As I am writing this, there are throngs of people at my apartment building's pool -- no masks and no physical distancing.

This wasn't supposed to happen. I'm a 20-something myself, and during the early days of the pandemic I wrote an open letter to my generation explaining why they should be staying away from crowded beaches and staying home. I cited reliable facts and figures about the pandemic and, pointing to Italy, warned of the consequences of not taking it seriously.

After it was picked up by CNN, my letter reached a national audience. In the face of conflicting public health advice, I hoped that highlighting the data itself would change hearts and minds.

Five months later, it is clear that neither my piece nor the many Covid-19 public health dashboards have persuaded many of my peers. I'm struggling to understand why.

This is not just wounded pride. Young people between 20 and 40 are a significant portion of the growing number of cases, and many more may be contagious even if they don't show any symptoms. If we want to stop the virus and re-open our schools, shops and restaurants, we need to get young people on board with masks and social distancing.

Why aren't facts enough to do this? I don't have definitive answers. But with five months to ponder it, I have some ideas.

First, public health campaigns that promote total elimination of risk don't work well -- especially for young people. Think about abstinence-only sex education.

It's been proven to be ineffective. But it's also associated with worse outcomes because it deprives kids of opportunities to understand how to reduce risks if they do choose to have sex. Similarly, simply bombarding young people with #StayHome memes likely won't eliminate risky behavior.

In fact, a 30-year-old man who thought Covid-19 was a hoax recently died after attending a "Covid party" in Texas. Clearly, some young people are not getting good information on mitigating risk.

We're actually in a worse position than those teaching abstinence-only sex education, because unlike the risk of STDs or teen pregnancy, the risk of Covid-19 was unknown just a few months ago.

The pandemic has progressed with speed and -- given the mixed messaging from public officials -- chaos. It's no surprise that when we tell young people they can either stay at home or risk serious danger by leaving the house, they choose to leave the house.

Secondly, peer pressure during quarantine is enormous. I feel it daily. How can so many people be posting about their trip to the lake, dinners at fancy restaurants and "darties" -- daytime parties -- while I sit at home?

Lastly, young people have always had a strong sense of invincibility. Gary L. Wenk, a psychology and neuroscience professor at Ohio State University, reports that feelings of immortality hinge on the fact that their frontal lobes are not fully developed, or myelinated. This process is completed between the ages of 25 and 30.

People see more of their mortality as they age -- young people simply aren't primed for death. And during a pandemic,