In an announcement on Tuesday, the Centers for Disease Control and Prevention recommended that fully vaccinated people living in areas of “high transmission” of the COVID-19 virus wear masks when indoors.
The recommendation, which is an about face from the guidance issued in May, is aimed at those who have not been vaccinated as well as those who have gotten the shots.
CDC Director Dr. Rochelle Walensky attributed the new guidelines to emerging information about the Delta variant of the novel coronavirus. According to Walensky, research is showing that “some vaccinated people infected with the delta variant after vaccination may be contagious and spread the virus to others,” she said at a press conference.
Fully vaccinated people with breakthrough infections caused by the delta variant carry an amount of the virus similar to the level of infection in unvaccinated people, Walensky said. That means a fully vaccinated person could easily infect someone.
The delta variant is more than two times as transmissible as the original strain of the COVID-19 infection.
Currently, the delta variant is responsible for more than 80% of new infections in the U.S.
Here is what we know about community transmissibility and the new guidelines:
What is community transmissibility?
Community transmissibility, or at what level a virus is spreading in the community, is calculated in two ways. First, community health officials look at how many new cases per 100,000 happen in a community in a seven-day period. Then they look at the percentage of positive diagnostic and screening tests in the last seven days.
What is high transmissibility?
When there are 100 or more new cases per 100,000 people in a community within the past seven days, and there is a 10% or higher increase in positive tests, the transmissibility rate in that community is considered high.
Is your community considered one of high transmissibility?
According to the CDC during the past seven days, 46.43% of the counties in the United States fall under the classification of high transmissibility.
According to the guidelines, masks are recommended for indoor public places in parts of the U.S. with at least 50 new cases per 100,000 people in the last week – a classification that sits below “high” and is called “substantial.”
For the past week, the counties that fall into the high and substantial categories would include 60% of U.S. counties.
Southern and Southwestern states are particularly hard hit now with every county in Arkansas, Louisiana and Florida having a high transmission rate classification, according to a CDC tracker.
States with a “substantial” rate of transmission include California, Oregon, Washington, Colorado, New Mexico and Illinois.
Fourteen states have a “moderate” rate of transmission that requires no indoor masking. There are no states that are considered to have a “low” rate of transmission.
How can I find out what my county is rated?
You can click here to go to an interactive map where you can find the status of your county.