5 Things Everyone Should Know About the Coronavirus Outbreak

Strict precautions could save lives as experts work on solutions.

Pipette adding fluid to one of several test tubes, possibly to test for COVID-19

News about the coronavirus is still evolving, while doctors say the best advice is to follow public health directives and take care of yourself.

Credit: Getty Images

[Originally published: January 23, 2020. Updated: May 27, 2020.] 

COVID-19 has been changing daily life in the United States as SARS-CoV-2, the virus spreading the disease, has swept across the country, forcing activities to be cancelled and schools and businesses to close. The U.S. declared a national emergency in mid-March, and Americans have been adjusting to strict guidelines, cancelled activities and closures, and mandates to stay home. Now different parts of the country are gradually reopening and experts are focused on the best ways to do that safely. 

SARS-CoV-2 is a virus that scientists haven’t seen before. Like other viruses, it is believed to have started in animals and spread to humans. Animal-to-person spread was suspected after the initial outbreak in December among people who had a link to a large seafood and live animal market in Wuhan, China.

By January, clusters of cases of a mysterious pneumonia were being reported in Wuhan, and in the following weeks person-to-person spread of the virus was reported around the world. In early March, the World Health Organization (WHO) declared COVID-19 a pandemic—a disease outbreak occurring over a wide geographic area and affecting an exceptionally high proportion of the population.

Scientists and public health officials are working as quickly as possible to find answers to key questions about how the disease is transmitted and why some cases are more severe than others, while they investigate treatments and a potential vaccine.

Below is a list of five things you should know about the coronavirus outbreak.

1. What we know about COVID-19 is changing rapidly

The number of people infected by the disease changes every day. While the impact of the disease varies by location, there are now almost 5.5 million confirmed cases of people with COVID-19 around the globe and almost 350,000 people have died from the disease, according to the WHO. (While some news sources report different numbers, the WHO provides official counts of confirmed cases once a day.)

The U.S. currently has the highest number of cases of any country in the world. While some pockets of the U.S., including New York, are reporting a decrease in new cases, the overall numbers continue to rise. It’s not clear how the numbers will change as parts of the country loosen the restrictions that have been in place. The Centers for Disease Control and Prevention (CDC) provides a rough picture of the outbreak in the U.S. here, currently putting the total confirmed and probable cases at almost 1.7 million, and estimating almost 100,000 deaths. (If there any discrepancies, data provided by state public health departments should be considered the most up to date, according to the agency). 

The term coronavirus includes a family of seven known viruses that cause respiratory tract illnesses that range from the common cold to such potentially deadly illnesses as severe acute respiratory syndrome (SARS), which killed almost 800 people during an epidemic that occurred in 2002 and 2003. COVID-19 is the first pandemic known to be caused by the emergence of a new coronavirus—novel influenza viruses caused four pandemics in the last century (which is why the response to the new disease is being adapted from existing guidance developed in anticipation of an influenza pandemic). 

According to the CDC, reported COVID-19 illnesses have ranged from mild (with no reported symptoms in some cases) to severe, including illness resulting in death. People ages 65 and older, those living in a nursing home or long-term care facility, and people of all ages with underlying health conditions seem to be at higher risk of developing serious illness. But doctors are still working to develop a complete clinical picture of COVID-19.

“I think there are two main questions,” says Richard Martinello, MD, a Yale Medicine infectious diseases specialist and medical director of infection prevention at Yale New Haven Health. “First, we need to know how this virus is transmitted between people so we can be more precise in our efforts to stop its spread. Data is needed not only to better understand when those who become ill shed the virus, but also which body fluids contain the virus and how those may contaminate surfaces and even the air surrounding them,” says Dr. Martinello. “Second, there needs to be a better understanding of the pathogenesis of the infection and resulting inflammatory response, so that knowledge can drive the development of therapeutic and preventive medications.”

More information is becoming available. A letter to the editor published in The New England Journal of Medicine in mid-March showed the virus that causes COVID-19 may be stable for several hours in aerosols (in this case, droplets from an infected person dispersed in air or gas) and for several hours to days on surfaces. Scientists who participated in the analysis found SARS-CoV-2 was detectable in aerosols for up to three hours, copper up to four hours, cardboard up to 24 hours, and plastic and stainless steel up to two to three days. While there is much to learn, scientists involved in the analysis observed that emerging evidence suggests people who are infected might be spreading the virus without recognizing, or prior to recognizing, symptoms, according to the National Institutes of Health (NIH).

