COVID-19 is an infectious disease caused by a new (or novel) coronavirus, SARS-CoV-2, that was first discovered in 2019 and has since killed millions of people around the world. Coronaviruses can produce a range of illnesses, from the common cold to the potentially fatal SARS (severe acute respiratory syndrome).

There currently is no cure for COVID-19, but there are approved and investigational treatments. International groups of scientists have also created COVID-19 vaccines, with three extremely effective ones available in the United States as well as booster shots.

While vaccines are a powerful defense against COVID-19, people can take other precautions as well, such as wearing a face covering in indoor public spaces, washing hands frequently, and social distancing (staying at least six feet away from anyone who is not part of your household).

Signs and Symptoms of COVID-19

Many people with COVID-19 experience symptoms ranging from mild to life-threatening. Symptoms may appear 2 to 14 days after coronavirus exposure, although a significant number of people infected with the virus are asymptomatic, meaning they never develop any symptoms.

According to the Centers for Disease Control and Prevention (CDC), people with these symptoms may have COVID-19:

Fever or chills
Cough
Shortness of breath or difficulty breathing
Fatigue
Muscle or body aches
Headache
New loss of taste or smell
Sore throat
Congestion or runny nose
Nausea or vomiting
Diarrhea

Loss of smell and taste is a common symptom of COVID-19. A study published in October 2020 in PLoS Medicine found that 4 out of 5 people who experienced recent loss of smell or taste tested positive for coronavirus antibodies (proteins produced by the immune system to fight infection), and nearly 40 percent of those did not have the symptoms of cough or fever.

The authors concluded that people who notice that they can’t smell common odors such as garlic and coffee should self-isolate (stay away from other people and pets) and get tested for COVID-19.

Research published in the Journal of Internal Medicine in January 2021 found that 86 percent of people with a mild case of COVID-19 lost their sense of taste and smell compared with only 4 to 7 percent of people with a moderate to severe case of the coronavirus.

Although rashes aren’t on the CDC list, dermatologists have identified a phenomenon called "COVID toes" — red lesions similar to chilblains that can appear on the hands and feet of people who are infected with the virus. A study published June 20, 2020, in the British Journal of Dermatology reported a likely causal relationship between SARS-CoV-2 and COVID toes.

There is still debate in the scientific community whether there is a true association between COVID-19 and chilblains, and more research is needed.

Causes and Risk Factors of COVID-19

COVID-19 mainly spreads by way of respiratory droplets or small airborne particles (aerosols) that are produced when a person coughs, sneezes, or talks. If these coronavirus-laden droplets land in a nearby person’s nose or mouth or are inhaled into the lungs, that person could become infected, according to the CDC.

The CDC says that the risk of transmission is highest within three to six feet of an infected person, but adds, “Although infections through inhalation at distances greater than six feet from an infectious source are less likely than at closer distances, the phenomenon has been repeatedly documented under certain preventable circumstances.” Because of aerosols, indoor environments without good ventilation increase the risk of viral spread.

Respiratory droplets and aerosols can land on surfaces, which means that people may get COVID-19 by touching contaminated objects and then touching their own mouth, nose, or eyes. But the CDC says that the risk of this kind of transmission is low.

Older Adults Are at Higher Risk for COVID-19

Older people who contract COVID-19 are at higher risk for developing a more severe case than younger people. As people age, their immune systems weaken. Older people are also more likely to have chronic conditions that can make it harder for them to recover from COVID-19, according to Johns Hopkins Medicine.

More than 81 percent of COVID-19 deaths occur in people over age 65, says the CDC, adding that the number of deaths among seniors is 65 to 80 times higher than the number of deaths among people ages 18 to 29.

Medical Conditions and COVID-19 Risk

Certain chronic diseases are known to increase the chances a person will have severe illness from COVID-19, leading to hospitalization, the need for a ventilator, or even death. According to the CDC, the conditions that demonstrably increase risk in adults of any age include:

Cancer
Chronic kidney disease
Chronic liver disease
Chronic lung disease, including asthma, COPD (chronic obstructive pulmonary disease), and cystic fibrosis
Dementia and other neurological conditions
Diabetes (type 1 or type 2)
Down syndrome
Heart conditions including heart failure, coronary artery disease, cardiomyopathies (diseases that affect the heart muscle), and possibly hypertension (high blood pressure)
HIV infection
Immunocompromised state (weakened immune system)
Mental health conditions, such as depression and schizophrenia
Obesity and overweight
Pregnancy
Sickle cell disease or thalassemia
Smoking, either presently or in the past
Solid organ or blood stem cell transplant
Stroke or cerebrovascular disease
Substance use disorders
Tuberculosis

Many people have multiple underlying conditions, such as obesity and diabetes. The more underlying conditions a person has, the higher their risk of severe COVID-19.

While children are generally less affected by COVID-19 than adults, they can become infected with the virus, and some will develop serious illness.

Children at increased risk of severe COVID-19 include those with complex medical problems; neurological, genetic, or metabolic conditions; congenital heart disease; or any of the conditions listed above, such as diabetes or obesity.

Coronavirus Transmission: How Does COVID-19 Spread?

How Contagious Is COVID-19?

