When are the experts planning to get theirs?

The experts we interviewed almost unanimously encourage those 65 and older, as well as those of any age who are immunocompromised, to get an additional booster as soon as they’re eligible. Some also say that people between 50 and 65 who are generally healthy should consider doing so if they live or work around a lot of people, like in nursing homes or hospitals.

For those who don’t fall into one of those categories, but are eligible now — for instance, over 50 and in good health or with a mild underlying condition — the optimal timing is less clear. It depends on each person’s age, health, environment and behavior and appetite for risk.

Here is how six Bay Area health officials, infectious disease doctors and immunologists are approaching these questions in their own lives. Responses are edited for brevity and clarity.

Dr. Karen Relucio, public health officer for Napa County

Age 54, healthy, has asthma.

Q: Have you gotten a second booster?

A: Not yet. I plan to get it as soon as Friday comes around, when I can get into a Friday (vaccine) clinic. I’d rather not miss work if I have side effects.

Q: Would you recommend people 65 and older get one right away?

A: Yes. I’d recommend that for my parents.

Q: When is the best time to get it?

A: People are going to have to assess the risk. It’s hard to predict the surge. So if you’re going to wait until the next surge, you’re taking a chance. I was asked by someone who stays at home, doesn’t go out much, doesn’t eat at restaurants, but is traveling in July. If that person is not going to engage in anything that’s high-risk, they might want to delay it because they want to have the maximum protection during the time they’re traveling.

Q: What do you think about waiting for a “better” vaccine that may come out later?

A: There’s nothing imminent that’s coming out. People are waiting for a wider scope vaccine. We know it’s under development but we haven’t heard it’s going to be rolled out imminently.

Dr. Bela Matyas, public health officer for Solano County

Age 63, healthy.

Q: Have you gotten a second booster?

A: I’m not eligible yet. My third (shot) was less than four months ago.

Q: Do you plan to get one once you’re eligible?

A: I will probably monitor my risk scenario. If disease rates remain low and I’m not planning on doing anything particularly high risk, I’ll probably wait until fall.

Q: Who would you recommend get it as soon as they’re eligible?

A: Residents of long-term care facilities. The environment of a long-term care facility is high risk. And people with underlying immune-compromising conditions. I don’t not recommend it for everyone else, but I do also respect that individual circumstances vary.

If you’re boosted and the disease rates are low, you might want to wait until you’re going to encounter a scenario of higher risk like travel overseas, and get your booster before you travel. If you’re otherwise healthy and had your third (shot) and not planning on a high-risk activity, maybe you wait until winter and it’ll protect you to the next winter.

Dr. Sefanit Mekuria, deputy health officer for Contra Costa County

Age 36, healthy.

Q: Have you gotten a second booster?

A: I’m not eligible because I’m not over 50.

Q: Who would you recommend get it as soon as they’re eligible?

A: My parents have a lot of health conditions. So I’d recommend (people with) health conditions, or immune-compromised, much older…I definitely recommend my parents get a second booster. They’re very active in church and get a lot of visitors.

Q: How should people decide when is the best time to get it?

A: If they’re more vulnerable, have travel plans, more exposure due to work, or are immune-compromised, maybe getting a booster is higher on their list for now. And others can consider potentially waiting a little longer.

Q: Is there any potential downside to getting many shots in a short period of time?

A: I don’t know of any downside. There’s been no downside medically in doing that, historically. The first year of life, you get many shots. MMR (measles, mumps and rubella), Hepatitis B, pneumococcal, polio, rotavirus, DTaP (diphtheria, tetanus and pertussis). You get five, sometimes four doses a year. For example, with pneumococcal vaccine, within the first year of life, you get four doses of the same vaccine. And DTaP is the same way. The COVID-19 vaccines are very safe and effective. Of course, we’re still learning a lot about COVID and will learn more. In general, with vaccines, there’s no real downside.

Dr. Curtis Chan, deputy health officer for San Mateo County

Late 40s, healthy.

Q: Have you gotten a second booster?

