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Coronavirus variants explained: Conversation with John Haran

What are the practical implications of the new strains of the coronavirus that causes COVID-19? What advice do people need?

, MD, PhD, associate professor of emergency medicine and microbiology & physiological systems and clinical director of the , spoke with UMassMed News about research into coronavirus mutations, what is known about vaccines鈥 ability to fend off the new strains and the implications for what we can all do to stay healthy.

What do we know about the coronavirus mutations and how prevalent they are in the community?
鈥淭hese variants are the natural evolution of viruses, and not just viruses, but life. Bacteria do this on a slower scale and humans do it on a much slower scale. What viruses do is they introduce mutations into their genome pretty quickly when replicating, changing the virus鈥檚 structure a little, and those mutations that confer a benefit to the virus can grow and become a predominant strain. We鈥檙e learning about this daily now.

鈥淪o, the B.1.1.7 strain out of England was one of the first to gain world notoriety because it quickly overtook the country and soon became the predominant strain. This caused concern as it spread across the world. A South African strain (B.1.351), one from Brazil and another in California are spreading now too.鈥

What is the impact of the new variants?
鈥淭he B.1.1.7 strain had mutations that made it easier to make copies of itself. It is causing a lot higher number of viral particles in the upper respiratory tract. And that gives it an advantage because when somebody sneezes or when there are droplets, there is more virus per droplet than there would be in the original strain. And so it becomes much more highly contagious.

鈥淭his new strain is not causing more severe infections. That鈥檚 because it is not changing how it makes you sick; it鈥檚 just changing how much is being produced in the upper respiratory tract.鈥

鈥淏ut the biggest problem is when you increase the number of people being affected, you鈥檙e increasing the number of people that then have complications from getting sick from the disease.鈥

Do the current mRNA vaccines appear to protect against known variants?
鈥淎s far as we know right now, we believe that the vaccine is still effective because of where the mutations occur.

鈥淧fizer put out recently a non-peer-reviewed paper in which they took the serum from people that had gotten the vaccine and mixed it with this new strain. But it was a very small study.

鈥淢oderna said that studies from people vaccinated with its vaccine showed they appeared to be protected against key emerging variants, including the English and South African ones. It is studying whether a booster dose will further increase effectiveness against new strains.

鈥淵es, another booster may be needed, and this research is not peer reviewed, so there are still big unknowns. And while still effective, the vaccines have been reported a little less effective on the South African strain. What we know changes daily.鈥

Are the current guidelines about mask wearing and social distancing still what people should follow?
鈥淭hose policies don鈥檛 need to be changed; they need to be adhered to. It is more important than ever. The problem with the pandemic is as it keeps going on, people get tired of wearing a mask, social distancing and not gathering in groups, so they let their guard down. And that is fuel for the fire for these new strains.鈥

What about being less at risk when you鈥檙e outdoors?
鈥淏eing outside is just a proxy measure for social distancing. If you鈥檙e outside and you鈥檙e doing things you鈥檙e usually farther apart. Air circulation can also be thought to be part of that. But cold or heat having an impact鈥攖hose are old wives鈥 tales as far as affecting how viruses spread.鈥

Are people who previously had COVID-19 getting reinfected with the variant strains?
鈥淵es they are, but we don鈥檛 know to what extent they are. There鈥檚 a little bit of questioning, when someone returns with a second infection, whether it is the same, prolonged infection, or something new.

鈥淲e鈥檙e studying at UMass Medical School now, and it鈥檚 being studied worldwide, if you get the vaccine, do you build enough immune response to it? And then does the immune response protect you from different strains that are circulating? Those are all big, big questions we don鈥檛 have all the answers to.鈥

What else should people know about coronavirus variants?
鈥淕etting answers to these questions, in the previous world we lived in, took years of research and we鈥檙e trying to fast track all of this. So sometimes we think we know the right answer and it changes pretty quickly when we get more evidence.

鈥淭hat鈥檚 why the CDC has recommended that even if you鈥檝e had an infection, you get vaccinated.

鈥淲e鈥檙e not going to pass through the winter and then all of a sudden go back to life being how it was prepandemic. This is something that is probably going to be with us for years. So, making it part of your daily life is something that would help, especially with things like wearing a mask when going out in public and good hand hygiene.鈥