The virus that causes COVID-19 can spread more efficiently than the seasonal flu, says the CDC.

In general, the closer and more prolonged an interaction with an infected person, the greater the likelihood of COVID-19 transmission, according to the CDC.

The delta variant, which is currently the dominant variant, is more than twice as contagious as earlier forms of the coronavirus and causes more infections. Even so, COVID-19 vaccines continue to provide powerful protection against hospitalization and death.

Person-to-Person Transmission

COVID-19 is primarily spread through respiratory droplets and aerosols produced when an infected person coughs, sneezes, or talks. Transmission can occur when these virus-laden droplets or aerosols land in someone else’s eyes, nose, or mouth or are inhaled, according to the CDC.

The aerosols that are produced by a person with COVID-19 can remain suspended in the air, travel distances beyond six feet, and be breathed in by others, scientists have found.

People can spread the virus without having symptoms. According to studies cited by the CDC in a brief on the effectiveness of mask wearing, it’s estimated that asymptomatic or presymptomatic cases are responsible for more than 50 percent of transmissions of the virus.

While vaccines are helping guard against so-called superspreading events, in which one person infects a large number of others, individuals living in areas where immunization rates are low continue to be at risk, particularly in light of the ultracontagious delta variant. In July 2021, more than 125 campers and adults who attended a summer camp run by a South Texas church camp tested positive for COVID-19, CNN and other news media reported.

What Is Community Spread?

In the event that someone tests positive for COVID-19, health officials try to determine how the person contracted the disease.

If the source of the illness is unknown, this is called community spread. The CDC first confirmed a possible instance of community spread in the United States on February 26, 2020.

What Is Herd Immunity?

Herd immunity, also known as population immunity, means that people in a community are largely protected from getting an infectious disease such as COVID-19 because enough of them have already had it or because they’ve received a vaccine.

Achieving herd immunity is important because it means COVID-19 cannot spread readily, so even those who can’t be vaccinated, such as newborns, are protected. When SARS-CoV-2 first appeared, essentially no one was immune; the virus could spread quickly from person to person.

According to many experts, achieving herd immunity against COVID-19 might require as much as 85 percent of the population to be vaccinated or develop natural immunity by becoming infected with the coronavirus.

In an interview with CNBC News in September, Anthony Fauci, MD, the government’s top infectious disease expert, gave estimates of “75, 80, 85 percent” and “75 to 80-plus percent.”

What Is the Incubation Period for COVID-19?

The incubation period is the time from when a person was exposed to the virus until the first symptoms develop. The median incubation period for COVID-19 is four to five days from exposure; close to 98 percent of all people who develop symptoms do so within 11.5 days of the infection.

New Coronavirus Variants

All viruses, including the virus that causes COVID-19, constantly change by mutating, creating new variants. These new variants can emerge and disappear or emerge and begin to spread.

New variants of SARS-CoV-2, the virus that causes COVID-19, present a global threat. The current “variant of concern” is delta, which was first identified in India and which spreads much faster than other variants and may cause more severe cases.

While the three COVID-19 vaccines available in the United States provide strong protection against serious illness and death caused by delta, so-called breakthrough infections do occur.

One reason to immunize as many people as possible is to prevent new variants from emerging that might be more dangerous and better able to elude the current vaccines.

How Long Does COVID-19 Last on Surfaces?

It’s possible to get COVID-19 by touching a surface contaminated with the virus, then touching your mouth, nose, or eyes, but this isn’t the main way the coronavirus spreads, according to the CDC. In fact, the CDC says your odds of catching COVID-19 from a contaminated surface are less than 1 in 10,000.

To reduce the risk of contracting COVID-19 from a surface, the CDC recommends that people practice frequent hand-washing with soap and water for at least 20 seconds. If soap and water aren’t available, hand sanitizer that contains at least 60 percent alcohol is the next best way to get rid of germs.

And when it comes to cleaning at home, the CDC says that disinfecting to reduce the spread of COVID-19 is likely unnecessary unless someone living in your home has COVID-19, or someone who tested positive for COVID-19 was in your home within the past 24 hours.

Can COVID-19 Be Spread Through Food and Groceries?

Although surfaces may pose a COVID-19 risk, the CDC released a statement in May that the primary and most important way that the virus spreads is through close person-to-person contact.

According to the shopping-for-food guidelines issued by the U.S. Food and Drug Administration (FDA), there is no evidence of food packaging being associated with the transmission of COVID-19.

Testing for COVID-19: What Are the Types of COVID-19 Tests?

The three types of tests for the novel coronavirus are molecular tests (also called PCR tests), antigen tests, and antibody tests.

Molecular Tests

These tests are diagnostic or viral tests that are used to determine if someone is currently infected with COVID-19. A molecular test, such as a reverse transcription polymerase chain reaction (RT-PCR) test, detects the virus’s genetic material. Specimens can be collected with a nasal or throat swab or through a saliva sample.

Antigen Tests

Antigen tests look for specific proteins from the virus. Although not as accurate at RT-PCR tests, they don’t require as much equipment and the results can usually be delivered faster.

Both molecular and antigen tests for COVID-19 are available as at-home collection kits (usually with a doctor’s prescription) where a sample is collected at home and mailed to a lab for results.

