Editor’s Note: This article from March 2020 is out of date. For the latest information about COVID-19, see realhealthmag.com/tag/coronavirus. For more news about the coronavirus and COVID-19, see our sister site, COVIDHealth.com.

Although older people, those with other health conditions and people with compromised immune systems remain most at risk of severe illness from the new coronavirus, everyone should be vigilant.

Click here for a Real Health slideshow in English on seven ways to prevent the spread of the new coronavirus. Click here for a Tu Salud slideshow in Spanish.

A month after the new coronavirus respiratory disease known as COVID-19 came to public attention, researchers and public health official are continuing to learn about its spread, its mortality rate and who is most likely to become seriously ill.

Although much remains unknown, it’s clear that elderly people, those with other health conditions and people with compromised immune systems have a higher likelihood of severe illness. This includes people with cardiovascular disease, cancer and HIV. But taking some basic precautions can help keep you safe.

COVID-19 Basics 

As of March 2, there were 43 cases of COVID-19 detected in the United States, according to the Centers for Disease Control and Prevention (CDC). In addition, there have been 48 cases among people brought back to the U.S., mostly from the Diamond Princess cruise ship. The virus now appears to be spreading locally within communities. Worldwide, more than 87,000 cases have been reported, according to the World Health Organization. Most of these are in China, but 58 countries have now seen cases.

The mortality rate for COVID-19 is thought to be around 2.5%, based on the numbers reported in the hardest-hit areas of China. This is substantially higher than the typical seasonal flu (around 0.1%), but much lower that the death rates of the SARS (severe acute respiratory syndrome) and MERS (Middle East respiratory syndrome) coronaviruses, at around 10% and 30%, respectively.


However, the true COVID-19 mortality rate is not yet known because it is unclear how many people have contracted the new virus. If a large number of people have no or mild symptoms and never seek medical attention, the pool of infected people could be much larger and the death rate could be much lower. Receiving supportive treatment earlier in the course of the disease also lowers the risk of death.

A majority of people with COVID-19 have mild symptoms including fever, cough and shortness of breath. Around 20% develop more severe illness, including pneumonia and acute respiratory distress syndrome, which may require intensive care and in some cases mechanical ventilation.

But not everyone who contracts the virus is at equal risk. According to a recent study of more than 45,000 confirmed cases in China, people with coexisting conditions had higher death rates: 5.6% for cancer, 6.0% for hypertension (high blood pressure), 6.3% for chronic respiratory disease, 7.3% for diabetes and 10.5% for cardiovascular disease. The greatest risk was seen among people age 80 or older, at 14.8%. Children, on the other hand, seem to have mild disease that is rarely fatal.

Experts do not yet know how long someone can transmit the coronavirus (officially known as SARS-CoV-2) before they develop symptoms or after they recover. It is also unclear whether the virus can linger in the body and later relapse; whether it confers immunity and, if so, for how long; or the likelihood of becoming infected again.

Researchers are hard at work to develop treatments for COVID-19 and a vaccine for SARS-CoV-2. Certain HIV medications have shown activity against the coronavirus. Clinical trials of Gilead Sciences’ antiviral drug remdesivir are currently underway in China and at the University of Nebraska Medical Center in Omaha—home of the CDC’s largest biocontainment unit—where some people who contracted the virus overseas are being treated. A vaccine from Moderna Therapeutics has been sent to the National Institute of Allergy and Infectious Diseases for the first Phase I study. However, human trials are expected to at last at least a year before a vaccine is ready for widespread use.

Who Is at Extra Risk? 

Compared with the general population, people with compromised immunity and certain coexisting conditions are at higher risk of developing more serious COVID-19 illness. For example, many cancer patients use chemotherapy medications that can cause neutropenia, or depletion of immune system white blood cells that fight infection.

Editor’s note: An earlier version of this article stated that people with compromised immunity are at greater risk of contracting the coronavirus, in addition to developing more serious disease. While this is the case for many infections, there currently are not enough data to say whether immunocompromised people, including those living with HIV or being treated for cancer, are at greater risk of catching the new virus.

