What Is a Coronavirus?

Chinese health officials first reported cases of acute respiratory illness associated with a seafood and animal market in the city of Wuhan on December 31, 2019. A week later, they confirmed that a novel coronavirus, SARS-CoV-2, was associated with this initial cluster of cases, according to the Centers for Disease Control and Prevention (CDC). (1) The first confirmed case of COVID-19, the disease caused by SARS-CoV-2, in the United States was reported on January 21, 2020; by the end of March, the number of cases had climbed to 188,200, according to the Johns Hopkins University Coronavirus Resource Center. (2)

A “novel” coronavirus (CoV) means it’s a new strain of coronavirus that hasn’t been seen or identified before.

Coronaviruses can range from a common cold to more serious illnesses, like severe acute respiratory syndrome (SARS). Symptoms can be mild, with just a runny nose or cough, but can also become much more serious, including fever and even pneumonia. In some cases, a coronavirus can be fatal, especially in frailer people or those with preexisting medical conditions, such as heart disease or diabetes, notes the World Health Organization (WHO). (3)

Human coronaviruses were first identified in the mid-1960s, and there are currently seven that can infect people. They include 229E (alpha coronavirus), NL63 (alpha coronavirus), OC43 (beta coronavirus), HKU1 (beta coronavirus), MERS-CoV, SARS-CoV, and SARS-CoV-2, the latest coronavirus to be transmitted to humans.

It is very common for people around the world to be infected with 229E, NL63, OC43, and HKU1. These viruses usually cause a mild to moderate upper respiratory tract illness — basically, a common cold, according to the CDC. (4)

These coronaviruses can also cause lower respiratory tract illnesses, such as pneumonia and bronchitis. People with cardiopulmonary disease or weaker immune systems, as well as infants and elderly people, are at higher risk, notes the CDC. (5)

SARS is a viral respiratory illness that was first reported in Asia in February of 2003. It spread to 29 countries and infected 8,096 people, 774 of whom died.

Although SARS did come to the United States, only eight people contracted the illness and no one died as a result. There is now no known SARS transmission anywhere in the world, the most recent case having been reported in China in April 2004, according to the CDC. (6)

Typically, SARS starts with a fever higher than 100.4 degrees F. Other symptoms of the virus can include headache, overall discomfort, and body aches. Some people have mild respiratory symptoms and diarrhea. Most people with SARS develop pneumonia.

It’s suspected that SARS started in bats and potentially spread to civet cats before spilling over to infect humans, notes the WHO. (7) Although SARS came from an animal host, it was mainly transmitted human to human through close contact. It spreads as many coronaviruses do, via tiny respiratory droplets that land in the mouth, nose, or eyes of a nearby person when an infected person coughs or sneezes, per the CDC. (8)

This viral respiratory disease was first identified in Saudi Arabia in 2012, and approximately 80 percent of human cases have been in that country. The virus can cause fever, cough, shortness of breath, and sometimes gastrointestinal symptoms, including diarrhea. People with MERS often develop pneumonia.

MERS is a zoonotic virus, which means it is passed between animals and humans, specifically from camels. Researchers suspect that the virus originated in bats who transmitted the virus some time ago.

This virus does not pass easily from person to person, and human transmission has been limited, notes the WHO. (9) Since the first reported case, there have been 2,494 laboratory-confirmed cases of MERS from 27 countries, resulting in 858 deaths, per the WHO. (10)

This virus was first reported at the end of 2019 in China, where it was associated with an outbreak of pneumonia. The first case confirmed in the United States was reported on January 21, 2020. The patient had recently traveled to Wuhan, China, where the outbreak first began, according to the CDC. (11) By April 16, 2020, there were more than 2 million confirmed cases of COVID-19 in 185 different countries, with New York City as the epicenter, where more than 118,000 cases and approximately 10,900 deaths had been confirmed, according to the Johns Hopkins University.