The FDA has also given the nod to several over-the-counter, at-home coronavirus testing kits that provide results in approximately 15 to 30 minutes.

Antibody Tests

These tests use a finger prick or blood draw to look for antibodies — evidence that a person’s body has formed an immune response to the infection, which would indicate that a person had the virus and recovered. Antibody tests (also called serology tests) can be used to better determine the total number of cases of COVID-19 in a particular area.

This test only shows if you’ve had the virus in the past — if you have the test when you first develop COVID-19, it might not detect antibodies, according to the FDA.

How Reliable Are the Tests for COVID-19?

There are hundreds of authorized diagnostic tests for COVID-19, all with different levels of accuracy. Additional factors can influence whether the results are correct, including the following:

The quality of the specimen taken
How the specimen was stored before testing
If the person taking the test has symptoms
How much virus the person sheds
People who are early or late in the course of their illness with COVID-19

In general, molecular tests using a nasal swab are the gold standard because they are the most accurate.

Repeat testing with antigen kits can help compensate for their lower sensitivity; plus they are valuable when getting a speedy result is vital.

Duration of COVID-19

When it comes to how long a person might feel sick with COVID-19, there is a broad spectrum. “Some people never feel sick or have symptoms — that’s one extreme,” says David Lee Thomas, MD, MPH, the director of the division of infectious diseases and a professor of medicine at Johns Hopkins Medicine in Baltimore. “On the other side, you have individuals who were infected with the virus over three months ago and have not stopped feeling sick.”

People with a mild case of COVID-19 usually recover within one to two weeks, according to Johns Hopkins Medicine. For those with a severe case, the illness may last six weeks or longer, and could lead to lasting damage to the heart, kidney, lungs, and brain.

COVID-19 Long-Haulers

Some people who become ill with COVID-19 continue to experience symptoms for weeks and even months after they are diagnosed, perplexing their doctors. Research published in JAMA Network Open in February 2021 found that as many as 1 in 3 COVID-19 outpatients in the study developed persistent symptoms after the initial infection, including extreme fatigue, loss of sense of smell or taste, and “brain fog.”

There are at least two Facebook support groups and a Slack channel called Body Politic on which people with “long COVID” share their experiences and talk about techniques that have helped them cope.

Vaccines and Treatments for COVID-19

Here’s a rundown of the different ways to fight COVID-19.

COVID-19 Vaccine Update

In December 2020, the FDA issued emergency use authorizations (EUAs) for the Pfizer-BioNTech and Moderna vaccines. The Pfizer vaccine received full FDA approval in August 2021.

Both companies completed large trials in which researchers gave the vaccine to tens of thousands of subjects and monitored how many people became infected with the virus compared with volunteers who received a placebo.

The Pfizer-BioNTech vaccine was found to be 95 percent effective in preventing symptomatic COVID-19 among clinical trial participants.

The vaccine developed by Moderna was found to be 94.5 percent effective.

The Pfizer and Moderna vaccines both use a genetic molecule called messenger RNA (mRNA). The mRNA gives instructions to human cells to create a harmless piece of what is called a spike protein, similar to a protein on the surface of the coronavirus, according to the CDC. This triggers the immune system to create antibodies against the coronavirus.

The Pfizer vaccine is approved for people ages 5 and older, and the Moderna vaccine is authorized for those 18 and older.

The FDA issued an EUA for a third vaccine, by the Johnson & Johnson (J&J) subsidiary Janssen, in February 2021.

The J&J vaccine involves a single jab, unlike the Pfizer and Moderna vaccines, which are administered in two doses spaced several weeks apart. The J&J vaccine was found to be 85 percent effective in preventing severe COVID-19 in international trials; in U.S. trials, it proved to be 72 percent effective at preventing mild to severe COVID-19.

While the Pfizer and Moderna vaccines use mRNA, the J&J vaccine employs a genetically modified adenovirus — the type of virus that causes many common colds — to instruct cells to produce a piece of the spike protein.

While the vaccines are somewhat less effective overall against the delta variant, they continue to provide strong protection against hospitalization and death.

So-called “adverse effects” of COVID-19 vaccination are rare, and in the United States include:

Anaphylaxis (severe allergic reaction), occurring in approximately 2 to 5 people per million
Thrombosis with thrombocytopenia syndrome (blood clots with low platelets) after J&J vaccination, with 47 confirmed reports out of 15.3 million doses administered as of October 20, 2021
Guillain-Barré syndrome after J&J vaccination, with 238 preliminary reports out of 15.3 million doses
Myocarditis and pericarditis (heart inflammation issues), with 963 confirmed reports out of 15.3 million doses

COVID-19 Booster Shots

In September and October 2021 the U.S. government issued a set of recommendations for COVID-19 booster shots, to counter the waning effectiveness of the vaccines over time and the threat of the delta variant.

For individuals immunized with the Pfizer or Moderna vaccine, the FDA and CDC recommend boosters for those who are 65 and older; those 18 and older with underlying health conditions that increase their risk of severe COVID-19; and those 18 and older who are at higher risk of exposure to COVID-19 because of their jobs or living situation.

These people should get their booster no sooner than six months after completing their initial vaccination.