“When you look at who’s been most profoundly ill, it tends to be people who are older, in their 60s, 70s and 80s. As you get older, your immune system doesn’t function as well,” says Steve Pergam, MD, MPH, of the Vaccine and Infectious Disease Division at Fred Hutchinson Cancer Research Center. “For cancer patients on chemotherapy, people with solid organ transplants or bone marrow transplants and those who use high-dose steroids for autoimmune diseases, the risk will likely be more severe.”

Cardiovascular disease was one of the strongest risk factors for severe COVID-19 in the Chinese study mentioned above. Hypertension and diabetes, which are more common among African Americans and Latinos, also raise the risk.

People with hepatitis C—especially those who have not been cured with antiviral treatment—have a higher rate of heart disease. People with non-alcoholic fatty liver disease (NAFLD) or its more severe form, nonalcoholic steatohepatitis (NASH), often have cardiovascular risk factors including metabolic syndrome, obesity and diabetes.

For people living with HIV, “it’s all based on level of immune suppression,” Pergam says. “For an HIV patient who is on stable antiretroviral therapy and has a normal CD4 count, their risk may be slightly increased. People often lump HIV patients with other immunosuppressed patients, but HIV is a different disease than it was years ago. For people who have a reconstituted immune system because of treatment, I think the risk is not going to be tremendously different.”

Taking Precautions 

Experts recommend that everyone take common-sense precautions to prevent transmission of the new coronavirus—the same ones recommended to prevent seasonal flu: 

  • Avoid close contact—meaning within about six feet—with people who have a cough or other respiratory symptoms.
  • Wash your hands with soap and water thoroughly and often for at least 20 seconds.
  • Use alcohol-based hand sanitizer when soap and water are unavailable.
  • Avoid touching your eyes, nose and mouth.
  • Healthy people do not need to routinely wear facemasks to prevent infection, but use a mask if you are caring for someone who is ill.
  • Get the flu vaccine. Older people should also consider getting vaccinated against pneumonia.

If you are ill: 

  • Cough or sneeze into a tissue or your bent elbow, and immediately dispose of tissues in the trash.
  • Avoid close contact with others.
  • Stay home if you are sick.
  • If you think you may have been exposed to the coronavirus, contact a healthcare provider promptly if you develop a fever, cough or difficulty breathing.
  • Before you go to a clinic or hospital, call ahead so the staff can take appropriate precautions.
  • Wearing a facemask can stop the spread of droplets that can transmit the virus to others.

Older individuals and people cardiovascular disease, HIV, liver disease or other conditions may benefit from extra precautions.

“I advise people to have hand sanitizer wherever they go and use it frequently in public places—I have it in my pocket all the time. Wash your hands with soap and water long enough to sing the Happy Birthday song,” Pergam advises.

“I always talk with patients about the idea of social distancing. I’m not saying you can’t live your life as a normal person. But you don’t have to go out to dinner when a restaurant is super crowded—you might eat a little earlier or you might order in,” he continues. “If you’re having friends or family over, ask them if they have any symptoms. Have a hand gel dispenser at your front door and make sure everybody uses it. Make sure to tell friends and family that they should be up to date on their vaccines for other things.”

People who need prescription medications should try to have a supply to last at least a couple weeks and preferably a few months. Shortages could happen because the ingredients for many drugs—especially generics—are produced in China. Pergam acknowledges that this can be difficult because of cost and insurance restrictions.

It’s also a good idea to have at least a two-week supply of food, water, cleaning supplies and other household necessities on hand. And don’t forget to stock up on pet food. You may be able to goods delivered to avoid going to stores. Or ask a friend or family member without compromised immunity for help.

As the COVID-19 outbreak becomes more widespread, “disruption to everyday life might be severe,” according to Nancy Messonnier, director of CDC’s National Center for Immunization and Respiratory Diseases, who advises business to explore remote work options and families to consider plans in case schools close.

“Talk to your employer about opportunities to work from home,” Pergam advises. “And have them remind everyone you work with not to come to work sick.”

Stay in communication with your health care providers and keep up to date on new developments. Let them know if you have questions or concerns, especially if you have new symptoms or were recently exposed to someone who is ill.

“The biggest thing to get across is, don’t panic,” Pergam says. "We’re all expecting this to be a prolonged and complicated process. The best thing people can do is focus on ways that they can protect themselves, because those small things can be enough to provide an extra layer of protection for everyone.

U.S. and global coronavirus tracker from Johns Hopkins University

CDC COVID-19 website