Considerations for Wearing Masks
- People age 2 and older should wear masks in public settings and when around people who don’t live in their household.
- Masks offer some protection to you and are also meant to protect those around you, in case you are unknowingly infected with the virus that causes COVID-19.
- A mask is NOT a substitute for social distancing. Masks should still be worn in addition to staying at least 6 feet apart.
- Wash your hands with soap and water for at least 20 seconds or use hand sanitizer with at least 60% alcohol after touching or removing your mask.
- Masks may not be necessary when you are outside by yourself away from others, or with other people who live in your household. However, some localities may have mask mandates while out in public and these mandates should always be followed.
- CDC is still studying the effectiveness of different types of masks and will update our recommendations as new scientific evidence becomes available.
Those classed as “clinically extremely vulnerable” may include the following (disease severity, history or treatment levels will also affect who is in this group):
- Solid organ transplant recipients
- People with cancer who are undergoing active chemotherapy
- People with lung cancer who are undergoing radical radiotherapy
- People with cancers of the blood or bone marrow such as leukemia, lymphoma or myeloma who are at any stage of treatment
- People having immunotherapy or other continuing antibody treatments for cancer
- People having other targeted cancer treatments which can affect the immune system, such as protein kinase inhibitors or PARP inhibitors
- People who have had bone marrow or stem cell transplants in the last 6 months, or who are still taking immunosuppression drugs
- People with severe respiratory conditions including all cystic fibrosis, severe asthma and severe chronic obstructive pulmonary
- People with rare diseases that significantly increase the risk of infections (such as severe combined immunodeficiency, homozygous sickle cell)
- People on immunosuppression therapies sufficient to significantly increase risk of infection
- Adults with Down’s syndrome
- Adults on dialysis or with chronic kidney disease (stage 5)
- Women who are pregnant with significant heart disease, congenital or acquired
Multi-layer cloth masks block release of exhaled respiratory particles into the environment, along with the microorganisms these particles carry.
Cloth masks not only effectively block most large droplets (i.e., 20-30 microns and larger) but they can also block the exhalation of fine droplets and particles (also often referred to as aerosols) smaller than 10 microns which increase in number with the volume of speech and specific types of phonation.
Multi-layer cloth masks can both block up to 50-70% of these fine droplets and particles and limit the forward spread of those that are not captured.
Upwards of 80% blockage has been achieved in human experiments that have measured blocking of all respiratory droplets, with cloth masks in some studies performing on par with surgical masks as barriers for source control.