Question: If a healthcare worker is treating a patient who isn't believed to have COVID-19, what type of PPE should they wear?

Answer passage (source: CDC):
page_title: Healthcare Infection Prevention and Control FAQs for COVID-19
section_headers: Given the potential for asymptomatic transmission of SARS-CoV-2, what personal protective equipment (PPE) should be worn by healthcare personnel (HCP) providing care to patients who are not suspected to have COVID-19?
section_content: The potential for asymptomatic SARS-CoV-2 transmission underscores the
importance of applying prevention practices to all patients, including social
distancing, hand hygiene, surface decontamination, and having patients wear a
cloth face covering or facemask (for source control) while in a healthcare
facility. To protect patients and co-workers, HCP should wear a facemask at
all times while they are in a healthcare facility (i.e., practice source
control). Use of a facemask, instead of a cloth face covering, is recommended
for HCP, because a facemask offers both source control and protection from
exposure to splashes and sprays of infectious material from others.

HCP caring for patients with suspected or confirmed COVID-19 should continue to wear gloves, a gown, respiratory protection that is at least as protective as a fit-tested NIOSH-certified disposable N95 filtering facepiece respirator (or facemask if respirators are not available), and eye protection (i.e., goggles or disposable face shield that covers the front and sides of the face).

HCP working in facilities located in areas with moderate to substantial community transmission are more likely to encounter asymptomatic patients with COVID-19. If COVID-19 is not suspected in a patient presenting for care (based on symptom and exposure history), HCP should follow Standard Precautions (and Transmission-Based Precautions if required based on the suspected diagnosis). They should also: 

Wear eye protection in addition to their facemask to ensure the eyes, nose, and mouth are all protected from splashes and sprays of infectious material from others.
Wear an N95 or higher-level respirator, instead of a facemask, for: 
Aerosol-generating procedures (See Which procedures are considered aerosol generating procedures in healthcare settings FAQ) and
Surgical procedures that might pose higher risk for transmission if the patient has COVID-19 (e.g., that generate potentially infectious aerosols or involving anatomic regions where viral loads might be higher, such as the nose and throat, oropharynx, respiratory tract) (see Surgical FAQ below).
Respirators with exhalation valves are not recommended for source control and should not be used during surgical procedures as unfiltered exhaled breath would compromise the sterile field



For HCP working in areas with minimal to no community transmission, the universal eye protection and respirator recommendations (described above) for areas with moderate to substantial community transmission are optional. However, HCP should continue to use eye protection or an N95 or higher-level respirator whenever recommended for patient care as a part of Standard or Transmission-Based Precautions. Universal use of a facemask for source control is recommended for HCP.


Depending on testing availability and how rapidly results are available,
facilities can also consider implementing pre-admission or pre-procedure
testing for COVID-19. Testing results might inform decisions for universal use
of eye protection and respirators as described above, especially if there are
PPE shortages. Limitations of using this testing strategy include obtaining
negative results in patients during their incubation period who later become
infectious and false negative test results, depending on the test method used.
Definitions:

Substantial community transmission: Large scale community transmission, including communal settings (e.g., schools, workplaces)
Minimal to moderate community transmission: Sustained transmission with high likelihood or confirmed exposure within communal settings and potential for rapid increase in cases
No to minimal community transmission: Evidence of isolated cases or limited community transmission, case investigations underway; no evidence of exposure in large communal setting


Reviewer feedback on this answer:
This answer provides comprehensive information on what PPE healthcare providers should be wearing when providing care to patients in different types of facilities.
This correctly gives explanation and preventive measures that should be taken by people who care for covid 19 patients.
This gives a great outline and clear examples of what to use to ensure safety

Reviewer ratings:
Excellent
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