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
- Shortness of breath or difficulty breathing
- Muscle or body aches
- New loss of taste or smell
- Sore throat
- Congestion or runny nose
- Nausea or vomiting
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.
How Much Do You Know About the Coronavirus?
Causes and Risk Factors of COVID-19
Older Adults Are at Higher Risk for COVID-19
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
- 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
- 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
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?
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.
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.
What Is the Incubation Period for COVID-19?
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?
Can COVID-19 Be Spread Through Food and Groceries?
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.
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.
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.
How Reliable Are the Tests for COVID-19?
- 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.
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.”
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.
How Was the COVID-19 Vaccine Developed So Quickly?
The Pfizer vaccine is approved for people ages 5 and older, and the Moderna vaccine is authorized for those 18 and older.
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 vaccines are somewhat less effective overall against the delta variant, they continue to provide strong protection against hospitalization and death.
- 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.
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.
- 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.”
- 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
The FDA will meet on November 30 to discuss emergency use authorization.
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.
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.
“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.
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.
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.
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.
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.
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.”
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.
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.
- 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.
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.
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.
Properly Washing Your Hands
- 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
- 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?
COVID-19 Cases by Race
Can Children Get COVID-19?
Children who have underlying medical issues might be at increased risk for severe COVID-19.
- Stomach pain
- Bloodshot eyes
- Dizziness or lightheadedness
- Skin rash
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.
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.
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.
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.
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