How do we look at the new CDC guidelines that have dramatically relaxed requirements for vaccinated people? These new changes have invited quite a bit of criticism, and I think this highlights the immense challenges of public health guidelines. I certainly don't envy their job.

Overall, the pandemic in the United States is dramatically better. With widespread vaccination, the spread of virus is dropping significantly. This is seen on a macroscopic scale with the lowest levels of new infections and deaths in a long time. But I have also seen it at a more granular level; in the winter, we faced a surge of patients from nursing homes. We even had a list of nursing homes with COVID-19 outbreaks so that we could appropriately prepare ourselves. After vaccinations rolled out, our nursing home COVID positivity plummeted. We really stopped seeing elderly patients come in with COVID. Anecdotal experience doesn't carry much scientific rigor, but it matches the studies from the U.K. and Israel; vaccinations dramatically reduce spread.

So I support the CDC's recommendation to loosen restrictions for vaccinated individuals. Although variants pose unknowns, the science reinforces the safety of otherwise healthy vaccinated people trying to resume their pre-pandemic lives.

But here is the CDC's conundrum. Risk is and should be an individualized matter. Different people have different risk tolerances. This depends not just on our physical health; of course those with obesity, diabetes, cancer, or other medical conditions will want to be particularly careful. But also, our personalities are different. Some people gamble. Others buy extra disability insurance. A few buy meme stocks. We cannot expect the CDC's guidelines or even our doctor's advice to take into account every nuance of risk.

And yet, we desperately want guidelines. Schools and businesses trying to open need to plan. A lack of uniformity among different geographies or states creates confusion and skepticism. The average person who doesn't have time to delve into details wants to know what to do.

How then does the CDC calibrate its guidelines? If it sets its standard too liberally, then those with medical conditions, persistent pandemic anxiety, and unvaccinated children panic at the masses of unmasked people milling about. But if it sets its standard too conservatively, then school education suffers, businesses struggle, and people complain about curtailed freedoms when they can't have their July 4 barbeque.

All this to say that taking into account the CDC's unenviable position and its bold stance, I am supportive of them. But I am also tailoring my personal decisions to my own risk calculation. Since I've worked in a hospital for over ten years, wearing a mask has minimal inconvenience; I simply don't mind. So I will likely continue to wear one even in settings where I don't have to. On the other hand, the CDC guidelines reassure me that I can attend a writing conference this summer set outdoors. I incorporate the CDC's guidelines with all the other data I'm weighing - my personal experience caring for COVID patients, my political and cultural milieu living in the Bay Area, my own anxieties and fears, my rational data-crunching mind, and my gut instinct. This is how we move forward with our lives.

I would be remiss to write about COVID in the intensive care unit without mentioning ECMO (extracorporeal membrane oxygenation) and lung transplant. These are extraordinary measures we might consider as a last-ditch effort in life-threatening COVID. They have been used successfully, but involve significant risk and potential harm to patients. I do not work in a center that provides ECMO or lung transplant, so we have to refer patients who may be candidates to other hospitals. I won't write a long blog because my experience is limited to the process of candidate selection and referral. But overall, I believe unfortunately, these are not miracle interventions that we can depend on. Resources and capacity are very limited, and although I have referred many patients for these possibilities, far more of our referral requests are declined than accepted. Realistically, we cannot count on them as a solution to life-threatening COVID.