It’s suspected that the virus began in bats — the genetic sequence is similar to other known coronaviruses that begin with that mammal — but experts believe it may have been transmitted to humans by an animal called a pangolin. These long-snouted, ant-eating mammals are often used in traditional Chinese medicine, according to an article published in February 2020 in Nature. (12)

COVID-19 is transmitted from person to person through tiny droplets, which can spread when a person infected with the virus coughs or exhales. Approximately one out of every five infected people needs hospital care. (3)

On January 31, 2020, the U.S. Department of Health and Human Services declared a public health emergency (PHE) for the United States to aid the nation’s healthcare community in responding to COVID-19. (13) The outbreak was declared a global pandemic on March 11, 2020, defined as “the worldwide spread of a new disease,” because of the alarming levels of the spread and the severity of COVID-19, as well as the alarming levels of inaction, according to Tedros Adhanom Ghedbreyesus, the director general of WHO. (14)

The four most common coronaviruses — 229E, NL63, OC43, and HKU1 — did not start in animals, but use humans as their natural hosts.

SARS, MERS, and SARS-CoV-2 are zoonotic, which means they are transmitted between animals and people. Experts estimate animals are responsible for about 60 percent of human infectious diseases. The viruses commonly circulate in animals. In fact, several known coronaviruses are currently circulating in animals but have not yet infected humans, according to the WHO. (15)

In birds, bats, and other animals, influenza viruses can replicate and be transmitted to a new host without causing any severe disease. This transmission can be to a different species. When a virus is transmitted between animals and humans, it’s called a spillover event, notes TuftsNow. (16)

The majority of people will become infected with a human coronavirus at some point in their lives. Usually this doesn’t pose a major health risk. It often causes a mild to moderate upper-respiratory infection, like a cold. Sometimes these can be more serious, however, and lead to bronchitis and pneumonia.

The risk of catching a coronavirus typically peaks in the winter and drops in the spring and summer, though this may not be the case with COVID-19. According to a report from the National Academies of Sciences, Engineering, and Medicine, there is no evidence that summer weather will interfere with the spread of COVID-19. (17)

The report pointed out that there has been rapid virus spread in countries currently experiencing “summer” climates, such as Australia and Iran. (17)

With COVID-19, people with the highest risk are those who have close exposure to a person infected with the virus. COVID-19 is spread through respiratory droplets expelled when an infected person coughs, sneezes, or talks, which is why experts recommend staying at least six feet away from a person who is sick. Research suggests that people may spread the virus even if they don’t show any symptoms.

It’s also possible that COVID-19 can be spread by a person touching a surface or object that has the virus on it and then touching their own mouth, nose, or eyes, notes the CDC. (18)

The way COVID-19 spreads is similar to how the common cold — a much milder viral infection — is transmitted. Children younger than 6 years old are at greatest risk for catching the common cold, but most adults have two or three colds every year, notes the Mayo Clinic. (19)

Risk of Developing a Severe Coronavirus

The groups at a higher risk for developing severe illness from COVID-19 include adults over the age of 65 as well as people with the below preexisting conditions: (20)

• Chronic lung disease
• Asthma
• Serious heart conditions
• Severe obesity
• Diabetes
• Liver disease

Initial reports suggest that infants, children, and adolescents under the age of 18 are less likely to have a severe case of COVID-19. (21)

The symptoms of a coronavirus can vary depending on the level of the infection. According to the CDC, a mild to moderate upper respiratory infection may include the following: (22)

• Runny nose
• Headache
• Cough
• Sore throat
• Fever
• Feeling poorly in general

More severe infections that turn into bronchitis or pneumonia can cause these symptoms:

• Fever
• Cough with mucus
• Shortness of breath or labored breathing
• Chest pain or tightness when breathing or coughing

Symptoms of COVID-19 have ranged from mild to severe and have resulted in thousands of deaths. The most common symptoms are fever, cough, and shortness of breath. The time from exposure to onset of symptoms can vary, with the median time being 5.1 days. About 97.5 percent of people who develop symptoms after exposure will do so within 11.5 days. (23)

Many people who have mild symptoms of COVID-19 aren’t tested but instead told to recover at home and practice good respiratory and hand hygiene as well as social distancing.