But Yale Medicine Infectious Diseases specialist Jaimie Meyer, MD, MS, notes, “A lot of times people will make basic science observations in the research lab, but it takes time for us to figure out how clinically relevant it is. So, we don’t know yet know what this study means for transmissibility. Until we understand more about the granular details of how SARS-CoV-2 passes from person to person, public health dictates that people maintain social distancing, wash hands, and frequently disinfect high-touch surfaces."

2. Strict measures are critical for slowing the spread of the disease

While we still don't know how the situation will progress around COVID-19, studies of influenza have shown that pandemics begin with an “investigation” phase, followed by “recognition,” “initiation,” and “acceleration” phases, according to the CDC, and that is followed by deceleration, during which there is a decrease in illnesses. Finally, there is a "preparation" phase, where the pandemic has subsided, and public health officials monitor virus activity and prepare for possible additional waves of infection. Different parts of the U.S. have been experiencing the pandemic to different degrees, depending, in part, on the public health response.

According to the CDC, the U.S. is in an acceleration phase, when the peak of illnesses occurs. Efforts have been aimed at "flattening the curve." If you map the number of COVID-19 cases over time, the expectation is that it will peak at some point—on a graph this peak would mirror a surge in patients (which could overwhelm hospitals and health care providers). Flattening the curve would mean there would be fewer patients during that period, and hospitals would be better able to manage the demands of patients who are sick with COVID-19 and other illnesses.

Meanwhile, many places are focused on easing restrictions that have been put in place. White House guidelines for Opening Up America Again, a phased approach to help state and local officials reopen their economies, provides advice on continuing handwashing, wearing face masks, and taking other precautions during the reopening. In late May, Connecticut took the first steps toward a phased reopening by allowing people to return to offices, retail establishments, restaurants, university research laboratories, and outdoor recreation activities, as long as certain precautions are in place (restaurants can serve only outdoors, for example).  The state continues to prohibit gatherings of more than five people and direct people to wear face coverings in public when maintaining a six-foot distance is not possible.

Meanwhile, more people are being tested for the virus, and communities are hiring contact tracers to contact and support people who have had a potentially high-risk exposure to someone infected with COVID-19. A call or message from a contract tracer does not mean you have the disease, but it may be a reason to self-isolated and get tested.

3. Infection prevention is key

There are many things you can do to protect yourself and the people you interact with. As with a cold, a flu vaccine won’t protect people from developing COVID-19.  “The best thing you can do at this point is take care of yourself the way you would to prevent yourself from getting the flu,” says Yale Medicine infectious diseases specialist Joseph Vinetz, MD. “You know you can get the flu when people sneeze and cough on you, or when you touch a doorknob. Washing hands—especially before eating and touching your face, and after going to the bathroom—and avoiding other people who have flu-like symptoms are the best strategies at this point.”

The CDC also recommends the following preventive actions:

  • Wash hands with soap and water for at least 20 seconds. Dry them thoroughly with an air dryer or clean towel. If soap isn’t available, use a hand sanitizer with at least 60% alcohol.
  • Stay home if you’re sick.
  • Avoid touching nose, eyes, and mouth. Use a tissue to cover a cough or sneeze, then dispose of it in the trash.
  • Use a household wipe or spray to disinfect doorknobs, light switches, desks, keyboards, sinks, toilets, cell phones, and other objects and surfaces that are frequently touched.
  • Create a household plan of action in case someone in your house gets sick with COVID-19. You should talk with people who need to be included in your plan, plan ways to care for those who might be at greater risk for serious complications, get to know your neighbors, and make sure you and your family have a plan for caring for a sick person. This includes planning a way to separate a family member who gets sick from those who are healthy, if the need arises.
  • Wear a cloth face mask in public settings where other social distancing measures are difficult to maintain, especially in areas where there is significant community-based transmission. A cloth mask is not meant to protect the wearer from infection, but to slow the spread of the virus (if people who have the virus and do not know it wear masks, they may be less likely to transmit it to others). 

While everyone should take precautions, measures may be critical for adults over 65 years old (the risk seems to gradually increase with age starting at age 40, according to the WHO), people who live in nursing homes, and people of all ages with chronic conditions (such as diabetes, heart disease, and lung disease). 

