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COVID-19: The Optum Store Guide

12 minute read
Woman taking a Covid test

Millions of people have been infected with COVID-19. Our guide covers everything you need to know about symptoms, vaccines, tests, treatments and more.

Erin L. Boyle

By Erin L. Boyle

Everyone will have the common cold at some point in their lives. We all know the symptoms: runny nose, sore throat, cough. This type of illness can be caused by a coronavirus.

By now, you’re all too aware of another type of coronavirus as well. It can be mild, but in some cases, it can be much more severe: COVID-19.

COVID-19 was discovered in Wuhan, China, in December 2019. Since then, it’s been responsible for more than 450 million cases around the world (and counting). And more than 6.2 million people around the globe have died from it during the pandemic.

COVID-19 has been a part of life for the past couple of years, even if you haven’t been infected. But now we have COVID-19 vaccines and treatments specifically for the illness. And there is light at the end of the tunnel.

Let’s take a look at COVID-19 in depth. Our guide will explain the basics of what it is, what the symptoms are, how you can treat it and more.

What exactly is COVID-19?

COVID-19 is the respiratory illness (an infectious disease) caused by the SARS-CoV-2 virus. “It ranges in severity from a mild respiratory infection to severe pneumonia that can be fatal,” says Jason Gallagher, PharmD. He’s a clinical professor at Temple University and a clinical pharmacy specialist in infectious diseases at Temple University Hospital in Philadelphia.

“Roughly 80% of unvaccinated people have a mild infection, though the term ‘mild’ is often misunderstood,” he explains. “Clinically, mild means no need for hospitalization or medication. Patients may feel terrible but still be ‘mild.’”

Outcomes for hospitalized patients have improved. But patients who need to go into the intensive care unit still have a high chance of dying. The vast majority of those patients are unvaccinated.

How do you catch COVID-19?

You can get COVID-19 in several basic ways:

  • Airborne transmission: You can catch it by breathing in small virus-containing droplets from an infected person who exhales them near you. Those droplets can live in the air for up to 3 hours after someone exhales them. That is according to research published in The New England Journal of Medicine.
  • Contract transmission: You can get exposed to the virus if you have those droplets on your hands and touch your eyes, nose or mouth. This can happen when you touch an area that a contagious person has just sneezed or coughed on.
  • Droplet transmission: You can catch the virus if your nose, mouth or eyes are exposed to the virus’s droplets. This can happen when someone coughs or sneezes near you.

From at-home tests to at-home care, Optum’s COVID-19 resource center is here for you.

How can you prevent COVID-19?

You can protect yourself (and others) from COVID-19 in a number of ways. The most important way:

  • Getting vaccinated and boosted. Doing so is vital to being all right if you get COVID-19, says William W. Li, MD, an internist in Cambridge, Massachusetts. Dr. Li is the president and medical director of the Angiogenesis Foundation, which is leading research into COVID-19. Getting vaccinated and boosted can reduce your risk for severe disease, hospitalization and death from the virus, according to the Centers for Disease Control and Protection (CDC).

Other ways to prevent COVID-19 include:

  • Wearing a mask. A well-fitting, good-quality mask (surgical mask, KN95 or N95) can help block exposure to virus droplets and particles. Wearing a mask dramatically reduces the chances of infection, Dr. Li says. In early 2022, the CDC reported that wearing a KN95 or N95 lowered the odds of testing positive for COVID-19 by 83%. Wearing a surgical mask lowered the odds by 66%. You should wear a mask if:
    • COVID-19 levels are high in your community
    • You’re sick with COVID-19
    • You’ve just been sick with it and are around others
  • Staying 6 feet away from others. Social distancing can help reduce your risk of catching the virus. That’s because you’re not as close to those who might be exhaling virus droplets.
  • Being outside/having good air filtration. “Socializing in outdoor spaces is another way to reduce risk while COVID-19 is still a pandemic,” Dr. Li says. Having good air circulation both indoors and outdoors can help.
  • Getting tested. If you’re feeling ill with COVID-19 symptoms, testing ASAP can help you determine if you’re sick. That can reduce transmission to your loved ones, because you’ll know that you need to isolate until you’re no longer contagious. And if you’re not experiencing symptoms, you could still be asymptomatic. This means you have the virus but don’t have symptoms.
  • Washing your hands. Make sure to lather them with soap for at least 20 seconds, then rinse with water. Use hand sanitizer if you don’t have soap and water handy.

What are my COVID-19 vaccine options?

Three vaccines are available in the U.S. Two of them use messenger RNA (mRNA) technology. The third is called a viral vector vaccine. Here’s more about each:

Pfizer-BioNTech COVID-19 vaccine. This mRNA vaccine is approved by the U.S. Food and Drug Administration (FDA) for those age 16 or older. It has emergency use authorization for those who are 5 to 15 years old. Key details you should know about the Pfizer vaccine:

  • It’s given as 2 doses, 3 weeks apart. This is called the primary series.
  • Then, if you’re 18 or older, you should have a booster dose 5 months after the last dose in your primary series. If you’re 5 to 17 years old, you should also have a booster 5 months after the last dose of your primary series. But unlike those who are 18 or older, you can receive a booster only from Pfizer-BioNTech.
  • This vaccine does have side effects. These usually appear within 7 days of receiving it. They’re typically mild and can include fever, chills and headache.

