiratory distress syndrome
  • Heart problems
  • Blood clots
  • Acute kidney injury
  • Organ failure
  • Additional viral and bacterial infections

Severe symptoms or complications are more likely to occur in older people or those with other pre-existing health conditions. Health conditions that increase the likelihood of serious illness from COVID-19 can include:

  • Heart disease
  • Cancer
  • Chronic obstructive pulmonary disease (COPD)
  • Type 1 diabetes
  • Type 2 diabetes
  • Obesity or severe obesity
  • Smoking
  • Chronic kidney disease
  • Sickle cell disease
  • Weakened immune system from organ transplants, HIV or some medications
  • Asthma
  • Liver disease
  • Chronic lung diseases such as cystic fibrosis or pulmonary fibrosis
  • Brain and nervous system conditions
  • High blood pressure

However, this list is not all-inclusive, as other underlying health issues can increase the risk of serious illness and complications.

Emergency Symptoms

Call a doctor or hospital immediately if you experience one or more of these symptoms:

  • Trouble breathing
  • Constant pain or pressure in your chest
  • Bluish lips or face
  • Sudden confusion

Make sure to let your doctor’s office or hospital know before you visit, so they can prepare to treat you while protecting other patients and medical staff from contracting COVID-19.

COVID-19 in Children

While children generally have similar COVID-19 symptoms as adults, symptoms of the illness are often milder. The American Academy of Pediatrics reports more than 850,000 children testing positive for COVID-19 as of October 2020, with 0.00% – 0.18% of cases resulting in deaths among children. Symptoms in children generally include:

  • Fever (reported in around 56% of children)
  • Cough (reported in around 54% of children)
  • Shortness of breath (reported in around 13% of children)

Some children and teens experience a syndrome from COVID-19 called pediatric multisystem inflammatory syndrome (PMIS). Symptoms of PMIS include fever, rash, vomiting, belly pain, heart problems, and diarrhea. Researchers suspect that this syndrome is similar to toxic shock or Kawasaki disease, a condition causing inflammation in the blood vessels of children.

Father putting mask on son as family goes outside

What Causes COVID-19?

While federal agencies, scientists, and health care workers continue to discover new data about how COVID-19 spreads, the latest research shows that spread mainly occurs among those in close contact—defined as roughly 6 feet or 2 meters. When someone infected sneezes, coughs or talks, the virus can spread via respiratory droplets which can then land in the nose, eyes or mouth of someone nearby, thus spreading infection.

Researchers also believe that people can be infected with COVID-19 if they touch a surface or object with the virus on it, and then touch their nose, eyes or mouth. The amount of time that the virus can live on objects is unknown. Experts estimate that it ranges from a few hours to nine days, depending on the type of surface, temperature and environment. It seems that spread can also occur when someone is exposed to small droplets or aerosols that contain the virus in the air. However, neither of these methods—objects or aerosols—are considered to be the main way COVID-19 spreads.

How Does COVID-19 Compare to the Flu?

COVID-19 is similar to the flu (influenza) in that both are contagious respiratory viruses that are caused by viruses, and both share common symptoms. However, there are many differences between COVID-19 and influenza, such as how the viruses spread and its severity. Influenza has also been studied for much longer than the COVID-19, so doctors know more about treating and preventing influenza.

Similarities Between COVID-19 and the Flu

The first way in which COVID-19 and the flu are similar is in their symptoms. Both can cause:

  • Fever
  • Tiredness
  • Cough
  • Shortness of breath
  • Difficulty breathing
  • Sore throat
  • Runny or stuffy nose
  • Headache
  • Muscle aches
  • Nausea or vomiting (more common in children than in adults)

Both viruses range from no symptoms to mild or severe symptoms. Many people recover at home from either virus with rest and fluids. However, either virus can lead to more serious complications that require hospital care, such as pneumonia, stroke, heart attacks, organ failure, heart or brain inflammation or acute respiratory distress syndrome.

Because the symptoms are so similar between COVID-19 and the flu, it can be hard to diagnose which illness you have—especially during flu season. It’s best to arrange for COVID-19 testing and flu testing if you suspect you’ve been infected. More on that below.