Acknowledging that the one-shot Johnson & Johnson vaccine is less effective than the two-dose Pfizer or Moderna, the federal agencies recommend boosters for everyone age 18 and older who received a J&J vaccine more than two months prior.

COVID-19 Vaccines and Boosters for People Who Are Moderately to Severely Immunocompromised

Individuals who are moderately to severely immunocompromised are at particular risk from COVID-19 because they may not be able to develop strong immunity in response to vaccination. Based on CDC guidelines, those 18 and over are eligible for a third shot of either a Pfizer of Moderna vaccine at least 28 days after completing their initial two-dose regimen and may opt to get a fourth shot at least six months later.

The CDC recommends that individuals in this moderately to severely immunocompromised group who initially received a Johnson & Johnson vaccine get a second shot at least two months after receiving their primary dose.

People in this highly vulnerable group, age 18 and up, include those who have:

Been receiving active cancer treatment for tumors or cancers of the blood
Received an organ transplant and are taking medicine to suppress the immune system
Moderate to severe primary immunodeficiency (such as DiGeorge syndrome)
Advanced or untreated HIV infection
Active treatment with high-dose corticosteroids or other drugs that may suppress the immune response

Medications for COVID-19

Medications for COVID-19 work in one of three ways: They keep the virus from entering cells, prevent the virus from replicating in cells, or minimize the damage the virus inflicts on the organs.

“There are quite a variety of compounds currently under investigation,” says Rama Mallampalli, MD, the chair of the department of internal medicine at the Ohio State University College of Medicine in Columbus. “Many anti-inflammatory and antiviral medications that have been approved by the FDA in the past for other illnesses are being redeployed for COVID-19.”

Currently there is one FDA-approved medication for COVID-19 and several drugs, biological products, and combination therapies that are authorized by the FDA for emergency use, with varying levels of effectiveness and safety. These include:

Remdesivir This antiviral medication became the first FDA-approved treatment for COVID-19 in October 2020. It is used to treat adults and children over the age of 12 who are hospitalized due to COVID-19.
Monoclonal Antibodies These laboratory-produced molecules act as supplemental antibodies.
COVID-19 Convalescent Plasma Antibody-rich plasma from people who have recovered from COVID-19 can help currently infected people mount an immune response.
Baricitinib (Olumiant) in Combination With Remdesivir Olumiant is an immune modulator used in rheumatoid arthritis.

Remdesivir and Other Antivirals

Antivirals kill or prevent the growth of viruses by targeting a specific part of the life cycle that is necessary for them to reproduce, according to Harvard Medical School.

Drugs that were designed to treat other viral infections (such as different types of hepatitis or HIV) are being studied to see if they can help fight the coronavirus. As of October 2021, close to 600 studies are underway to evaluate antivirals’ efficacy against the infection that causes COVID-19.

One key trial, published in The New England Journal of Medicine on November 5, 2020, found that the antiviral remdesivir was superior to placebo in shortening recovery time for adults hospitalized with COVID-19 who had lower respiratory tract infection.

Expectations are high for an antiviral pill called molnupiravir, which drug companies Merck and Ridgeback say can cut the risk of hospitalization or death from COVID-19 in half for adults with mild or moderate disease who are at high risk for developing severe illness.

The FDA will meet on November 30 to discuss emergency use authorization.

Meanwhile, Pfizer has been developing its own protease-inhibitor antiviral called Paxlovid. In clinical trials results released on November 5, 2021, the new drug reduced hospitalizations by 89 percent compared to placebo and completely prevented death. Unlike Merck's molnupiravir, however, Paxlovid must be given with a booster drug called ritonavir to prevent the body from breaking down the antiviral too quickly.

Corticosteroids

Steroids, which are commonly prescribed for allergies or asthma, have been successfully used in treating hospitalized people with COVID-19, says Dr. Mallampalli. “Steroids have been shown to help people who were on oxygen to not get worse and have to go on respirators, and they helped prevent death in people who were already on respirators,” he says.

The synthetic steroid dexamethasone reduced the death of COVID-19 patients on ventilators by one-third in the University of Oxford’s RECOVERY study, according to a report by the investigators published in February 2021 in The New England Journal of Medicine.

Monoclonal Antibodies

Monoclonal antibodies are laboratory-made molecules designed to serve as substitute antibodies that can restore, enhance, or imitate the immune system’s attack against certain diseases, including COVID-19. These treatments work by helping the body’s natural immune defense against COVID-19.

Several monoclonal antibody treatments are authorized for people with mild or moderate COVID-19 who are at high risk for developing severe disease. These treatments include the combination of bamlanivimab and etesevimab;

the combination of casirivimab and imdevimab (REGEN-COV2); and the monoclonal antibody sotrovimab (Xevudy).

Convalescent Plasma

“The use of convalescent plasma is not a new idea — it’s been around for about 100 years. It’s been used for other coronaviruses, such as severe acute respiratory syndrome (SARS) and Middle East respiratory virus (MERS),” says Mallampalli.

This method works by taking plasma from people who have recovered from infection and giving it to people who are critically ill, explains Mallampalli. “At first, this therapy was reserved for the most severely ill patients, but now inventory of the plasma is higher,” he says.

