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This is a bi-weekly Q and A column written by Dr. Lydia S. Segal in conjunction with Chaffee County Public Health. This column is focused on questions readers have about COVID-19 news and science.  As Segal points out, ‘Everything I write today is valid for today. COVID-19 news and science are rapidly evolving, assume updates will be made”

QUESTION: Are we at herd immunity yet?

ANSWER: Herd immunity is the term applied to a population when a high percentage of people have either had the disease or been immunized. This high level of immunity in a community by default protects those not vaccinated and reduces the likelihood of variants evolving. Although there is debate as to what percentage would bring forth general protection, the overall consensus is that it should be around  85 percent.

Lydia S, Segal, MD, MPH There is new data that shows that about 43 percent of the adult population in the country has had COVID and 65 percent have been fully vaccinated. Some people have, of course, been both vaccinated and had COVID.  Chaffee County summary data: All residents: 64 percent vaccinated, over 65-years-old: 89 percent vaccinated, all residents: boosted: 39 percent.

While these numbers provide some level of comfort in that a large percentage of the population has some level of immunity, no one really knows how long and how effective that immunity will be. Scientists are looking at all parts of the immune system to learn more about immunity duration and effectiveness.

And though everyone is tired of hearing this, it is really better to be vaccinated and not have gotten COVID, if for no other reason than to avoid the 10 to 20 percent risk of getting long COVID and the very real risk of experiencing a cardiovascular consequence such as a heart attack or stroke.

QUESTION:  There has been a lot of debate as to how SarsCoV2 came to be in humans. Is there any new information about the origins of the virus?

ANSWER: The origins of SarsCoV2 have been under debate since the pandemic started in the winter of 2020.  There are several new studies, done at academic centers and peer-reviewed, that strongly support the contention that the virus came from animals that were consumed from the Wuhan Market. This ‘spillover’ from animals to humans is common with other viruses, as well.

QUESTION:  What is happening with vaccines and children?

ANSWER: After initial clinical trials, more data in the real world is becoming available, for all age groups under 18 years of age. First, there is waning immunity for 5 to 11-year-olds after 28 days, regardless of variant. The good news for this age group is protection against severe cases requiring hospitalizations is still strong. This finding was substantiated in two separate studies released recently.

The 12 to 17-year-old age group seems to be better protected in terms of waning immunity and hospitalizations than the 5 to 11-year-olds. A second dose does make a difference.

The dosing for the 5 to 11-year-olds is one-third the dose of the over 12-year-olds which appears at this point to explain the difference in vaccine effectiveness.  Also, boosters make a difference in the amount and speed of waning immunity. The FDA approved boosters for 5 to 11-year-olds in October 2021. The recommendation is to vaccinate and booster 5 to 11-year-olds.

The clinical trials for the 2 to 5-year-olds are expected to be complete in the spring for review by the FDA.

QUESTION:  To mask or not to mask, that is the question readers ask.

ANSWER: There is so much new information about masking and social distancing, it is understandable to be confused. The CDC has an updated web page that shows by county the level of risk which determines masking guidelines. The lower the risk, the less masking and other mitigation measures are required/suggested. (

This risk rating system is based on the number of cases, number of COVID hospitalizations, and number of available hospital beds in the county. Currently, Chaffee County is rated ‘low’.

But what does this mean in real life? We can feel comfortable taking off our masks inside assuming we are vaccinated and under 65, healthy, and not in contact with those who might be at high risk. Masking continues to be required on public transportation and indoors in airports, train, and bus stations.

Individuals who are not vaccinated should mask and stay six feet away from others, especially those at higher risk.

But ultimately, each one of us has to make his or her own decision about what to do for ourselves and our family. A word of caution: the risk level could very well change. At the moment there is no known worrisome new variant but that does not mean it will stay that way. Scientists are constantly on the lookout for a new variant that may be more severe than what we have already experienced.

If you have questions you would like Dr. Segal to address in a future COVID Q and A column, please write to

For more information about COVID and vaccines, eligibility, and appointments, see the links below. Pharmacies and doctors’ offices are getting shipments of vaccines. Information will be posted in this news source and on the county public health and hospital web pages.

Pharmacies with vaccine clinics:

Salida:  Safeway, Walmart and Salida Pharmacy

Buena Vista: Mt Shavano (LaGree’s), City Market, BV Drug and Valley-Wide Health

By Lydia S. Segal, M.D., MPH