









































                                                                                                                         2021, Vol. 1 (S4) 9-10 
 https://doi.org/10.47488/dhrp.v1iS4.24 

  
 

http://dhrproceedings.org 9 © DHR Health Institute for Research and Development 
 

 

EDITORIAL 

Why Should Vaccinated People Wear Masks Indoors in Areas of High  
Community Transmission? 
Rationale for CDC’s Recent Recommendation

 
On April 27, 2021, the Centers for Disease Control 
& Prevention (CDC) recommended that individuals 
who are fully vaccinated do not have to wear their 
masks when outdoors unless they are in crowded 
gathering. As more data became available, on June 
15, 2021, the CDC updated their advisory further 
easing masking restrictions for vaccinated 
individuals. As part of this new advisory, masking 
was not required (both indoors and outdoors) for 
vaccinated individuals except for certain conditions 
in which it was mandatory for all irrespective of 
their vaccination status. The latter included the 
requirement to mask while using public transit; in 
healthcare facilities; correctional and detention 
facilities; homeless shelters; and in K-12 facilities. 
This latest CDC advisory was viewed as an 
affirmative consequence of vaccination placing 
greater burden on people to get vaccinated. 

The recent surge in infections with the SARS-CoV-
2 Delta (B.1.617.2) variant and the evolving public 
health crisis has prompted the CDC to reconsider 
and reverse its earlier advisory about masking for 
vaccinated individuals (1). The interim 
recommendations issued on July 27, 2021, stated 
that fully vaccinated people wear a mask in public 
indoor settings in areas of substantial or high 
transmission which includes all counties in the 
Greater Rio Grande Valley (2). It was also 
recommended that fully vaccinated people might 
choose to wear a mask regardless of the level of 
transmission, particularly if they are 
immunocompromised or at increased risk for severe 
disease from COVID-19, or if they have someone 
in their household who is immunocompromised, at 
increased risk of severe disease or not fully 
vaccinated. Lastly, it was recommended that fully 
vaccinated people who have a known exposure to 
someone with suspected or confirmed COVID-19 
be tested 3-5 days after exposure, and to wear a 

mask in public indoor settings for 14 days or until 
they receive a negative test result. 

It is notable that the majority of those recently 
diagnosed with COVID-19 fall in two distinct 
categories; unvaccinated and those who are 
vaccinated but have complicating risk factors (such 
as old age, diabetes, obesity, hypertension, 
immunosuppressed, etc.). The population most 
seriously affected are those who are unvaccinated. 
Given its high transmissibility and infectivity, the 
Delta variant is indifferent to the age of the patient 
as many newly diagnosed cases are in younger age 
groups including children. More importantly, 
majority of patients who are hospitalized with 
severe COVID-19 disease are those who are 
unvaccinated. On the contrary, vaccinated patients 
tend to develop mild SARS-CoV-2 infection which 
rarely requires hospitalization. In fact, most recent 
CDC data suggests that if infected, 99.99% of 
vaccinated individuals do not require 
hospitalization. 

This latest CDC advisory has understandably 
created some confusion among vaccinated 
individuals and has given voice to those who 
oppose vaccination arguing untenably that COVID-
19 vaccination is not protective against SARS-
CoV-2 infection. However, there is a reasonable 
scientific rationale for this advisory as various 
vaccines work differently in providing protection 
against the disease. For example, after vaccination 
against measles and mumps, a person is granted 
immunity for life. On the contrary, in the case of 
Influenza virus that causes seasonal flu, vaccination 
must be repeated year after year. Interestingly, even 
after vaccination against flu, people develop mild 
disease which rarely progresses to a state that 
necessitates hospitalization. The reason for this 
“breakthrough” infection is the inherent ability of 
the infecting agent (in this case the Influenza virus) 



DHRP, 2021, Vol. 1 (S4) 1-3  Editorial 

  
 

http://dhrproceedings.org 10 © DHR Health Institute for Research and Development 
    
 

to mutate and escape the vaccinated individual’s 
immune response. This is precisely what is being 
encountered in vaccinated individuals infected with 
the Delta variant. The 13-17 mutations endow the 
Delta variant with the ability to enhance its 
transmissibility and infectivity and to delude the 
immune system thus resulting in infection. Like 
many other vaccines, COVID-19 vaccination also 
does not prevent the individual from getting 
infected, but it will most certainly prevent the 
development of serious disease that may require 
hospitalization. Therefore, it is important for both 
vaccinated and unvaccinated individuals to wear 
mask as recommended by the CDC and for those 
who are unvaccinated…get vaccinated (if you 
qualify) as soon as possible…it may save your life! 

References  

1.  Interim public health recommendations for fully vaccinated 
people.https://www.cdc.gov/coronavirus/2019-
ncov/vaccines/fully-vaccinated-guidance.html. (Accessed on 
August 01, 2021, at 4:20 p.m., Central Standard Time) 

2. COVID-19 integrated county view. https://covid.cdc.gov/covid-
data-tracker/#county-view (Accessed on August 01, 2021, at 
4:32 p.m., Central Standard Time) 

Sohail Rao, MD, MA, DPhil 

Executive Vice President, DHR Health, 5501 S. McColl 
Road, Edinburg, Texas 

President & Chief Executive Officer, DHR Health 
Institute for Research & Development, 5323 S. McColl 
Road, Edinburg, Texas 

Corresponding author email: s.rao@dhr-rgv.com  

Disclosures: None 

ORCID: Sohail Rao: https://orcid.org/0000-0001-5027-
9992 

Manish Singh, MD, FACS 

Chief Executive Officer, DHR Health, 5501 S. McColl 
Road, Edinburg, Texas 

Disclosures: None 

ORCID: Manish Singh: https://orcid.org/0000-0003-
4146-3282  

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 
 

mailto:s.rao@dhr-rgv.com
https://orcid.org/0000-0001-5027-9992
https://orcid.org/0000-0001-5027-9992
https://orcid.org/0000-0003-4146-3282
https://orcid.org/0000-0003-4146-3282