Another similarity between COVID-19 and the flu is how the viruses spread. Both viruses spread between people who are in close proximity, and both viruses spread through respiratory droplets or aerosols from talking, coughing or sneezing. The viruses also potentially spread when someone touches a surface containing the virus, then touches his or her nose, mouth or eyes.

Medical professional discussing COVID-19 with elderly person

Differences Between COVID-19 and the Flu

While COVID-19 and the flu share similarities, there are also many differences.

  • Viruses. Completely different viruses cause COVID-19 and influenza. Influenza is caused by influenza A and B viruses, while COVID-19 is caused by SARS-CoV-2. Much is known about influenza A and B since researchers have been studying these viruses for several decades, while SARS-CoV-2 was newly identified in 2019 so there is still much to learn.
  • Symptoms. As noted above, there is some overlap in symptoms between the flu and COVID-19. However, flu symptoms generally appear around one to four days after exposure, while COVID-19 symptoms typically appear two to 14 days after exposure.
  • Contagiousness. COVID-19 appears to be spread more easily than the flu. Researchers estimate it’s more contagious than the flu but less contagious than measles.
  • Severity. COVID-19 appears to lead to serious illness more commonly than the flu.
  • Treatment. Another major difference between COVID-19 and the flu is that physicians can treat influenza with antiviral drugs. However, no antiviral drugs are currently approved for treatment with COVID-19, although some drugs may help reduce its severity. Researchers are currently evaluating many treatments for COVID-19 spanning drugs to a COVID-19 vaccine. With influenza, you may get an annual flu vaccine to help reduce the risk of contracting the flu as well as its severity. This flu vaccine is designed to protect against three or four of the year’s most common influenza viruses. However, the flu vaccine does not protect against COVID-19. Pfizer recently announced a COVID-19 vaccine, with early data showing it’s 90% effective in preventing COVID-19 in participants without evidence of prior SARS-CoV-2 infection.  

How Do You Prevent COVID-19?

Although there is no widely available COVID-19 vaccine yet, there are steps you can take to prevent contracting the virus. The World Health Organization (WHO) and Centers for Disease Control and Prevention (CDC) recommend:

  • Washing your hands regularly. Use soap and warm water and wash for at least 20 seconds. When unable to wash your hands, you may alternatively use an alcohol-based hand sanitizer containing at least 60% alcohol.
  • Avoiding touching your face. If you touch a surface containing the virus, avoid touching your mouth, nose and eyes to help prevent infection.
  • Coughing and sneezing into your elbow. You may alternatively cough or sneeze into a tissue, but throw away the tissue and wash your hands right away.
  • Avoiding crowds and practicing social distancing. Keep a distance of around 6 feet between people outside of your household. Keep in mind that many people who have COVID-19 show no symptoms but can still spread the virus.
  • Avoiding anyone who is sick or has symptoms. If you have a chronic medical condition or weakened immune system, it’s especially important to avoid those infected with COVID-19 due to the more severe health risks it could pose for you.
  • Staying at home if you’re sick. Avoid public areas unless you’re traveling to get medical care. Even then, avoid public transportation, taxis and ride-sharing if possible. Also avoid sharing dishes, towels, bedding and other household items if you’re sick.
  • Cleaning high-touch surfaces often. Disinfect high-touch surfaces such as doorknobs, light switches, electronics and counters daily with cleaners made of at least 60% alcohol.
  • Cover your nose and mouth with a face mask. The CDC recommends that people wear a cloth face mask in public areas such as grocery stores or public transportation. A face mask is not intended to protect the wearer, but may reduce the spread of the virus from the wearer to other people. N95 respirators should be reserved for health care providers.
  • Reduce unnecessary travel. If you’re planning to travel outside of your usual routine, check the WHO and CDC websites for updates and advice. Take extra precautions such as wearing a face mask, washing your hands frequently, and packing hand sanitizer.
Factory worker wearing a mask to protect from COVID-19

What Do You Do if You Suspect You Have COVID-19?

If you suspect that you have COVID-19 or are showing any signs and symptoms, contact your health care provider immediately. Tell them about any symptoms you are experiencing, whether you have pre-existing health conditions, and whether you’ve been in contact with someone with COVID-19. This will help your health care team determine how you should be evaluated—for both your own safety and that of other patients and health care providers.