The FDA issued an emergency use authorization for convalescent plasma in August 2020 based on evidence that it “may be effective in lessening the severity or shortening the length of COVID-19 illness in some hospitalized patients,” according to an FDA statement.

Immune Modulators and Cytokine Storms

In an acute reaction to the COVID-19 infection, the body produces different substances, including compounds called cytokines. Although cytokines play an important role in normal immune responses, some people make them in very large amounts, a phenomenon called a cytokine storm. This extreme immune response can be a life-threatening complication of COVID-19.

Scientists are testing certain immune modulators to find out if they decrease the production of inflammation without interfering with other important immune functions, according to a study published in May 2020 in Lancet Rheumatology.

So far one of these medications has been granted EUA use for COVID-19, baricitinib. It blocks the activity of one or more of a specific family of enzymes, thus interfering with the pathway that leads to inflammation. The drug is sold under the name Olumiant and is FDA-approved for the treatment of rheumatoid arthritis. It is approved for use in COVID-19 only when combined with remdesivir.

The combination of the two drugs was shown to reduce recovery time within 29 days compared with remdesivir alone.

Immunomodulators are still actively being evaluated for their benefit in the treatment of COVID-19.

Can Supplements Boost Immunity Against COVID-19?

At this time, there isn’t any conclusive evidence that a dietary supplement or additive can combat COVID-19, says Mallampalli.

Studies suggest that some vitamins and supplements can help reduce the likelihood of catching a respiratory virus (not the novel coronavirus specifically) or reduce the amount of time a person is ill, according to Tod Cooperman, MD, the president and founder of ConsumerLab.com, a provider of independent test results and information designed to help consumers and healthcare professionals identify the best-quality health and nutrition products.

Some supplements can be dangerous if taken in high doses or can interact with some medications, so it’s important to talk with your doctor before taking any supplements, says Dr. Cooperman.

Vitamin C is associated with shortening the duration of colds in some adults, and in some groups of people, it even seems to reduce the risk of catching a cold, according to a report published in 2013 in the Cochrane Database of Systematic Reviews.

The common cold is sometimes caused by a type of coronavirus.

Zinc has a role in immune function, and it may have some benefit in preventing or making COVID-19 less severe, but there is no proof of this yet. In other viruses, zinc has been shown to inhibit virus activity in the throat and can help lessen symptoms, says Cooperman.

The National Institutes of Health COVID-19 Treatment Guidelines Panel recommends against using zinc supplementation above the recommended dietary allowance for the prevention of COVID-19 unless a person is in a clinical trial.

Magnesium is vital for a strong immune system. A small study published in the November–December 2020 Nutrition found that a combination of vitamin D, magnesium, and vitamin B12 was associated with a significant reduction of clinical deterioration in people with COVID-19.

Vitamin D has been shown to be important in offering some protection against infections. “I’m an advocate of people taking vitamin D, especially if they are vitamin D deficient,” Mallampalli says, adding, “It’s not clear from the available evidence whether or not a deficiency predisposes someone to COVID-19.”

Taking a vitamin D supplement regularly was significantly associated with a 34 percent lower risk of COVID-19 infection, according to a study published in January 2021 in the American Journal of Clinical Nutrition.

Have a discussion with your physician before taking any kind of supplement, especially if you are planning to use it long-term or at high doses, in order to understand the risks, benefits, and latest research as they pertain to your individual situation. If you need more help, seek out a board-certified physician trained in integrative medicine.

COVID-19 Prevention: How to Stop the Spread

While vaccination is a key way to prevent the spread of COVID-19, other practices continue to be vital.

Social Distancing

The standard definition of social distancing for COVID-19 in the United States has been for people to keep at least six feet away from others who are not in their household.

The goal is to prevent exposure to infected respiratory droplets and aerosols emitted by another person when coughing, sneezing, or talking.

Self-Isolation

People with COVID-19 may be advised to self-isolate so they don’t spread the virus to other people. Self-isolation means staying away even from members of one’s own household who don’t have the virus. Mayo Clinic advises the following practices:

Don’t share dishes, glasses, bedding, or other household items.
Sleep in a separate bedroom (if possible).
Use a separate bathroom (if possible).
Call your doctor if your symptoms get worse.

CDC guidelines suggest self-isolating for 10 days after symptoms first appeared and you have been fever-free for 24 hours and your other symptoms are improving. If you never had symptoms but tested positive, you should self-isolate for 10 days after taking the test.

Contact Tracing

Contact tracing is one way to slow the spread of COVID-19. In contact tracing, people who test positive for the virus are asked to identify individuals they may have had close contact with while they were infected.

Contact tracers then notify those people, without identifying who may have exposed them, and offer referrals for COVID-19 testing. Potentially infected individuals who are not vaccinated will be asked to stay home and social distance from others until 14 days after the possible exposure, according to CDC guidelines.

Wearing Masks

Data about the effectiveness of wearing a mask largely come from observational and epidemiological studies (that compare the spread of the virus in communities or populations who wear masks versus those who don’t). Research shows that masks reduce the spread of the virus by about 70 percent.

The CDC recommends that people ages 2 and up who are not vaccinated wear a mask in any indoor public setting, while those who are vaccinated are advised to wear a mask in crowded indoor settings in areas where there is high COVID-19 transmission; this will provide extra protection against the delta variant.

