Should You Wear Your Mask Again as Delta Variant Surges?

Just as you thought we were in the home stretch of the COVID-19 pandemic, two new variants have emerged in the U.S., causing infection rates to rise, hospital beds to fill and regulators to recommend masks again.

Should you get out your mask? The U.S. Centers for Disease Control and Prevention is now recommending that even if you’re fully vaccinated you should wear a mask while indoors if you’re living in an area of high or substantial transmission. Around 46 percent of American counties have high transmission rates and 17 percent have substantial transmission rates. The CDC is also recommending that masks be worn by teachers and students while in school – regardless of vaccination status. 

A few months ago, the CDC relaxed the mask mandates for fully vaccinated Americans as vaccination rates surged. But two things have happened since they CDC last visited mask recommendations: The rate of Americans getting vaccinated slowed and two new variants emerged that are causing a new surge in infections. Now the dominant strain in the U.S., the highly contagious Delta variant (B.1.617.2) is now the dominant strain in the U.S., accounting for more than 80 percent of infections. 

The strain was first detected months ago in India and quickly became the dominant strain of India and Great Britain. It has mutations on the spike protein that can weaken the effectiveness of COVID vaccines by as much as 70 percent and enable the virus to pass antibodies naturally produced by a previous COVID-19 infection. This makes the variant more transmissible and can cause more breakthrough infections. In fact, scientists have found that vaccinated and unvaccinated people who have become sick with the Delta variant have similar viral loads and can spread the virus equally. 

The vaccines are still very effective at preventing severe illness against all the current variants. Breakthrough infections only account for a small percentage of hospitalizations; unvaccinated patients account for 97 percent of hospitalizations.

Delta isn’t the only concern on the CDC’s radar. Another variant, Epsilon (B.1.429), originated in Southern California and, like Delta, has more spike mutations and is more transmissible. 
   
Masks help reduce transmissibility but aren’t perfect. In addition to the general guidance for schools and vaccinated adults, the CDC also updated guidance for people with compromised immune systems and changed recommendations for testing of people who are vaccinated but have been exposed. The CDC recommends that fully vaccinated people might want to mask regardless of the level of transmission, particularly if they or someone in their household is immunocompromised or at increased risk for severe disease. A fully vaccinated person is exposed to COVID should be tested three to five days after exposure and wear a mask in public indoor settings for 14 days or until they receive a negative test.

The CDC did not change the recommendations for unvaccinated people; the agency still recommends that unvaccinated people wear masks and practice social distancing. Read all the guidelines here.