If you do get tested for COVID-19, it can take anywhere from one day to a week to get your results, depending on where you live and what kind of test it is.

There is currently no specific treatment for a coronavirus. Antibiotics do not work against viruses; they are only effective in treating bacterial infections. Treating and relieving symptoms is the appropriate care, according to the WHO. (3)

People who have been exposed to COVID-19 should contact their health provider for further instruction. If you test positive for COVID-19, your doctor will instruct you on how to monitor your symptoms as well as what to do if they worsen.

People confirmed to have COVID-19 may be eligible to participate in one of the ongoing clinical trials. (24)

To minimize your chances of getting a coronavirus, including COVID-19, practice the same habits you would to avoid catching any infectious respiratory virus. Per the CDC, these include:

Follow federal and local stay-at-home orders. "Stay at home" is pretty self-explanatory: Work and engage in schooling from home if possible and don’t go anywhere that isn’t essential. Avoid social gatherings with groups of more than 10 people.

Practice social distancing. Keep at least six feet between yourself and others.

• Try not to touch your eyes, nose, and mouth with unwashed hands.
• Practice home isolation if you’re sick. Separate yourself from other people and pets in your home and use a different bathroom if possible.
• If you have to sneeze or cough, cover with a tissue and then dispose of the tissue.
• Clean and disinfect things or surfaces that you touch a lot, such as phones, doorknobs, and countertops.
• Wash your hands frequently with soap and water for at least 20 seconds. If you don’t have access to a sink, use an alcohol-based hand sanitizer with at least 60 percent alcohol.
• Cover your mouth and nose with a cloth face cover when you are around others. (25)

There is currently no approved vaccine for COVID-19, although a few pharmaceutical companies, as well as the U.S. Department of Health and Human Services, are working to expedite the development of one. (26)

Can Vitamin C or Zinc Boost the Immune System to Help Prevent Coronavirus Infection?

The answer to whether or not vitamin C, zinc, or other supplements might help your body fight off infections — like one caused by the novel coronavirus — is not a simple one. The body and the immune system need both vitamin C and zinc, as well as other nutrients, to be able to function optimally. (27) But there’s little evidence that doses above and beyond the regular daily recommended amounts will provide additional benefit.

The immune system is a complicated network of cells found in many tissues in the body (the skin, the blood, and more) that work together to fight off germs like bacteria and viruses. (28) The vitamins and nutrients our bodies get from the food we eat provide the building blocks for a lot of the cells that are part of the immune system. If you’re malnourished or not eating a healthy diet, your body might be deficient in some of these key nutrients that allow the immune system to function properly — in which case a supplement could bolster your immune response. If you’re not deficient, there’s little evidence that getting extra amounts of specific nutrients can prevent illness.

There’s some evidence that zinc supplements may help your body recover faster from the common cold, according to a review of studies published in JRSM Open in May 2017. (29) But beyond this data, which was gathered from people with the common cold, there’s no way to know if zinc would have the same effect on people with other types of viruses, such as the various types of coronaviruses.

Similarly, there’s some evidence that vitamin C supplements can shorten the duration of the common cold after someone is infected with the virus, according to a paper published in the Cochrane Database of Systematic Reviews. (30) But as with the zinc study review, this data is only from people with the common cold, so there’s no way to know if vitamin C would have the same effect against people infected with coronaviruses or other viruses.

Experts say the best way to make sure you’re getting the vitamins and nutrients your body and immune system need is by eating a healthy diet. Other ways you can help keep your immune system boosted and working properly include: keeping stress under control, getting plenty of sleep, staying active, not smoking, and managing chronic conditions.