A: I’m not eligible yet. I’ve suggested to my parents and in-laws, who are in their 70s and 80s, and relatively healthy, that they should get a second booster. But I have not made an appointment for them. The first vaccination series, I made appointments for all four of them. I think they’re still pretty well protected, but I’m encouraging them to get an appointment. I more urgently asked them to get their first booster. But I still think it’s a good idea to get their second booster if they plan to socialize indoors.

Q: Are there any potential downsides to getting many shots in a short period of time?

A: The results from Europe, including the Israeli studies, show that the fourth dose is safe. From a kind of biological plausibility perspective, it doesn’t seem like it would be harmful either, by the way the mRNA technology works. But we also want to be cautious, we don’t want to over-recommend vaccines either. The FDA and CDC have made the right move by saying this vaccine is safe and effective and it’s available. This vaccine seems to be safer than many other vaccines that have been utilized for decades. I’m a pediatrician who’s vaccinated many kids. This happens to be a remarkably safe vaccine.

Dr. John Swartzberg, professor emeritus of infectious diseases and vaccinology, UC Berkeley School of Public Health

Age 77, healthy.

Q: Have you gotten a second booster?

A: Yes (this week).

Q: What went into that decision?

A: A couple of events scheduled for later this month. One is a wedding reception that we really want to enjoy. The other is a party that friends are having. We thought, “Why not add the protection now. We’d still be protected for our granddaughter’s college graduation in May.”

My calculus was I really want to go to that graduation, and I haven’t seen my daughter and her family in months because they’re across the country. Given that’s going to increase my risk with travel and the graduation, I want to be protected. If I didn’t have the trip coming up, the way my wife and I live, our risk is quite low. I might’ve dragged my feet a little bit to see where things were going with the pandemic.

What about people 50 to 65? Should they be getting it? The risk is much smaller than if you’re over 65. But what are they doing, what is their work? My daughter-in-law is a physician (in her early 50s). She’s going to get (a second booster) because she works at a hospital so she wants to have that added protection. I think that makes sense.

Q: Is there any downside to getting a second booster?

A: I don’t know of any downside to getting this fourth (shot). People have raised the question of T cell exhaustion. We haven’t seen any evidence of that. I have not seen any data to suggest there’s a downside. I have seen data showing there’s an upside. It’s just a question of how long that upside is going to last.

Nadia Roan, immunologist and investigator at San Francisco’s Gladstone Institutes

Early 40s, healthy.

Q: Have you gotten your second booster?

A: No, because I am not eligible.

Q: Do you plan to get one if/when you become eligible?

A: I will likely get one if/when I become eligible, but I do not see a need to rush into it.

Q: Is there anyone you’d recommend get a second booster as soon as they can?

A: I suggest immunocompromised individuals get a second booster as soon as they can. For elderly individuals, I think it is a good idea to get a second booster when they can. It may not be necessary, but will decrease chances of a breakthrough infection.

Q: Is there anyone you’d recommend waiting?

A: No. But I also think it’s important to highlight that a second booster is not necessary to prevent severe disease in the vast majority of vaccinated individuals. So non-eligible people should not try to get a second booster early, it’s not needed.

Q: Is there any potential downside to getting many shots in such a short period of time? Does “T cell exhaustion” happen with COVID shots?

A: T and B cells can develop better memory when re-exposure to viral proteins is more spaced out. All currently eligible individuals would be getting their second shot at a time that is spaced out far out enough so that one doesn’t need to worry about the time period being “too short.”

T cell exhaustion is the process by which continuous encounter of T cells with the proteins they recognize will cause them to become “exhausted” and not respond as well. This is commonly seen in cancer, where cancer cells recognized by the T cells stay around and cause the T cells to become exhausted; and chronic viral infections like HIV, where T cells recognizing HIV become exhausted since the HIV is constantly there in the absence of treatment.

Importantly, there is no evidence that T cell exhaustion occurs during COVID vaccination or boosters. The protein that the COVID vaccines encode is made temporarily and then goes away. When a booster is given, the protein is temporarily there again and then goes away. This is in fact a classical way to make “good” (and non-exhausted) T cells.