When my 88-year-old patient with diabetes and obstructive lung disease told me that he was planning to attend a family holiday get-together, I was surprised and dismayed.

His other family members had been in the same household “bubble” and felt safe around each other — but he lived elsewhere. They pleaded with him not to attend, but he insisted. When I expressed my concern, he replied with a sentiment I’ve been hearing often from my older patients.

“Doc, I don’t know how much longer I’ll be around. My family is important to me so I’ll just take my chances. We got together for a Halloween party and that went fine, so what’s one more visit going to do?”

While I certainly saw his point of view, I knew he was missing some very important parts of the equation. If you are taking proper COVID-19 precautions, the world can seem like a viral swarm that you just have to navigate without being “stung.” However, since COVID-19 often has no symptoms, it’s easy to forget that, although you feel great, you can actually be the “stinger.” In fact, the U.S. Centers for Disease Control and Prevention has estimated that nearly half of infections result from transmission from asymptomatic people.

“I’m glad luck was on your side at that party, but what if you pick up the virus before the next gathering and have no symptoms? Then you might infect your family members without realizing it,” I replied.

“Well,” he said, “I’ll just get tested a few days before I go.”

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Here was misunderstanding number two. It may take a few days after exposure and infection for your test to turn positive, and even longer for symptoms to develop, if you’re going to have them. A negative test before the event may provide false assurance.

Finally, I asked my patient the most difficult question.

“How does your family feel about the prospect of you becoming ill or dying from COVID?”

I knew he had come to terms with his own personal risk, and accepted the chance that he could become seriously ill or die if infected with the virus. But were his family and friends ready to risk losing him to a preventable infectious disease?

The conversation would be very different if he were refusing treatment for an advanced or end-stage disease such as cancer. The treatment might have risks or side effects that he would not want to be subjected to, and that is his prerogative. But if his own family unknowingly infects him with a virus and he suffers or dies from it, they may feel responsible, and be plagued with prolonged and agonizing guilt. I felt certain that the last thing my patient wanted was for his family to suffer.

He left the office still feeling unsure about what to do, but he thanked me for providing some food for thought.

If you are in a situation similar to my patient’s, consider the risk of COVID-19 transmission that you may unknowingly pose. Also, think of the impact that your preventable illness may have on those who are close to you. Further, we must all bear in mind our civil obligation to be responsible citizens, and do everything we can to prevent the spread of COVID-19, so that we don’t overwhelm our health system’s capacity to care for us.

Hospital beds are filling fast, and the health-care workforce is exhausted and stretched thin. If you took risks on Thanksgiving, best to lie low for at least a week or so and monitor yourself closely for fever, cough or other new symptoms; contact your primary-care provider right away if any should occur.

Oh, and by the way, remember to get a flu shot.

Jeffrey Millstein is a primary-care physician and medical director for patient experience, regional practices at Penn Medicine.