4. Experts are working rapidly to find solutions

In the U.S., widely available testing is important in understanding how the disease is transmitted and the true infection and mortality rates. While health providers across the country are using a variety of tests—and still learning about the most accurate approach—two kinds of tests are important to know about: viral tests help diagnose a current infection and antibody tests can tell if you’ve had a previous one (it is not yet known whether COVID-19 antibodies can protect from being infected again or how long protection might last). Health care providers and state and local health departments make determinations about who should be tested. 

One recent development is the first in-home test for the coronavirus. The nasal swab kit, approved by the Food and Drug Administration (FDA) in mid-April, will be made available to health care and emergency workers who may have been exposed or have symptoms of the virus before it is released to the public at a later date.

Meanwhile, scientists are studying the virus closely. “With the new virus in a culture dish, they are looking at the biology and working to make drugs to treat it,” says Dr. Vinetz. There is also a great deal of effort underway to assess drugs in development (and some medications currently available) to determine if they are beneficial for treating patients infected with COVID-19, adds Dr. Martinello.

While no pharmaceutical products have yet been shown to be safe and effective for COVID-19, a number of existing medicines have been suggested as potential investigational therapies. In early May, the FDA issued an emergency use authorization for the investigational antiviral drug remdesivir to treat suspected or laboratory-confirmed COVID-19 in adults and children hospitalized with severe disease. There is still limited information about the safety and effectiveness of remdesivir when used for COVID-19, but preliminary studies have shown that it can shorten the time to recovery in some patients. Remdesivir is an antiviral treatment that  was previously tested in humans with Ebola virus disease and has shown promise in animal models for treating SARS and Middle Eastern Respiratory Syndrome (MERS), a deadly virus that was first reported in Saudi Arabia in 2012.

5. If you feel ill, here's what you should do

So far, information shows the severity of COVID-19 infection ranges from very mild (sometimes with no reported symptoms at all) to severe to the point of requiring hospitalization. The CDC recently expanded its list of possible symptoms of COVID-19 The symptoms can appear anywhere between 2 to 14 days after exposure, and may include: 

  • 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

This list does not include all possible symptoms. The CDC will continue to update its symptoms list as it learns more about COVID-19.

You should call your medical provider for advice if you experience these symptoms, especially if you have been in close contact with a person known to have COVID-19 or live in an area with ongoing spread of the disease. The CDC has a Coronavirus Self-Checker that may help you determine whether you should seek help.

Most people will have a mild illness and can recover at home without medical care. Seek medical attention immediately if you are at home and experience emergency warning signs, including difficulty breathing, persistent pain or pressure in the chest, new confusion or ability to arouse, or bluish lips or face. This list is not inclusive, so consult your medical provider if you notice other concerning symptoms. 

Patients and members of the community can call the Yale Medicine/Yale New Haven Health Call Center at  COVID-19 hotline of Yale New Haven Health at 203-688-1700 (toll-free, 833-484-1200) if they have questions. 

Be aware of the information and resources that are available to you

Because knowledge about the new virus is evolving rapidly, you can expect information and recommendations to change frequently. Threats like COVID-19 can lead to the circulation of misinformation, so it’s important to trust information only from reputable health organizations and government sources such as the CDC and the WHO. “The public health infrastructure in the U.S. is a critical resource for leading the federal, state, and local response,” Dr. Martinello says.

Yale Medicine doctors are advising anyone who has concerns about COVID-19 exposure or symptoms to call their primary care doctor for instructions. Doctors at Yale Medicine and Yale New Haven Health also encourage all patients to sign up for MyChart, a secure online portal that allows patients to manage and receive information about their health, and enables telehealth visits (by phone or video), which is how Yale Medicine specialists currently are delivering most care not related to COVID-19.

Health officials recognize that the outbreak has been stressful for everyone, and this can have serious impacts on mental health. If you, or someone you care about, are feeling overwhelmed with emotions like sadness, depression, or anxiety, or feel like you want to harm yourself or others, call 911, or the Substance Abuse and Mental Health Administration’s Disaster Distress Helpline: 1-800-985-5990 or text TalkWithUs to 66746. (TTY 1-800-846-8517). You can call the National Domestic Violence Hotline at 1-800-799-7233 (TTY: 1-800-787-3224.)

Click here to learn more about Yale’s research efforts and response to COVID-19.