Quickscreen Logo

How do I know if I have the flu or COVID-19?

By: Dr. Sarma Velamuri, M.D., Natalie Cheng

As flu season approaches, our community is about to face additional hurdles and challenges. During a relatively quiet year, the flu wouldn’t seem like a big deal. However, the coronavirus (COVID-19) has put most people on edge. When you start feeling unwell, you start to worry – do I have the flu....do I have the dreaded COVID-19?! How can you tell the difference between the flu and COVID-19?

To give some background on the two illnesses, both influenza (the flu) and the coronavirus (COVID-19) are respiratory illnesses that often make people feel sick because of a hyperinduction of proinflammatory cytokine production. That’s biology speak for: your body inflames the same way whether it’s the flu or coronavirus. Everyone in the medical community has been talking about the cytokine storm. The human body produces cytokines, which is why there are many similarities between flu and COVID-19 symptoms.

The Flu vs COVID-19

Influenza (the flu) and COVID-19 are caused by two separate viruses. COVID-19 may seem similar to the flu, but it is more contagious among certain populations and age groups than influenza. COVID-19 also has more superspreading events than influenza. COVID-19 can spread faster to more people, simultaneously while the flu virus is ongoing.

The main difference between the two is that people develop symptoms 1-4 days after contact with someone that has the flu. Meanwhile, COVID-19 symptoms start 5 days after being infected. At the earliest, COVID-19 symptoms can start 2 days after being infected and the latest is 14 days.

Unfortunately, none of the COVID-19 symptoms are very specific to COVID. Even though anosmia (the loss of one’s sense of smell) is seen in COVID-19, it is also seen in other diseases and conditions such as the flu, hay fever, and sinusitis. It’s interesting because anosmia has been reported as a prodrome symptom for COVID-19. A prodrome is a medical term for early signs or symptoms of an illness or health problem that appear before the major signs of symptoms start. With influenza, anosmia seems to occur concurrently with respiratory symptoms.

Currently, syndromic surveillance data on influenza positivity and anosmia is lacking at the large population level. As the flu season breaks out, our Quickscreen tool will be gathering longitudinal data for epidemiologists to study anosmia with other symptoms on a timeline with exposure and contrast COVID-19 and influenza.

In addition, it seems that a fever is seen more frequently in influenza than COVID-19. One study showed that “the rate of fever was 66% (137/207) in hospitalized influenza cases.”

Unfortunately, there can be coinfections as well – getting COVID doesn’t necessary protect a person from getting influenza. Sadly, people can get both. For those that are resistant to get a flu shot, we strongly urge you to reconsider and take the flu shot this year. According to KHN, “Young, healthy people can begin getting their flu shots in September, and elderly people and other vulnerable populations can begin in October,” said Dr. Steve Miller, chief clinical officer for insurer Cigna. The CDC has recommended that people “get a flu vaccine by the end of October,” but noted it’s not too late to get one after that because shots “can still be beneficial and vaccination should be offered throughout the flu season.” In any case, don’t wait too long to get the flu shot this year because there could be a possible shortage from overwhelming demand. At Luminare, we often hear people that have been admitted to the hospital for influenza and haven’t taken a flu shot say, “I haven’t gotten sick in my life”. Please do your part and get a flu shot this year.

What can you do?

People should treat both influenza and COVID-19 seriously. Both are communicable diseases and can be a risk. Fortunately, influenza has treatment with antivirals that can decrease the duration of symptoms. If you get symptoms of the flu, you should get tested and evaluated by a physician. Influenza testing should be added alongside COVID-19 testing. Note: If you have high risk factors, you should get tested. If you’re waiting for the COVID vaccine, you should get the flu vaccine. In any case, if you are experiencing a life-threatening emergency, please call 911.

When you consider returning to work, the process for people who tested positive for influenza are different for those who tested positive for COVID-19 since the latter is contagious and there isn’t a vaccine yet.

Ultimately, implementing syndromic surveillance for influenza even after the coronavirus pandemic is over is something all employers and schools should mandate to keep people and places safe.

Are you looking for guidance in bringing employees back to work and keeping your workplace or school safe? Contact us and we’ll help you stay safe and meet HIPAA and ADA guidelines.

About Quickscreen by Luminare

Quickscreen by Luminare is the country’s first employee self-certification system. It is an innovative COVID-19 screening tool to get your employees back to work safely. The syndromic surveillance tool is HIPAA and ADA compliant and follows OSHA and CDC guidelines. In addition, the tool is approved by the Texas Education Agency (TEA). Quickscreen can be accessed on smartphone, desktop, or tablet.

Stay Connected


Legal Disclaimer
If you are experiencing a life-threatening emergency, please call 911. This tool is provided as part of a screening so people can see if they need to be tested or not. It is updated to the best of our abilities to match the CDC.gov guidelines for COVID-19 screening. This is not intended to contradict or replace a licensed independent practitioner’s medical advice. By using this site you consent to our Privacy Policy and Use Policy.