Last year, for the 2019-2020 flu season, the Centers for Disease Control and Prevention (CDC) (www.ismp.org/ext/556) estimated that there were close to 56 million cases of influenza in the US. This resulted in 26 million people seeking medical care; 740,000 people needing to be hospitalized; and 62,000 deaths. These numbers are just from the influenza virus alone, and do not include COVID-19 cases.

The flu is a respiratory virus which can spread easily from person to person when they are in close contact with each other. Sneezing and coughing near someone without covering your nose or mouth play a big role in spreading the flu. Additionally, surfaces that are contaminated and then touched by others contribute to spreading the disease. This is very similar to how COVID-19 is spread, but the illnesses are caused by different viruses. 

Symptoms of the flu and COVID-19 are very similar and may be difficult to tell apart. In addition, some people may become infected with other viruses that cause very mild symptoms. In this case, the culprit may be the common cold. So, how can you tell the difference?

The common cold usually develops gradually. Most people have a runny or stuffy nose, and/or a cough. In general, most people recover from a cold without developing any serious health complications. The flu, on the other hand, begins quickly and includes a fever, body aches, a headache, and fatigue. The person may or may not have a stuffy nose, cough, or sore throat. COVID-19 has many of the same symptoms as the flu, but there are a few differences that stand out. For example, people with COVID-19 have often reported a change in or loss of taste or smell and shortness of breath. See Table 1 for a comparison of cold, flu, and COVID-19 symptoms.

Complications from having the flu or COVID-19 are also similar and can include getting pneumonia and other serious breathing problems; severe infections (sepsis); heart injury (e.g., heart attack or stroke); kidney failure; and worsening of a chronic health condition

(e.g., diabetes). People who are over the age of 65, pregnant women, and those with chronic health conditions are at an increased risk of experiencing these complications.

However, there are some important differences between the flu and COVID-19 (www.ismp.org/ext/557).

Table 1

When do symptoms appear?

Flu: Symptoms appear 1 to 4 days after being infected.

COVID-19: Symptoms appear 2 to 14 days after being infected (typically 5 days).

How long can someone spread the virus?

Flu: An infected person can spread the virus 1 day before symptoms appear; most contagious on days 3-4, but up to 7 days after the start of the illness.

COVID-19: An infected person can spread the virus 2 days before symptoms appear; up to 10 days after the first symptom appears or 10 days after testing positive.

Who is at greatest risk for developing severe illness or complications from the virus?

Flu: Young children are at higher risk of developing severe illness from the flu compared to COVID-19.

COVID-19: School-aged children have a higher risk of developing Multisystem Inflammatory Syndrome in Children (MIS-C), a rare but severe complication of COVID-19.

What are some complications from having the virus?

Flu: Most people will recover within a few days to 2 weeks; some will develop complications such as pneumonia and other serious breathing problems; severe infections; heart injury; and kidney failure.

COVID-19: Most people with a mild case will recover within 2 weeks; some will develop complications similar to the flu but may also include blood clots in the veins and arteries of the lungs, heart, legs, and brain; and MIS-C.

What are the approved treatments?

Flu: Doctors may prescribe an oral antiviral medicine to treat the flu (i.e., Tamiflu [oseltamivir]).

COVID-19: Treatment options are being investigated. Recently, the US Food and Drug Administration (FDA) has approved the antiviral medicine, Veklury (remdesivir), for

intravenous (IV) use to treat hospitalized adults and older children with COVID-19. The FDA has also issued an Emergency Use Authorization (EUA) for Veklury to allow its use to treat younger children (weighing at least 3.5 kg) who are hospitalized with COVID-19.

Here’s what you can do: The CDC is recommending that everyone needs to continue to follow safety recommendations to help stop the spread of COVID-19. In addition, it is especially important for people to get the flu vaccine this year so that more people are protected. The flu vaccine is recommended for everyone 6 months and older. Even if you received a flu vaccine last season, you would still need a flu vaccine this season for the best protection. The CDC recommends getting the flu vaccine by the end of October. However, vaccination will continue to be offered throughout the flu season. It takes about 2 weeks for your body to develop immune protection from the vaccine that will protect you against the flu. This will help reduce the number of people requiring medical care from the flu and save resources for the care of COVID-19 patients.

This flu season, remember these three important safety tips:

1) Mask up: Wear a mask covering both your nose and mouth anytime you are out in public and cannot maintain social distancing (6 feet apart).

2) Lather up: Wash your hands often with soap and water (or use an alcohol-based hand sanitizer when soap and water are unavailable).

3) Roll up (your sleeve): Do your part in protecting yourself, your family, and community—get your annual flu vaccine.