In general, wearing a mask outside is not considered necessary even if you are unvaccinated, unless you are in a crowded space in an area with a lot of COVID-19 transmission.

People who are moderately or severely immunocompromised are extra vulnerable to delta, even if they’re vaccinated, so are advised to follow the same masking recommendations as unvaccinated people.

Properly Washing Your Hands

Hand-washing is another important part of the effort to stop the transmission of COVID-19, according to the CDC. The agency recommends the following steps:

Wet your hands with clean running water, turn off tap, and apply soap.
Lather your hands by rubbing them together. Make sure you lather the backs of your hands, between your fingers, and under your fingernails.
Continue to scrub your hands for at least 20 seconds. If you need help with timing, sing or hum “Happy Birthday” from beginning to end twice.
Turn on the tap and rinse your hands with clean running water.
Dry your hands with a clean towel or air-dry them.

Complications of COVID-19

COVID-19 can cause serious medical complications and even death. Although anyone can develop complications as a result of the virus, the risk is greater in older adults and people with existing chronic medical conditions. Mayo Clinic lists the following as among the most common serious complications that arise with the disease:

Pneumonia and trouble breathing
Organ failure in several organs
Heart problems
Acute respiratory distress syndrome, a severe lung condition that causes a low amount of oxygen to go through your bloodstream to your organs
Blood clots
Acute kidney injury
Additional viral and bacterial infections

Research and Statistics: How Many People Have COVID-19?

Mortality Rate

According to the Johns Hopkins coronavirus dashboard, as of October 28, 2021, there were more than 45 million confirmed cases of the virus in the United States and the mortality rate was 1.6 percent.

That means the available data showed that 16 people die out of every 1,000 who are confirmed to have the virus.

COVID-19 Cases by Race

Although racial and ethnic information for people with COVID-19 in the United States is incomplete, it is clear that Black Americans and other historically disadvantaged groups are getting COVID-19 and dying from it at a disproportionately high rate compared with the total population, according to Lisa A. Cooper, MD, writing on the Johns Hopkins University Coronavirus Resource Center.

An October 2021 report from the Kaiser Family Foundation found that, after adjusting for age differences, Hispanic, Black, and American Indian and Alaska Native (AIAN) people are at least twice as likely to die from COVID-19 as their white counterparts, and Hispanic and AIAN people are at nearly 2 times greater risk of COVID-19 infection compared with white people.

Can Children Get COVID-19?

Fewer children and teens have become infected with COVID-19 compared with adults, and they usually don’t get as sick as adults with the virus, notes the CDC.

Most children with COVID-19 have mild symptoms or have no symptoms.

Evidence suggests that children who get COVID-19 produce weaker antibodies and fewer types of them compared with adults. Researchers believe that’s because children clear the infection much faster than adults; this could also explain why they typically don’t experience severe symptoms, according to an article published in November 2020 in Nature.

If children do develop symptoms, these are usually mild and nonspecific, such as headache or sore throat, according to the CDC.

Children who have underlying medical issues might be at increased risk for severe COVID-19.

Multisystem inflammatory syndrome in children (MIS-C) can be a complication of COVID-19, though it is very rare. According to the CDC, children with MIS-C may experience ongoing fever plus one or more of the following:

Stomach pain
Bloodshot eyes
Diarrhea
Dizziness or lightheadedness
Skin rash
Vomiting

COVID-19 and Your Mental Health

The pandemic has led to an increase in stress and mental health issues. Fear of the virus, the loss of loved ones, unemployment, and social isolation are just a few of the factors that have made life difficult.

A study published in September 2020 in JAMA Network Open found that 27.8 percent of adults had symptoms of depression as of mid-April compared with 8.5 percent of people pre-pandemic.

Investigators found that income and savings were the factors most associated with depression symptoms during the pandemic.

The pandemic has increased suicide risk as well as the risk of developing an addiction. If you or someone you love has thoughts of self-harm or is struggling with addiction, reach out to a physician or mental health provider, or call the National Suicide Prevention Lifeline at 1-800-273-8255 (TALK) or the Substance Abuse and Mental Health Services Administration (SAMHSA) at 1-800-662-4357 (HELP) for free, confidential help.

Self-Care During the COVID-19 Pandemic

It’s important to acknowledge how challenging the pandemic is for you and the people around you. Make sure that you take time for yourself: It can help you stay healthy both mentally and physically.

Try to get up and go to bed at about the same time every day, and make sure you’re getting enough sleep. For most adults, that’s seven to nine hours, according to the National Sleep Foundation.

It’s important to find ways to get enough physical activity, notes the CDC.

Even if it’s just a walk around the block or a dance party in your living room, try to get 150 minutes of moderate exercise or 75 minutes of vigorous exercise every week, the amount recommended by the CDC’s National Center for Chronic Disease Prevention and Health Promotion.

The CDC suggests trying to maintain a healthy diet; avoid eating too much processed junk foods and refined sugar, and limit the amount of caffeine and alcohol you consume.

Try to reduce the amount of time you spend looking at your phone, computer, or television. Stay informed about the virus and the recommended precautions, but take daily "news vacations" and allow yourself to unplug for a few hours each day, suggests the CDC.

