Dear Dr. Eva,

From what I’ve read, none of the really dangerous new strains of Covid has made it to the United States.  Do we need to be concerned about the new strains at this point?


Dear Skeptic,

We should be concerned about mutant new strains of Covid. Many new strains are being found. Some are about as dangerous as the original virus, some are more contagious, and some are more deadly. The B.1.1.7 strain,  also called the UK or London or Kent strain, is now the dominant (main) strain of Covid in some states in the US, and it is spreading rapidly. The B.1.17 strain is much more contagious and also more deadly than the original strain.  Fortunately, the currently available vaccines provide protection against it.

The dangerous Brazilian or P.1 strain, which is causing a high rate of death in Brazil, also  appears to be prevented by currently available vaccines.  Although less than 1000 cases of the P.1 strain have been reported in the United States so far, it is expected to spread rapidly. This is because, like the B.1.1.7 strain, the P.1 strain is much more easily transmitted than the original strain of Covid. It will spread quickly within the population. A worrisome  aspect of the P.1  strain is that it can infect even people who have recently been ill with the original strain of Covid.  Any of the currently available vaccines is more effective in preventing Infection with new Covid strains than having had the disease.

Dr. Eva

Dear Dr. Eva,

What do you think about the new CDC guidelines that say it is now OK for Covid-vaccinated people to get together outdoors? Do you think it is safe? What about indoors?

Indoors Gal, Especially in summer

Dear Indoors Gal,

It’s a calculated risk, and everyone has to make their decisions based on their risk tolerance, their vulnerability to Covid, and the vulnerability of people they spend time with.     

There is a serious gap in the CDC recommendation: it talks about “small groups”  but doesn’t say what CDC considers a small group. My interpretation is that a small group means 10 or fewer people. Someone else’s interpretation might be that a large group is a full stadium, and a small group is a full movie theater.

It is safer for people who are less likely to become seriously ill from Covid to get together without masks than it is for people who have risk factors. Risk factors include older age, any chronic disease like kidney, lung, or heart disease, cancer, diabetes, and being overweight.

Some obvious questions are, how old is older? How much overweight is dangerous? In both cases, there is no cut-off line. With weight, the heavier you are, the greater your risk. Those with a BMI (body mass index) over 40 are at greatest risk. Risk also increases with each 10 years of age. People at greatest risk are those over 85. Among people over 85, 20% (one in five) of those who become infected with Covid will die of it.         

Most people don’t wear masks when they are with the people they live with.  Some people participate in “pods”, groups of a few friends or relatives who have agreed to always wear a mask except with members of their pod. These activities are even safer after vaccination.

Some general rules are:

  1. Wearing a mask is much safer than not wearing a mask.
  2. Outdoors is safer than indoors.
  3. Being vaccinated is much safer than not being vaccinated.
  4. The smaller group, the safer it is.
  5. Discussions about the how safe it is to meet without masks are only meant for people who have been fully vaccinated. It is never safe to spend time without a mask with someone who has not been fully vaccinated. Fully vaccinated means that you have received two shots of the Moderna or Pfizer vaccines, or one shot of the J&J vaccine, and it has been more than two weeks since you got the last shot.

Keep in mind that, even if you have no risk factors yourself, if you live with someone who does have risk factors, you should wear a mask to avoid bringing home one of the newer strains of virus that would be dangerous to them.


Dr. Eva

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Dr. Eva Hersh, MD
Dr. Eva Hersh, MD
Eva Hersh is a family physician. Send your comments and questions to her by email at