Understanding COVID-19: A Plain-English Explainer

It still causes many hospital stays each year, mostly among older adults and people with chronic conditions or weakened immune systems, and treatment works best when started early.

Key takeaways

• Stay home and away from others: until symptoms are improving and you have had no fever for 24 hours without fever-reducing medicine
• For the next 5 days: take extra precautions: a mask, distance, hand washing and cleaner air
• Most useful single change: Keep a few FDA-authorized home tests on hand and check their expiration dates.
• Commonest mistake: Going to work, school or gatherings while you still have a fever.
• See a doctor if any of the signs under "When to speak to a doctor" below apply to you.

The short answer

A respiratory illness caused by the SARS-CoV-2 virus, ranging from a mild cold-like illness to severe pneumonia.

Where it fits

This is part of Infectious Diseases. Below: the numbers first, then what to do with them.

The numbers, in one place

What that means in practice

What to do with all of that:

• Keep a few FDA-authorized home tests on hand and check their expiration dates
• Contact your doctor, a pharmacy or a telehealth service quickly after a positive test if you are 65 or older or have a chronic condition
• Rest, drink fluids and use acetaminophen (Tylenol) or ibuprofen for fever and aches as the label directs
• Open windows or use a portable HEPA air cleaner when someone at home is sick

What gets people into trouble

Where people most often come unstuck:

• Going to work, school or gatherings while you still have a fever
• Asking for antibiotics, which do not work against viruses
• Visiting older relatives or someone with a weakened immune system while you are sick

Related topics

• Colds and Flu: What Published Guidance Supports (Immunity)
• The Evidence on Pneumonia, Without the Hype (Respiratory Health)
• The Evidence on Vaccination in Older Adults, Without the Hype (Healthy Aging)
• The Evidence on Adult Vaccination, Without the Hype (Preventive Care)

Where to go next

• What People Get Wrong About COVID-19
• COVID-19 for Beginners: Where to Start
• COVID-19 — the reference entry
• Infectious Diseases: The Complete Guide
• What the Guidance Really Says About Flu Versus a Cold
• Measles: What the Evidence Actually Says

When to speak to a doctor

Contact your doctor if symptoms get worse after starting to improve, or if you are at higher risk and test positive. Call 911 for trouble breathing, persistent chest pain or pressure, new confusion, being unable to wake or stay awake, or pale, gray or blue-colored skin, lips or nail beds.

Where this comes from

• CDC — Respiratory Virus Guidance
• CDC — Treatment of Respiratory Illnesses
• FDA — At-Home COVID-19 Antigen Tests: Take Steps to Reduce Your Risk of False Negative Results

How this page was put together

Every figure, recommendation and warning above is taken from the guidance named in Where this comes from. Nothing on this page is inferred, summarized or generalized beyond what those bodies publish: where they give a number, it is their number, and where they are silent, so are we. Pages are rebuilt whenever the underlying record changes. Sign-off by a named clinician, where it has happened, is shown at the top of the page along with the date.

Medical disclaimer

This article is general information, not medical advice. It cannot account for your own history, medication or circumstances. Always speak to your doctor, pharmacist or another qualified health professional before making changes that affect your treatment, and never delay seeking medical advice because of something you have read here. In an emergency, call 911.