Keep a positive mindset and focus on the good things in your life to boost your mental and physical state. One way to start is by keeping a gratitude journal.

Additional reporting by Pamela Kaufman.

Editorial Sources and Fact-Checking

How Much Physical Activity Do Adults Need? Centers for Disease Control and Prevention. October 7, 2020.
Coping With Stress. Centers for Disease Control and Prevention. July 22, 2021.
How Much Sleep Do We Really Need? National Sleep Foundation. March 10, 2021.
For Parents: Multisystem Inflammatory Syndrome in Children (MIS-C) associated with COVID-19. Centers for Disease Control and Prevention. September 20, 2021.
Families & Children. Centers for Disease Control and Prevention. August 2, 2021.
Racial Data Transparency. Johns Hopkins Coronavirus Resource Center.
Mortality Analyses. Johns Hopkins Coronavirus Resource Center.
Coronavirus Disease 2019 (COVID-19). Mayo Clinic. December 17, 2021.
Contact Tracing. Centers for Disease Control and Prevention. October 19, 2021.
What’s the difference between quarantine and isolation? Mayo Clinic. March 20, 2020.
Scientific Brief: SARS-CoV-2 Transmission. Centers for Disease Control and Prevention. May 7, 2021.
Habitual Use of Vitamin D Supplements and Risk of Coronavirus Disease 2019 (COVID-19) Infection: A Prospective Study in UK Biobank. American Journal of Clinical Nutrition. January 29, 2021.
Zinc. National Institutes of Health. April 21, 2021.
Immunomodulators Under Evaluation for the Treatment of COVID-19. National Institutes of Health. December 16, 2021.
Coronavirus (Covid-19) Update: FDA Authorizes Drug Combination for Treatment of Covid-19. U.S. Food and Drug Administration. November 19, 2020.
FDA Issues Emergency Use Authorization for Convalescent Plasma as Potential Promising COVID-19 Treatment, Another Achievement in Administration’s Fight Against Pandemic. U.S. Food and Drug Administration. August 23, 2020.
Coronavirus (COVID-19) Update: FDA Authorizes Monoclonal Antibody for Treatment of COVID-19. U.S. Food and Drug Administration. November 21, 2020.
Coronavirus (COVID-19) Update: FDA Authorizes Monoclonal Antibodies for Treatment of COVID-19. U.S. Food and Drug Administration. February 9, 2021.
Emergency Use Authorization. U.S. Food and Drug Administration. December 17, 2021.
Johnson & Johnson Announces Submission of Application to the U.S. FDA for Emergency Use Authorization of Its Investigational Single-Shot Janssen COVID-19 Vaccine Candidate. Johnson & Johnson. February 4, 2021.
Understanding mRNA COVID-19 Vaccines. Centers for Disease Control and Prevention. November 3, 2021.
FDA Takes Additional Action in Fight Against COVID-19 by Issuing Emergency Use Authorization for Second COVID-19 Vaccine. U.S. Food and Drug Administration. December 18, 2020.
FDA Takes Key Action in Fight Against COVID-19 by Issuing Emergency Use Authorization for First COVID-19 Vaccine. U.S. Food and Drug Administration. December 11, 2020.
Different COVID-19 Vaccines. Centers for Disease Control and Prevention. December 14, 2021.
Shmerling RH. Which Test Is Best for COVID-19? Harvard Health Blog. January 5, 2021.
A Closer Look at COVID-19 Diagnostic Testing. U.S. Food and Drug Administration. March 18, 2021.
Coronavirus (COVID-19) Update: FDA Authorizes First Covid-19 Test for Self-Testing at Home. U.S. Food and Drug Administration. November 17, 2020.
Coronavirus Disease 2019 Testing Basics. U.S. Food and Drug Administration. September 22, 2021.
Shopping for Food During the COVID-19 Pandemic — Information for Consumers. U.S. Food and Drug Administration. May 1, 2020.
CDC Updates COVID-19 Transmission Webpage to Clarify Information About Types of Spread. Centers for Disease Control and Prevention. May 23, 2020.
When and How to Wash Your Hands. Centers for Disease Control and Prevention. August 10, 2021.
Interim Clinical Guidance for Management of Patients With Confirmed Coronavirus Disease (COVID-19). Centers for Disease Control and Prevention. February 16, 2021.
Science Brief: Community Use of Masks to Control the Spread of SARS-CoV-2. Centers for Disease Control and Prevention. December 6, 2021.
How COVID-19 Spreads. Centers for Disease Control and Prevention. July 14, 2021.
People With Certain Medical Conditions. Centers for Disease Control and Prevention. December 14, 2021.
Maragakis L. Who Is at High Risk for Severe Coronavirus Disease? Johns Hopkins Medicine. December 8, 2021.
Maragakis L. Coronavirus Diagnosis: What Should I Expect? Johns Hopkins Medicine. October 22, 2020.
Frequently Asked Questions. Centers for Disease Control and Prevention. October 21, 2021.
Symptoms of Coronavirus. Centers for Disease Control and Prevention. February 22, 2021.
