Roughly 80% of coronavirus infections are thought to be "mild," but symptoms in those cases are often still serious and painful.

Mild COVID-19 cases usually involve fevers and dry coughs.

If you are experiencing these symptoms, self-isolate and call your doctor.

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People who get "mild" cases of COVID-19 often still experience a range of uncomfortable and even painful symptoms.

Cases in general are categorized as "asymptomatic," "mild," "severe," or "critical." Studies have suggested that about 80% of infections by the novel coronavirus are mild, but that simply refers to people who don't need to be hospitalized. Mild cases can also develop into severe cases if the infections worsen.

Mild COVID-19 cases are often worse than a cold or flu — they're usually marked by about two weeks of fevers and dry coughs. Less common but still possible are a handful of other symptoms including fluid in the lungs, shortness of breath, headaches, muscle soreness, fatigue, and gastrointestinal symptoms.

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Research suggests that on average, the virus' incubation period is about five days. Nearly 98% of patients develop symptoms within 11.5 days, though about 1% start showing symptoms after 14 days.

Within a few days of symptoms appearing, those infected may experience shortness of breath. Many have headaches. About 40% of patients' lungs begin to produce fluid.

If you're experiencing symptoms of coronavirus, you should call your doctor before going to a clinic or hospital. Your doctor can then direct you about whether to get tested and recommend over-the-counter medications. It's also important to self-isolate, rest, and take in lots of fluids.

Here's how symptoms progress among typical patients day by day, according to the Chinese CDC:

Day 1 (after the incubation period): Patients run a fever. They may also experience fatigue, muscle pain, and a dry cough. Some may have had diarrhea or nausea one to two days before.

Day 5: Patients may have difficulty breathing — especially if they are older or have a preexisting health condition.

Day 8: At this point, patients with severe cases (15%, according to a study from the Chinese CDC) may develop acute respiratory distress syndrome, an illness that occurs when fluid builds up the lungs. ARDS is often fatal.

Day 10: If patients have worsening symptoms, this is the time in the disease's progression when they're most likely to be admitted to an intensive-care unit. These patients probably have more abdominal pain and appetite loss than patients with milder cases.

Day 17: On average, people who recover from the virus are discharged from the hospital after 2 1/2 weeks.

The disease's symptoms are more severe for older people and those with preexisting conditions, such as heart disease, diabetes, high blood pressure, and cancer.