News of the new coronavirus (called 2019 Novel Coronavirus) has prompted concern about risk of transmission in the United States. Although influenza viruses and coronaviruses have similar symptoms, the risk of catching the flu in the United States remains far greater. Here's what you need to know about the flu vs. coronaviruses.  

Yale New Haven Health's walk-in/urgent care centers offer convenient, professional medical attention for non-life threatening conditions including the flu and common cold. If you live in Connecticut, our Video Care OnDemand service provides video access to clinicians for minor medical concerns.

Influenza (Flu) Overview

The flu is a contagious respiratory illness caused by influenza viruses that infect the nose, throat and sometimes the lungs. Older people, young children and people with certain chronic conditions (asthma, heart disease, diabetes, among others) are at increased risk for serious complications, including pneumonia. The best way to prevent flu is by getting a flu vaccine every year.

Common Questions and Answers about the flu

How do I know if I have the flu?

Flu symptoms are more intense than those associated with a cold and usually come on suddenly, including a fever higher than 100.5 degrees, extreme exhaustion, severe muscle or body aches, a dry cough and chills.

How long is someone with the flu contagious?

The flu can spread person-to-person before symptoms are apparent as well as while you are sick. People with the flu are most contagious in the first 3-4 days after their illness begins. However, healthy adults may be able to infect others 1 day before symptoms develop and up to 5-7 days after becoming sick. Young children and people with weakened immune systems might be able to infect others for an even longer time.

How do I prevent the flu?

The most important step in preventing the flu every year is to get a flu shot. It takes two weeks for flu-preventing antibodies to develop after vaccination. You should also take everyday preventive actions (e.g., staying away from people who are sick, covering coughs and sneezes and frequent handwashing) to help slow the spread of germs.

When should I see a doctor for the flu?

If you think you have the flu, seeing a doctor may help you get better faster and prevent major complications. Those who are considered "high-risk" (i.e., you are 65+, have a chronic medical condition, have a compromised immune system, or are pregnant) should see a doctor at the first signs of the flu. Yale New Haven Health and PhysicianOne Urgent Care operate urgent/walk-in care centers throughout Connecticut and New York. Connecticut residents can also schedule a visit through our Video Care OnDemand service.

Coronavirus Overview

Human coronaviruses are common throughout the world. The most recent coronavirus, 2019 Novel Coronavirus, was first identified in Wuhan, China and is associated with mild-to-severe respiratory illness with fever and cough. At this time, the threat of contracting the virus in the United States and Connecticut is very low.

Questions and Answers about the 2019 Novel Coronavirus

What are coronaviruses?

Coronaviruses are a group of viruses that are common in both humans and animals that usually cause mild-to-moderate respiratory illnesses. The source of the 2019-nCoV is suspected to be animals in an open air market and is possibly a previously unrecognized bat coronavirus. It appears to cause a more severe illness progressing to pneumonia.

This is a rapidly evolving situation. More is being learned about this new virus every day and updates are available on the CDC website.

What are the symptoms of this coronavirus infection?

Common human coronaviruses usually cause mild-to-moderate upper-respiratory tract illnesses, like the common cold. Zoonotic coronaviruses, originally from bats (e.g., MERS-CoV, SARS-CoV), can cause more severe symptoms and often progress to pneumonia.

What is the risk of this coronavirus infection spreading in the United States?

Yale New Haven Health is monitoring the progression of the virus to keep our patients and staff safe. At this time, the risk of becoming infected with this new coronavirus in the United States is very low.

Coronavirus vs. the flu: Which is a greater threat?

To date, there have been 15 confirmed cases of this new coronavirus in the United States, and 0 confirmed in Connecticut. In contrast, there have been at least 15-million flu illnesses reported in the United States since the start of flu season in October 2019.

Has Yale New Haven Health treated a patient with this coronavirus?

Yale New Haven Health is not currently treating any patients with confirmed 2019 novel coronavirus. However, we have seen an exceptionally high number of patients with of influenza this winter. Each patient presenting with flu-like symptoms is evaluated thoroughly to prescribe a care plan. Yale New Haven Health also encourages those with respiratory infections to use any of the walk-in clinics listed on our website as an alternative to our emergency department. If you have traveled in China during the past two weeks and are now ill with a possible respiratory tract infection, please call your doctor, or the clinic, first so that you can be cared for in a safe manner.

How will Yale New Haven Health protect patients, visitors, and staff from coronavirus?

At Yale New Haven Health we are employing protective measures to ensure the well-being of both our patients and staff. We are asking our patients who are experiencing upper-respiratory tract infections about their travels, specifically if they have been to China or elsewhere across the globe during the past few weeks. We are taking a cautionary approach by putting masks on those individuals and placing them in a private room to ensure the safety or our patients and staff.

Where can I get more information about coronavirus?

If you have questions about coronavirus, talk with your doctor. More information on coronavirus is available from the CDC:


Note: This page was last reviewed February 3, 2020. For additional information, refer to the CDC's website