Makaronidis J, Mok J, Balogun N, et al. Seroprevalence of SARS-CoV-2 Antibodies in People With an Acute Loss in Their Sense of Smell and/or Taste in a Community-Based Population in London, UK: An Observational Cohort Study. PLoS Medicine. October 1, 2020.
Lechien JR, Chiesa-Estomba CM ,Beckers E, et al. Prevalence and 6-Month Recovery of Olfactory Dysfunction: A Multicenter Study of 1,363 COVID-19 Patients. Journal of Internal Medicine. January 5, 2021.
Baeck Marie, Herman A. COVID Toes: Where Do We Stand With the Current Evidence? International Journal of Infectious Diseases. January 2021.
Colmenero I, Santonja C, Alonso-Riaño M, et al. SARS‐CoV‐2 Endothelial Infection Causes COVID‐19 Chilblains: Histopathological, Immunohistochemical, and Ultrastructural Study of Seven Pediatric Cases. British Journal of Dermatology. June 20, 2020.
Hemilä H, Chalker E. Vitamin C for Preventing and Treating the Common Cold. Cochrane Database of Systematic Reviews. January 31, 2013.
Tan CW, Ho LP, Kalimuddin S, et al. Cohort Study to Evaluate the Effect of Combination Vitamin D, Magnesium, and Vitamin B12 (DMB) on Progression to Severe Outcome in Older Patients with Coronavirus. Nutrition. November 2020.
Ma H, et al. Habitual Use of Vitamin D Supplements and Risk of Coronavirus Disease 2019 (COVID-19) Infection: A Prospective Study in UK Biobank. American Journal of Nutrition. January 29, 2021.
Beigel JH, Tomashek KM, Dodd LE, et al. Remdesivir for the Treatment of COVID-19 — Preliminary Report. The New England Journal of Medicine. November 5, 2020.
The RECOVERY Collaborative Group. Dexamethasone in Hospitalized Patients With COVID-19. The New England Journal of Medicine. July 17, 2020.
Zhong J, Tang J, Ye C, et al. The Immunology of COVID-19: Is Immune Modulation an Option for Treatment? Lancet Rheumatology. July 1, 2020.
Weisberg SP. Distinct Antibody Responses to SARS-CoV-2 in Children and Adults Across the COVID-19 Clinical Spectrum. Nature Immunology. November 5, 2020.
Ettman CK, et al. Prevalence of Depression Symptoms in US Adults Before and During the COVID-19 Pandemic. JAMA Network Open. September 2, 2020.
Science Brief: SARS-CoV-2 and Surface (Fomite) Transmission for Indoor Community Environments. Centers for Disease Control and Prevention. April 5, 2021.
Cleaning and Disinfecting Your Home. Centers for Disease Control and Prevention. June 17, 2021.
Cleaning and Disinfecting Your Facility. Centers for Disease Control and Prevention. November 15, 2021.
Alzheimer's Disease and Healthy Aging: COVID-19 Risks and Vaccine Information for Older Adults. Centers for Disease Control and Prevention. August 2, 2021.
Delta Variant: What We Know About the Science. Centers for Disease Control and Prevention. August 26, 2021.
CNBC Transcript: Dr. Anthony Fauci Speaks with CNBC’s Meg Tirrell Live During the CNBC Healthy Returns Livestream Today. CNBC. December 16, 2021.
Logue JK et al. Sequelae in Adults at 6 Months After COVID-19 Infection. JAMA Open Network. February 19, 2021.
8 Things to Know About Johnson & Johnson's Janssen COVID-19 Vaccine. Johnson & Johnson. February 27, 2021.
Selected Adverse Events Reported after COVID-19 Vaccination. Centers for Disease Control and Prevention. December 16, 2021.
CDC Expands Eligibility for COVID-19 Booster Shots. Centers for Disease Control and Prevention. October 21, 2021.
Interim Clinical Considerations for Use of COVID-19 Vaccines Currently Approved or Authorized in the United States. Centers for Disease Control and Prevention. December 17, 2021.
COVID-19 Vaccines for Moderately or Severely Immunocompromised People. Centers for Disease Control and Prevention. December 14, 2021.
ClinicalTrials.gov. U.S. Library of Medicine.
FDA to Hold Advisory Committee Meeting to Discuss Merck and Ridgeback’s EUA Application for COVID-19 Oral Treatment. U.S. Food and Drug Administration. October 14, 2021.
Pfizer’s Novel COVID-19 Oral Antiviral Treatment Candidate Reduced Risk of Hospitalization or Death by 89% in Interim Analysis of Phase 2/3 EPIC-HR Study. Pfizer. November 5, 2021.
Quarantine and Isolation. Centers for Disease Control and Prevention. December 9, 2021.
Your Guide to Masks. Centers for Disease Control and Prevention. October 21, 2021.
COVID-19 Cases and Deaths by Race/Ethnicity: Current Data and Changes Over Time. Kaiser Family Foundation. October 8, 2021.
Science Brief: Transmission of SARS-CoV-2 in K-12 Schools and Early Care and Education Programs – Updated. Centers for Disease Control and Prevention. December 17, 2021.
Allen K. More than 125 Covid-19 cases tied to South Texas church camp, pastor says. CNN. July 6, 2021.

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