A healthy living blog from Marshfield Clinic Health System

4 things to know about COVID-19 delta variant and other COVID variants

The SARS CoV-2 virus continues to naturally mutate into different strains of COVID-19. The delta variant was first detected in the U.S. in March 2021. This variant accounts for a recent growing number of new COVID-19 cases across the states, including Wisconsin.

It’s important to be fully vaccinated to protect yourself from the COVID-19 variants.

“The biggest issues with delta variant is that it spreads more easily than before,” said Kate Maguire, Infection Prevention director at Marshfield Clinic Health System. “With the original virus in the U.S., we would expect one person to potentially infect three people. However, according to BBC News article, alpha variant infects about four to five and delta is now five to eight or so.”

Virus variants spread more quickly and easily

Scientists continue to monitor changes in COVID-19 variants and spikes in virus cases. Research is conducted to understand how variant changes affect how the virus spreads and how sick people will get from it. Centers for Disease Control and Prevention (CDC) continues to monitor and research COVID-19 and vaccine effectiveness. Guidelines for fully vaccinated individuals was updated based on that research.

COVID-19 vaccines are effective against the delta variant

Data shows that the COVID-19 vaccines are extremely effective in protecting fully vaccinated people from catching and spreading the virus, including the delta variant. However, it is critical that you are fully vaccinated to be protected.

Dr. Rochelle Walensky, CDC director, stated in a telebriefing July 27, 2021, that research shows “individuals who are fully vaccinated may still be contagious” if infected by the delta variant. Walensky said the risk of a symptomatic infection is reduced sevenfold for fully vaccinated people, and the risk of hospitalization is reduced twentyfold.

Masking recommended to protect yourself and others

In areas with substantial and high transmission, CDC recommends fully vaccinated individuals wear masks in public indoor settings, including schools, to help prevent the spread of the delta variant and protect others. The CDC defines high transmission as 50 cases or more per 100,000 people over the past seven days.

“A large portion of the world remains unvaccinated,” Maguire said. “It’s important to wear a mask in public if you are not vaccinated to prevent the delta variant from becoming a dominant strain. We are seeing areas where delta variant is strong due to the lack of vaccination, masking and social distancing.”

Delta variant can lead to hospitalization and death

People infected with the delta variant are more likely to need hospitalization than those infected with earlier strains of the virus.

As of July 17, 2021, the delta variant accounts for more than 83% of new COVID-19 cases.

“We are getting there, but we want everyone in our communities to be safe and healthy,” Maguire said. “Let’s put an end to these virus variants to have a safe and healthier community, one vaccine at a time.”

Talk your provider about the COVID-19 vaccine. For common questions about the COVID-19 vaccine, visit our COVID-19 FAQ page.

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  1. Aug 27, 2021
    • Aug 27, 2021

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