Moderna COVID-19 vaccine. This mRNA vaccine is FDA-approved for those age 18 or older. In real-life situations, both mRNA shots cut the risk of serious illness by at least 90%. Key details you should know about the Moderna vaccine:

  • It’s given as 2 doses, 4 weeks apart, which is called the primary series.
  • Then, everyone 18 years and older should have a booster shot 5 months after the last dose of their primary series.
  • Side effects can include fatigue, headaches, and pain and swelling where you got the shot, up to about 7 days afterward.

Johnson & Johnson COVID-19 vaccine. In clinical trials, this viral vector vaccine gave the best coverage 2 weeks after getting it. Key details you should know about the Johnson & Johnson vaccine:

  • It’s given as 1 dose.
  • If you’re 18 or older, you should have a booster dose of either the Pfizer-BioNTech or Moderna vaccine at least 2 months after your first dose of this vaccine.
  • While this vaccine is available in the U.S., officials have recommended the use of the 2 approved mRNA vaccines over this one. That’s because of a rare risk of blood clots.

What are the symptoms of COVID-19?

The most common symptoms of COVID-19 are fever, cough and shortness of breath. Other symptoms include:

  • Fatigue
  • Muscle or body aches
  • Headache
  • New loss of taste or smell
  • Sore throat
  • Congestion or runny nose
  • Nausea or vomiting
  • Diarrhea

Not everyone who gets COVID-19 will have all these symptoms. It’s possible to have only a single symptom, several or even none. Having no symptoms is called being asymptomatic.

If you think you might have COVID-19, our providers are standing by to help. Schedule a virtual appointment as soon as today and get guidance on testing, how to treat your symptoms and when to seek in-person care.


How do you know if you have COVID-19?

You can test for the virus in 2 ways, with a PCR test or an antigen test. Each has its pros and cons.

  • PCR test. The PCR test is considered the gold standard for COVID-19 screening. It is a molecular test and has the highest accuracy rate of any COVID-19 test. It detects the virus’s genetic material, even in small amounts.

You can have PCR testing done at a drive-in clinic, a pharmacy or your doctor’s office. You can also buy take-home PCR kits, but those aren’t as reliable as the ones done by health care professionals.

  • Antigen test. Also called rapid tests, these tests detect proteins made by the immune system to stop COVID-19. Getting your test result (positive or negative) takes 10 to 15 minutes at home. If you have COVID-19 symptoms, test yourself immediately, recommends the CDC. If you were exposed to someone with COVID-19, wait at least 5 days after your exposure to test yourself. (If you test negative, consider testing again 1 to 2 days later.) You can purchase antigen tests in stores or online — and can even receive 4 free ones through the federal government.

“The biggest advantage of rapid antigen tests is that they are a fast, cheap and reliable way for you to find out if you’re spreading the virus,” says Vivek Cherian, MD. He’s a Chicago-based internal medicine physician who has been treating patients with COVID-19 since the start of the pandemic.

“A PCR test is more sensitive and can actually identify an infection sooner, but the downside is that it can take a few days to get your results,” says Dr. Cherian. Both tests can be useful. But the benefit of a rapid test is that it can prompt you to isolate sooner. This prevents you from spreading the virus earlier.

(Stock up now on COVID-19 home tests. Start shopping.)

What should I do if I have COVID-19?

Stay home if you test positive for COVID-19. Rest and take over-the-counter medications as needed. Keep in touch with your doctor — especially if you’re at high risk of severe illness from COVID-19 (more on that below). Seek emergency medical care right away if you have:

  • Trouble breathing
  • Pain or pressure in your chest
  • Confusion
  • Difficulty waking up and staying awake

You might be wondering about quarantining and isolating. You quarantine from other people if you were exposed to a disease but aren’t (yet) sick. This helps you avoid possibly exposing others. You isolate from others when you are sick or test positive, to avoid exposing them.


When should I quarantine?

Here’s when to quarantine (or not) for COVID-19, according to the CDC:

If you were exposed but you’re not fully vaccinated and boosted: You need to quarantine. You should:

  • Quarantine for at least 5 days, if possible, after the day you were exposed.
  • Get tested, even if you don’t have symptoms, at least 5 days after exposure.
  • Use a well-fitting mask when you’re around others, even at home, for 10 days after exposure. Wearing a mask is especially important if you can’t quarantine.
  • Avoid traveling for 10 days.
  • Avoid those who are at risk of serious COVID-19 illness, if you can.
  • Watch for symptoms until 10 days after exposure. If you develop symptoms, isolate right away and test.

