Patients with uncomplicated flu seldom develop shortness of breath in the 4 to 8 days after symptoms start, and those with mild dyspnea typically improve gradually. Influenza that develops into viral pneumonia with labored breathing usually does so very quickly.

Could shortness of breath be a symptom of COVID-19?

Feeling breathless with COVID-19 usually means the lungs are infected. If the coronavirus has caused pneumonia, then — depending on how serious it is — the lungs may struggle to get enough oxygen into the bloodstream. This is a problem because oxygen is an essential nutrient for every organ in the body.

What are the similarities between flu and COVID-19?

Both COVID-19 and flu can have varying degrees of signs and symptoms, ranging from no symptoms (asymptomatic) to severe symptoms. Common symptoms that COVID-19 and flu share include:

• Fever or feeling feverish/chills
• Cough
• Shortness of breath or difficulty breathing
• Fatigue (tiredness)
• Sore throat