What to Do if You Have Mild Symptoms

Because the severity of symptoms ranges, some cases will be mild to moderate and will not require hospital care. If you think you’ve come into contact with the virus, or if you have symptoms, take the following precautions.

  • Get tested as soon as possible. This enables you to notify friends and family members (contact tracing), address symptoms as best as you can, and look out for worsening symptoms. When you get tested, it’s important to go to a facility that has proper safety measures in place and allows for as much social distancing and mitigation as possible.
  • Isolate yourself. Try to avoid contact with other people—even in your household—to prevent them from getting sick. Designate a room or part of your home where you can recover. Use a separate bathroom if possible. Wear face masks when around others.
  • Monitor your temperature. Check your temperature every morning and evening for at least 14 days. Keep track of the readings. A fever is one of the most common symptoms of COVID-19.
  • Rest and drink plenty of fluids. Take time to recover as you would another virus.
  • Keep track of your symptoms. If they get worse, seek medical care.
  • Tell your doctor about your illness. While hospital care won’t be necessary for the vast majority of people, your doctor has a more complete picture of your health and will be able to provide guidance on the best course of treatment.

What to Do if You Have Emergency Symptoms

The following are considered emergency COVID symptoms. If you experience any of these signs or symptoms, contact your health care provider immediately.

  • Persistent chest pain or pressure
  • Inability to stay awake
  • Trouble breathing
  • New confusion
  • Blue lips or face

How Do You Get Tested for COVID-19?

Testing is an important part of limiting the spread of COVID-19. Not only do tests help people identify whether or not to self-isolate and protect others if they are diagnosed with COVID-19, but they help researchers monitor the global spread and direct resources where necessary.

Handling tests samples for COVID-19

Types of COVID-19 Testing

There are currently two main types of COVID-19 tests.

  • A diagnostic test that tells you if you have a current infection.
  • An antibody test that tells you if you had a previous infection.

Diagnostic Swab Test

Diagnostic swab tests determine whether you have an active COVID-19 infection. These tests are typically administered via nasal or oral swabs at drive-through collection sites. A positive result means it’s very likely that you’ve contracted COVID-19. You should self-isolate and recover with rest and fluids, and contact your health care provider if symptoms worsen. You should get a diagnostic test if you have symptoms or suspect you could have COVID-19.

Antibody Test

Antibody COVID-19 tests determine previous infections. Antibody tests are usually administered through a blood draw or finger prick at a medical facility or lab center. A positive result indicates that you’ve developed antibodies against the virus, but a positive result does not guarantee against reinfection. You should get an antibody test if you suspect you had COVID-19 and want confirmation.

Where to Get Tested

To get a test, locate same day COVID-19 testing near you.

What Are the Long-Term Effects if You Get Sick?

Most people who contract COVID-19 recover fully within a few weeks. However, some people continue to experience symptoms after their initial recovery, even if they had mild symptoms to begin with. Older people and those with several other medical conditions are the most likely to experience persistent symptoms, which may include:

  • Shortness of breath
  • Joint pain
  • Fatigue
  • Cough
  • Headache

Although COVID-19 is considered a respiratory illness, it can affect many other organs. The main organs showing damage related to COVID-19 include:

  • Lungs. The type of pneumonia associated with COVID-19 can damage the tiny air sacs (alveoli) in the lungs, which can lead to scar tissue and long-term breathing issues.
  • Heart. Some imaging tests taken months after COVID-19 recovery show damage to the heart muscle, even in people with mild symptoms. COVID-19 is believed to contribute to small clots that block the smallest blood vessels (the capillaries) in the heart muscle. It’s unclear whether this could increase the risk of heart failure or heart complications in the future.
  • Brain. Even in younger people, COVID-19 has been shown to rarely cause strokes, seizures and Guillain-Barre syndrome, a condition that causes temporary paralysis.
  • Liver and kidneys. COVID-19 can also weaken blood vessels, contributing to potentially long-term issues with the liver and kidneys.

Much is still being uncovered about COVID-19, including its long-term health effects. These potential health issues underscore the importance of taking precautions now, including practicing social distancing, wearing face coverings in public, and practicing good hygiene.

More Resources

For more COVID-19 resources and new updates, visit:

Curative Inc. and its subsidiary, Curative Management Services LLC, engage with medical entities that provide vaccination services.

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