In general, it has been my experience with flu that it's about 6 weeks ramp up time, 2-3 months of high prevalence, and about 6 weeks wind down time. But there's a vaccine for flu, and much of the population has some immunity to it, plus the incubation period is much shorter, maybe 2-4 days. The incubation period for coronavirus really IS up to 14 days, and a person can be shedding virus and spreading it for quite a few days before they feel sick, if indeed they ever DO feel sick.
We are going to follow the path of Italy, Spain (and Wuhan until about a month after the strict lockdown was put into effect), not of most of China. Our political system will not allow the brutal lockdown that was able to be enforced in China. What we need is for Trump to order a complete and total lockdown, call out the Army to enforce it, and to set up field hospitals. We need ALL our governors to order complete and total lockdown, call out the state National Guards to enforce it, and to set up field hospitals. It's almost too late. But Trump won't, and by the time the individual governors do, it will be too late.
We're going to have our hospital system collapsing in about 3-4 weeks, with rationing of ventilators according to patient age and risk factors. Over 55? Have diabetes, high blood pressure, some form of cancer? No vent for you, just sedation. The hospital hallways will be blocked with stacked corpses.
Yes, many people will have mild cases, especially the young. But with 360 million people, expect at least 70% (probably 90%) to become infected, and with a 2% death rate overall, expect 6 million dead, concentrated largely among the elderly and vulnerable. If you have a parent in a nursing home, and can possibly bring them home, do so. Otherwise, they are likely to get it in the home, unless homes lock the caregivers in with the patients, and I haven't heard of any of them doing it.
I'm over 55, and am on cancer treatment, no functioning immune system. If I get it, I'm dead. I stocked the house over the past two months with enough food and supplies for more than 3 months, sent my healthy teenager to live with my healthy young adult son the minute school closed, and am on extraordinarily strict lockdown with my husband and daughter (who is on immunosuppressive medication). Another 5 days, and we will know we made it in time. Meanwhile, a friend who has been on lockdown for 9 days, just came down with the virus. He's over 60, and has risk factors. I hope he makes it.
From China, approximate death rate for the young is 1:500. For people in their 50's, 1%. In their 60s, 5%. In their 70's, about 10%. In their 80's, almost 20%. They didn't mention for people in their 90s. Realize that many, many people simply died at home and were cremated (the crematoria were running 24/7 at top capacity for a couple of months, with the cause of death as "died at home") Those deaths may not be included in these statistics. I think that Italy's death rate is running closer to 4%, because they're honestly recording the deaths as coronavirus deaths.
Your mileage may vary, according to individual risk factors, and the availability of an ICU bed and a ventilator.
If you have risk factors or are an older adult, STAY AT HOME AND DO NOT GO ANYWHERE! Keep your entire household at home, do not host visitors, do not go out.