The Delta Variant is 40% More Infectious than the Original COVID-19 Strain

This article was contributed by West Virginia Coronavirus Czar Dr. Clay Marsh and Major General (Ret.) James Hoyer and focuses on the Delta Variant and how to combat it in West Virginia.

The COVID-19 pandemic has decreased markedly in numbers of new cases, hospitalizations and deaths in West Virginia and in the United States. This is good news.

However, when carefully looking at the data, it is evident that the impact of reduced COVID-19 infections, hospitalizations and deaths are largely in our residents who are not vaccinated. In fact, the state of Maryland reported on July 7th that every citizen who died of COVID-19 in June was unvaccinated. Vaccination protects us against dying of COVID-19 in West Virginia and across the world.

In real world use against the COVID-19 Delta variant (first described as the Indian B.1.617.2 variant), being fully vaccinated with Pfizer and Moderna vaccines (14 days after the second dose) reduces the risk of contracting COVID-19 by 64-88% and protects fully vaccinated people against severe disease, hospitalization and death by 94%.
 
Countries that vaccinated their population with a single dose of Pfizer or AstraZeneca (primarily the United Kingdom) or those unvaccinated saw a rash of new infections from the Delta variant and saw more hospitalizations. In the United Kingdom, the Delta variant has replaced the Alpha (previously known as the United Kingdom variant, B.1.1.7) as the cause of new cases of COVID-19, demonstrating its superior transmission. The Delta variant is now the predominant form of COVID-19 seen around the world and is the most infectious form of COVID-19 in the U.S.
 
In the U.S., new cases of COVID-19 caused by the Delta variant are growing explosively. This variant is at least 40% more infectious than the Alpha form, which is currently the predominant form of the virus in West Virginia and the U.S.
 
Infectious diseases experts use the R₀ value (pronounced “R naught”), a mathematical term that indicates how contagious an infectious disease and how quickly it reproduces when transmitted to new people. The R₀ value shows how many people are likely to be infected when exposed to a person infected with COVID-19, and the data are concerning. While the initial COVID-19 virus has an R₀ of 2.3-2.7 (one infected person is likely to infect 2.3 to 2.7 unaware people), the Alpha (United Kingdom variant) has an R₀ of 4-5, and the Delta (Indian) variant has an R₀ of 5-8.
 
This is an extraordinary rise in infectivity and should give all unvaccinated or partially vaccinated West Virginia residents urgency to be fully vaccinated.
 
The bottom line from this new data?
 
Unvaccinated citizens are the ones that are being infected and dying of the new Delta variant of COVID-19. Partially vaccinated West Virginia residents are also at risk of more severe disease manifestations and breakthrough infection.
 
We can’t afford to be complacent. Full vaccination is protective. 

In countries with poor access to vaccines, COVID-19 will continue to mutate (remember, it can only mutate when it infects humans), and new variants will follow. The more completely our state’s residents become vaccinated, the stronger firewall we build against the virus infecting West Virginians, spreading in West Virginia and mutating in West Virginia.

As of this writing, 53% of our vaccine eligible population is fully vaccinated and 65% has one shot. That is very good and needs to continue to climb up, as 87% of our population over age 65 has one shot and 79% of our population over age 50 has one shot.

The remainder of our vaccine eligible population needs to continue to choose vaccination.
 
Let’s go West Virginia. Shine the light. Choose vaccination. 
 
It is the path to a healthy, safe and bright future for all.