If you were exposed but are fully vaccinated and boosted: You don’t have to quarantine unless you have symptoms. You should:

  • Take a COVID-19 test at least 5 days after exposure so that the virus will show up on testing. Do so even if you don’t have symptoms.
  • Watch for symptoms for 10 days after exposure, and wear a mask around others for 10 days.
  • Avoid people who are at high risk of serious COVID-19 illness, if possible. If you do develop symptoms, isolate ASAP and test.

If you were exposed but had COVID-19 within the past 3 months: You don’t need to quarantine unless you have symptoms. You should:

  • Watch for symptoms for up to 10 days.
  • Wear a mask during that time, avoid high risk people and isolate/test if you get sick.
  • Know that it is possible to be reinfected with COVID-19.

When should I isolate?

It doesn’t matter whether you’re fully vaccinated and boosted or if you’re unvaccinated. When you test positive for COVID-19, you should:

  • Stay home for a full 5 days after a positive test/start of symptoms, and isolate from others.
  • Wear a well-fitting mask around people for 10 days after a positive test/start of symptoms.
  • If you don’t have symptoms but do have a positive test result, you can end isolation after 5 full days.
  • If you have symptoms, you can end isolation after 5 full days if you haven’t had a fever for 24 hours (without fever-reducing medications) and your symptoms are improving.

If COVID-19 made you very sick or you’re immunocompromised, you need to isolate for at least 10 days. Talk to your doctor before ending isolation.

Try to protect people who are at high risk of bad COVID-19 outcomes by staying away from them while you’re sick.

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Who is most at risk for severe COVID-19?

Anyone can get really sick from the virus. But certain factors raise the risk of severe illness. They also increase the chance that you will be hospitalized, need intensive care, require a ventilator or even die. Those factors are:

  • Age (being 65 and older)
  • Cancer
  • Certain disabilities
  • Chronic kidney disease
  • Chronic liver disease
  • Chronic lung diseases (such as moderate to severe asthma and chronic obstructive pulmonary disease, or COPD)
  • Cystic fibrosis
  • Dementia
  • Diabetes (types 1 and 2)
  • Heart conditions
  • HIV infection
  • Immunocompromised state
  • Mental health conditions
  • Overweight and obesity
  • Pregnancy
  • Sickle cell disease or thalassemia
  • Smoking (current or having quit)
  • Solid organ or blood stem cell transplant
  • Stroke or cerebrovascular disease
  • Substance use disorders

What are the available treatments for COVID-19?

At first, there were no medications approved to treat the virus specifically, Dr. Li points out. Many people with mild symptoms used over-the-counter medications such as acetaminophen (Tylenol®) to reduce fever and headache. But now doctors have a wider range of medications to choose from:

  • Antiviral medications. Two COVID-19 antiviral medications received emergency use authorization in late 2021. Legevrio® (molnupiravir) and Paxlovid® (nirmatrelvir/ritonavir), are now on the market. They can be used to treat mild-to-moderate COVID-19. Paxlovid can be used by people age 12 or older. Molnupiravir can be used by those age 18 or older. They’re available only by prescription.

Another antiviral, Veklury® (remdesivir), was not created to treat COVID-19 specifically. But it has helped hospitalized patients get better.

  • Monoclonal antibodies. Bebtelovimab appears to be effective against the current Omicron BA.2 sub-variant strain (the dominant strain as of May 2022).
  • Immunomodulators. Actemra® (tocilizumab) can help patients with severe COVID-19, especially when used with the corticosteroid dexamethasone.
  • Corticosteroids. Dexamethasone (multiple brand names) can relieve inflammation. It has shown good results in reducing death in hospitalized COVID-19 patients.
  • Convalescent blood plasma therapy. Plasma antibodies from recovered COVID-19 patients have shown mixed results. They were particularly helpful earlier in the pandemic before newer treatments became available. They’re now authorized for use in patients with compromised immune systems.

Our expert panel

Jason Gallagher, PharmD
Clinical pharmacy specialist in infectious diseases at Temple University Hospital and director of the PGY2 Residency in Infectious Diseases Pharmacy at Temple University, Philadelphia

William W. Li, MD
Internist and author of Eat to Beat Disease: The New Science of How Your Body Can Heal Itself; CEO and medical director of the Angiogenesis Foundation in Cambridge, Massachusetts

Vivek Cherian, MD
Internal medicine physician, Chicago

Additional sources 

COVID-19 case numbers: Johns Hopkins University of Medicine Coronavirus Resource Center (2022). “COVID-19 Dashboard”
Airborne transmission research: The New England Journal of Medicine (2020). “Aerosol and surface stability of SARS-CoV-2 as compared with SARS-CoV-1” 
COVID-19 basics: Centers for Disease Control and Prevention (2022). COVID-19: “Frequently Asked Questions”
Prevention: Centers for Disease Control and Prevention (2022). “COVID-19: How to Protect Yourself & Others”
Vaccines: Centers for Disease Control and Prevention (2022). "Stay Up to Date with Your COVID-19 Vaccines"
Treatments: Johns Hopkins Medicine (2022). “Is COVID-19 Treatable?”