The Ultimate Checklists for Food Items, Immunity-Boosters, and Emergency Preparedness

Planning meals ahead can help you minimize the number of trips you make outside your house during the COVID-19 pandemic. Whether your intention with your food list is to follow an eating plan like the keto diet, or to use time at home to try new recipes, it’s unlikely that a particular diet alone can prevent you from getting COVID-19. But eating healthfully may shore up your immune system, so be sure to stock your pantry with foods that contain essential vitamins and nutrients. Refer to the articles below!

Must-Know Telemedicine Info

An increasing number of healthcare practitioners are offering online appointments in response to the COVID-19 pandemic, in accordance with recent CDC recommendations to provide telemedicine options to patients.

Online appointments can lower the risk of COVID-19 transmission in doctors’ waiting rooms, where small spaces may make proper social distancing difficult. Remote visits can also help reduce the strain on healthcare providers and facilities by allowing a greater number of patients to be seen.

Telemedicine is not a substitute for emergency care and cannot be used to test for COVID-19; it’s best for non-urgent situations in which physical exams, samples, or X-rays likely won’t be necessary. Check with your healthcare provider to see what they recommend should you fall ill or if you have symptoms.

The Latest COVID-19 News

Ever since the initial discovery of the novel coronavirus in Wuhan and the WHO’s eventual declaration of a pandemic, keeping up with the deluge of related news stories can feel overwhelming. Referring to trusted sources such as your local health department, or news outlets that cite accredited public health experts, will help you separate the facts from the fiction.

You can also sign up for Everyday Health’s daily Coronavirus Updates newsletter or check out our daily coronavirus alert for the latest need-to-know news. For up-to-date facts and figures regarding the coronavirus in your area, refer to your local health department’s website. If you’re in the United States, the CDC has a list of state and territorial health departments.

Coping With Chronic Health Conditions

Since SARS-CoV-2 is a new coronavirus, it’s not yet fully understood how it interacts with other health conditions. The CDC notes, however, that certain groups of people are at a higher risk of developing severe illness related to COVID-19, including those with preexisting medical conditions. These conditions may include: (20)

• Chronic lung disease
• Moderate to severe asthma
• Heart disease
• HIV or AIDS
• Obesity (a body mass index of 40 or higher)
• Type 1 and type 2 diabetes
• Chronic kidney disease
• Liver disease

If you are living with a chronic condition, take extra care to follow all the CDC-recommended precautions against the coronavirus outlined above.

Self-Care Resources to Help You Stay Grounded

Staying home all day may be one of the best ways to stop the spread of COVID-19, but it can also wreak havoc on your mental health. Many of the activities that we rely on as self-care practices — think yoga classes, gym sessions, and time spent with friends — have been suspended or canceled for the foreseeable future. And with the constant news coverage about the impact of the coronavirus, which rarely seems to be good, it can be easy to feel overwhelmed.

While you may not be able to participate in your usual activities and events that could help at a time like this, you can still cultivate your own well-being by developing and implementing a self-care regimen and sticking to it. Whether that means limiting your social media consumption, committing to a form of exercise you enjoy, or simply setting a sleeping schedule and sticking to it, there has never been a more critical time to ensure you’re looking after yourself and engaging in healthy self-care practices.

Build Resilience and Fight Stress to Stay Strong

Even if you have an established self-care routine, stress is an inevitable part of life. And between mass layoffs, a struggling economy, and the spread of COVID-19 throughout so many communities, it’s completely normal to experience stress as a result of the coronavirus pandemic. In fact, a joint poll carried out by ABC News and the Washington Post found that 77 percent of respondents reported that their lives had been disrupted in some way by the virus, and 70 percent reported that the pandemic was a source of stress. It seems clear that however the COVID-19 pandemic progresses, the United States will have to be as resilient as ever in order to return to normalcy.

Everyday Health partnered with researchers at the Ohio State University in Columbus to create two special reports, one on the impact of stress in the lives of Americans and one examining the importance of resilience in weathering tough situations. The COVID-19 pandemic is the perfect time to revisit these reports to learn more about how to manage stressful events and cultivate your personal resilience.

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