This material is designed to help you talk to your patients and help them understand the benefits of vaccines. Find printable infographics and helpful videos for your patients on TMA’s Talk to Your Patients webpage and through Vaccines Defend What Matters, the Texas Medical Association’s integrated, multimedia public health education and advocacy effort..
By Sean Price
Alpha. Delta. Epsilon. Omicron. These and other variants of COVID-19 have made their way through the U.S. and Texas, and new ones will almost certainly be coming along.
Over seven weeks in May and June 2021, the highly transmissible delta variant shoved aside the original SARS-CoV-2 virus and any other variations circulating at the time to become the dominant COVID-19 variant in the U.S, according to the Centers for Disease Control and Prevention. Then in December, the still more transmissible omicron variant pushed aside delta to become dominant in about three weeks.
Variants are caused by slight mutations in the original virus, explains Roy F. Chemaly, MD, chief infection control officer and director of clinical virology research at The University of Texas MD Anderson Cancer Center in Houston. The mutations are not drastic enough to create a genetically new virus, but they are significant enough to change the way the virus behaves, making it more or less transmissible or virulent, for instance.
The changes found in each new variant pose two potential problems in fighting the disease, Dr. Chemaly says.
“First, the vaccine could be less effective, and with omicron it probably is,” he said. “Also, the treatment [for COVID-19], the monoclonal antibodies, may not be as effective.”
At the same time, however, the mutations that lead to variants can occur only if there are enough unvaccinated people around to be infected, Dr. Chemaly says.
Right now, Texas’ COVID-19 vaccination rate is 61%, according to the Texas Department of State Health Services. That leaves 39% of the population vulnerable to COVID-19 and, in turn, heightens the risk that vaccinated people will get breakthrough infections.
“If we don’t stop [COVID-19] with herd immunity, with enough people vaccinated, it’s going to keep circulating at high levels,” Dr. Chemaly said. “In some hotspot areas, you may see new variants.”
What is a variant?
Like many diseases, COVID-19 is caused by a virus. As viruses circulate among people, they rapidly go through changes, or mutations. The mutations usually are not big enough to create an entirely new disease, but they are big enough to change the way the virus behaves in people, creating a variant. For instance, a mutation may cause the virus to spread more slowly or faster. Or, it could make the virus more or less deadly. This can happen with any disease spread either by a virus, like COVID-19, or by bacteria, like whooping cough or tuberculosis.
How many COVID-19 variants are there?
There have been several, but so far only two have had a big impact. The delta variant, which became the dominant type of COVID-19 in summer of 2021, spread faster and was more deadly than the original COVID-19 virus. In December 2021, the omicron variant became the dominant type of COVID-19 because its mutations caused it to spread even faster than the delta variant. Fortunately, for most people, omicron appears to be less severe than the delta variant. But the fact that it spreads faster means it will affect and possibly harm a larger slice of the world’s population.
What problems do COVID-19 variants create?
Variants are caused by gradual changes over time. Those mutations may make some COVID-19 vaccines less effective against a new variant. That appears to have happened with omicron. Variants also can make treatments like monoclonal antibodies – which boost a person’s immune system’s ability to fight disease – less effective. That means many people who are infected with the omicron variant have a greater risk of hospitalization, long-term illness, or death.
How do we fight variants?
Vaccination against COVID-19 is the best weapon against variants. Variants can occur only when the virus is free to spread and mutate. Vaccines give people a high degree of immunity to the disease. That creates a barrier that makes it harder or impossible for the virus to spread. Other precautions, like masking and physical distancing, also keep the disease at bay. If enough people use vaccines, masking, and physical distancing, COVID-19 variants will have no way to spread.
Sources: Roy F. Chemaly, MD; Centers for Disease Control and Prevention