Some people are concerned about taking the new vaccine. Should you get it now, wait, or take a pass? As a physician in the Bay Area, I jumped at the chance to get vaccinated out of fear of bringing the virus home to my family or infecting my patients. But others are afraid or hesitant; we tend to make personal health care decisions based on our information sources, our perceptions of risks and benefits, our mindset, and stories we hear from people we know.

Right now, we have a high risk of getting Covid-19. In Marin, there have been 9,329 cases as of Jan. 17 and 126 deaths, and these numbers do not include cases at San Quentin. Sixty percent of countywide deaths were in people age 80 and over, meaning 40 percent have been in those under 80. In Dillon Beach, Inverness, Point Reyes Station and Tomales, there have been 69 cases. Some of us have risk factors that make hospitalization or death more likely, but other seemingly healthy people die from the virus. And then there are new strains emerging, some more contagious.

Though the risk from the new vaccines is very low, we make decisions based on more than just facts. For some, hesitation over getting vaccinated can come from inertia, comfort with the status quo, or the attitude of “better the devil you know than the devil you don’t.” For those people, the fear of potential risk is strong. Reluctance can also be related to cultural values or a distrust of medicine. People respond to facts and choices in different ways, but a decision to delay has a cost, too, and now is a time to think through this discomfort.

What are the known potential risks of the vaccines? The side effects are similar to those of other vaccines—injection site soreness, fatigue or headache. Rarely, some individuals have allergic reactions. For this reason, before any vaccine, questions about prior allergic reactions to injections are important, as is waiting in the area for 15 minutes after the injection. Even people with severe food or other types of allergies are advised to get the vaccine after talking with their doctor. This is a balance of risk and benefit. 

The Pfizer and Moderna vaccines do not contain any virus or virus parts, and they cannot give you Covid-19. They use a technique that injects tiny pieces of messenger RNA. This mRNA carries the code to allow your cells to make the spike protein that covers the outside of the Covid-19 virus. The mRNA is held in fatty bubbles that help it enter your cells, which is necessary for your body to make the spike protein, but it can’t enter the nucleus of the cell, so it cannot change your DNA. Your body will then make some spike proteins, and then antibodies to the spike protein. 

This primes your body to respond should you encounter the real Covid-19 virus: Your body will already know how to make the antibodies to the spike proteins on the surface of the virus, even though it has never seen the whole virus before. mRNA breaks down rapidly, one of the reasons the vaccines have to be kept at such low temperatures and used rapidly when thawed.

Protection from the vaccines is not 100 percent, but individuals in the trials who did get Covid after the vaccine had milder disease. It is also possible that the vaccines’ protection may not be long lasting, as can be true of other vaccines. We do not yet have long-term data.

The Food and Drug Administration’s emergency use authorization was not just a political decision; an outside panel reviewed data from the vaccine trials and recommended it, and the F.D.A. approved use based on the benefits at this time outweighing the risks. Available data show the vaccines provide more than 90 percent protection about two weeks after the second dose. There are also other vaccines in development.

I think about a patient I was taking care of early in the pandemic, hospitalized with a fracture, who told me she did not believe in the virus. “Show me the bodies—I don’t see any bodies stacked up,” she said. Not everyone is open to a discussion of risks and benefits, so I told her about my colleague who was sickened with Covid, spent two weeks on a ventilator, and survived. It may not have changed her beliefs, but his story reminded me that severe infection can happen to the healthy, and I hope it personalized the risks a little for my non-believer patient. 

Whom do you trust for your health information? I encourage you to look at some of the U.C.S.F. physicians who are good communicators, like Dr. Bob Wachter and Dr. Peter Chin-Hong,  frequent commentators on television and Twitter. Dr. Paul Offit was on the F.D.A. advisory panel and is a national vaccine expert. Talk to your doctor. And if you have any family members old enough to remember polio, ask what those times were like for them.  The Marin County public health website will keep you up to date, at 

I strongly urge you to get the Covid-19 vaccine as soon as it is available to you, to protect yourself, your family, your friends and your community.


Dr. Martha Singer is an orthopaedic surgeon with interests in disability and medical ethics. She practices in the East Bay and lives part time in Inverness Park.