According to the Ohio Department of Health, the following are key difference between the flu and COVID-19:

When symptoms begin:

Flu: One to four days after the infections starts.

COVID-19: As early as two days after the infection or as late as 14 days.

Complications:

Flu: Complications can happen, but are less likely due to immunity built up over time.

COVID-19: Because coronavirus is new most people have no immunity. Severe respiratory complications can happen extremely quickly.

Symptoms:

Flu: Some signs include fever, cough, shortness of breath, fatigue, runny nose, headache and body aches.

COVID-19: Some symptoms are similar to the flu, but those with coronavirus sometimes experience a loss a taste or smell.

Spread:

Flu: Flu can spread from person to person, between people in close contact and by air droplets.

COVID-19: Coronavirus can spread quicker and easier between people than the flu, sometimes resulting in superspreader events. It also is more contagious among certain age groups and certain people.