FILE - In this Sept. 14, 2021, file photo, a health worker administers a dose of a Pfizer COVID-19 vaccine during a vaccination clinic at the Reading Area Community College in Reading, Pa. A key government advisory panel overwhelmingly rejected Biden's plan to give COVID-19 booster shots across the board and instead recommended the extra vaccine dose only for those who are 65 or older or run a high risk of severe disease. (AP Photo/Matt Rourke, File)

Q: Two weeks ago, my friend got COVID a week before she was scheduled for her second booster. She is 55. She feels the second booster isn’t necessary now because she is effectively immunized. I understand that the second booster is recommended three to four months after recovery. Can you enlighten me? A mutual friend who is immunocompromised feels unsafe around her unless she is “fully boosted.” I feel stuck between two good friends.

A: Very recent evidence has shown that people who have had three doses of the vaccine do not receive a large boost in immunity from getting COVID at the time of this writing, when the omicron variant is dominant in North America. Your friend who had COVID has about the same risk of getting COVID again as she did two weeks ago. She still is highly protected against serious disease (causing hospitalization) and from death after three doses of the vaccine (compared with an unvaccinated person, or even a person who had only two doses), but she can certainly catch another case of COVID. A second booster shot (four doses total) appears to reduce the risk of infection by half and the risk of severe infection by about 80 percent, so at this time, I would still recommend a fourth dose to a person like your friend who got COVID. Waiting three months after infection is reasonable, but she also could get the vaccine earlier, once she has recovered from COVID.

Unfortunately, no combination of vaccines and infection is 100 percent effective at preventing another case, so people who are immunocompromised need to remain very vigilant. People at higher risk — like your immunocompromised friend — should ask about treatment options if they test positive for COVID. Many people get positive home-test results and don’t let their doctor know in time to get treatment early, when it’s most effective.

Finally, your mutual friend with the compromised immune system should consider Evusheld, an injection that provides good protection for six months.

Q: I’m a 63-year-old male who does weight-bearing exercises three or four times a week. I also am on multiple blood pressure meds, including atenolol, which slows the heart rate. What is the target heart rate while on this drug, for maximum cardiac health? .

A: There are two ways to answer your question, the difference being the target resting heart rate and the target exercise heart rate.

The goal for atenolol as a blood pressure medicine is not the resting heart rate but the resting blood pressure. However, atenolol and other beta blockers are seldom used as the first medicine to treat blood pressure, except in cases where beta blockers also are useful for something else.

Still, when a person requires multiple medications, beta blockers are often used as a second- or third-line treatment. If a person has good control of their blood pressure at a heart rate of 80, the medication is successful. However, most times, the resting heart rate needs to be in the 50s or 60s for the blood pressure to come down to goal in a patient taking a beta blocker.

The target exercise heart rate is usually recommended to be between 55 percent and 85 percent of your maximum heart rate, which can be measured by a stress test, or estimated by a calculator. Unfortunately, the calculator is only a rough guide at best, especially in women and in middle-aged (or older) people, and beta blockers have variable effects on individuals.

Q: I’m a 65-year-old female, nonsmoker, with very dry eyes living in a dry climate. My eyes often burn and tear up, which I find curious, having been diagnosed with dry eyes.

During the day, I use preservative-free eye drops and also place a warm washcloth over my eyes. Before bedtime, I apply an ointment or a preservative-free gel (which appears to be the most successful). However, all of the above provide only temporary relief.

My eye doctor has talked to me about punctal plugs that would initially be prior to a permanent solution (they dissolve over time or can be removed). What are your thoughts about these procedures? Would the punctal plugs be tight and uncomfortable? I don’t know anybody who’s had this done and have not been able to find much about success rates.

A: Dry eyes are a very common condition, especially in people living in dry climates. I suspect you may have the most common type, which I’ll discuss here.

Your eyes have three different types of fluids. The first is a long-lasting, oily type, secreted by the meibomian glands around the edges of the eyelids near the eyelashes. The second is a watery type, secreted by the large lacrimal glands in each eye near the temple. The third is made from mucus and produced by the lining of the eye, the conjunctiva. Excess watery fluid in the eye drains through the tear duct into the nose.

The warm washcloth your eye doctor recommended helps to open up the meibomian glands, which frequently get clogged up. Without the oily fluid, the tears quickly evaporate in the dry environment, leading to eye irritation and burning. This paradoxically causes more watery fluid from the lacrimal glands that causes tearing, which explains the curious symptom of watery eyes due to dry eye syndrome. There are several devices to treat blocked meibomian glands.

Artificial tears, gels and ointments are all reasonable first-line treatments. Punctal plugs reduce the loss of eye moisture through the tear ducts. I have had many patients treated with these, and most people do very well with them. I haven’t had people complain about any tightness or discomfort associated with the plugs, but many of my patients have had the plugs fall out, often due to rubbing of the eyes. Temporary plugs predict the success of a more permanent plug placed by the ophthalmologist for those who do well.

Q: Can those with gout safely take glucosamine/chondroitin supplements?

A: Gout is a metabolic disease of excess uric acid. It is characterized by crystals that are deposited into body tissues, such as in joints, kidneys and skin. Glucosamine and chondroitin are common supplements taken by people with osteoarthritis. There is not strong evidence that it helps any more than a placebo pill. Fortunately, there is no indication that either glucosamine or chondroitin increases risk for gout, and there is preliminary evidence that chondroitin may help prevent gout.

A patient with many years of gout can be predisposed to permanent joint damage, so managing gout well and early on helps to prevent arthritis.

Dr. Roach regrets that he is unable to answer individual letters, but will incorporate them in the column whenever possible. Readers may email questions to ToYourGoodHealth@med.cornell.edu or send mail to 628 Virginia Drive, Orlando, FL 32803.

“It’s serious,” Payne said Saturday afternoon. "People are dying. People have died. We just want ... the environmental injustice to stop in our community."