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Responding to SARS-CoV-2 Infections in Acute Care Facilities

Responding to SARS-CoV-2 Infections in Acute Care Facilities

Considerations for the Public Health Response to SARS-CoV-2 in Acute Care Facilities

Updated Dec. 28, 2020

Background

A new instance of SARS-CoV-2 infection in a healthcare provider who interacts with other healthcare personnel (HCP) or patients, or in a patient not in Transmission-Based Precautions, places others at risk for hospital-associated transmission. Detection of a single such infection should prompt further investigation and actions to mitigate risk to other HCP and patients.

The purpose of this document is to assist acute care facilities with responding when hospital-associated transmission of SARS-CoV-2 is suspected, including assessing risk to HCP and patients potentially exposed while in the facility. This document is intended for use by acute care facility staff, infection prevention and control (IPC) staff, and public health officials. Guidance for responding to SARS-CoV-2 in nursing homes is available here.

Additional key resources

Determining when an individual is potentially infectious

The time period when an individual (e.g., healthcare provider, patient) with SARS-CoV-2 infection could have been infectious is defined in the Interim U.S. Guidance for Risk Assessment and Work Restrictions for Healthcare Personnel with Potential Exposure to COVID-19:

Definition of potential exposure to SARS-CoV-2

Potential exposures in acute care settings occur most commonly when

  • HCP with SARS-CoV-2 infection work while infectious.
  • Patients with possible SARS-CoV-2 infection are not immediately identified (e.g., negative SARS-CoV-2 viral test at admission, managed without Transmission-Based Precautions, but later diagnosed with SARS-CoV-2 infection via a positive viral test).

Information to gather once an infected healthcare provider or patient is identified

Identification of a healthcare provider or patient with a new SARS-CoV-2 infection should prompt further investigation to determine if others in the facility could have been exposed.

Information to gather regarding an infected healthcare provider could include (if applicable):

  1. Date of COVID-19 symptom onset
  2. Date of first positive SARS-CoV-2 viral test
  3. Dates and times the healthcare provider worked while potentially infectious
  4. Areas where the healthcare provider worked while potentially infectious
    1. Does the healthcare provider work at other healthcare facilities?
  5. Names of exposed patients
    1. What was the infected healthcare provider using for source control or for PPE?
    2. What was the exposed patient wearing for source control?
    3. Where are the exposed patients now (e.g., still in the facility, transferred to another healthcare facility, discharged to home)?
  6. Names of exposed HCP (e.g., nurses, physicians, therapists, technicians)
    1. What was the nature of the interaction (e.g., did higher risk interactions occur, such as being in the same room or socializing while not wearing a mask or eating together)?
    2. What were the infected and exposed HCP using for source control or for PPE?
  7. Names of others, including visitors, who may have been exposed
    1. What was the nature of the interaction?
    2. What were the infected HCP and exposed person using for source control or for PPE?
  8. Information on potential source(s) of infection
    1. Was there unprotected contact with a person suspected (e.g., person with viral respiratory symptoms) or confirmed to have SARS-CoV-2 infection outside the facility in the last 14 days?
    2. Was there any recent travel or attendance at social gatherings in the last 14 days?
    3. Was care provided for suspected or confirmed SARS-CoV-2 patients in the last 14 days?
      1. If yes, were appropriate infection prevention and control practices utilized (e.g., appropriate PPE)?

Information to gather regarding an infected patient could include (if applicable):

  1. Date of COVID-19 symptom onset
  2. Date of first positive SARS-CoV-2 viral test
  3. Date of admission or date of outpatient encounter
  4. Source of admission (e.g., home, nursing home)
  5. Date(s) when Transmission-Based Precautions for SARS-CoV-2 were implemented and maintained
  6. Where the patient had been in the facility while potentially infectious and not on Transmission-Based Precautions
    1. Types and dates of care received (e.g., procedures, surgeries, aerosol generating procedures)
  7. Names of roommates or other exposed patients (e.g., present during intubation in open Emergency Department area)
    1. What were the infected and exposed patients wearing for source control?
    2. Where are the exposed patients now (e.g., still in the facility, transferred to another healthcare facility, discharged to home)?
  8. Names of potentially exposed HCP (e.g., nurses, physicians, therapists, technicians)
    1. What was the nature of the interaction?
    2. What was the infected patient wearing for source control?
    3. What was the exposed provider using for source control or for PPE?
  9. Names of others, including visitors, who may have been exposed
    1. What was the nature of the interaction?
    2. What were the infected HCP and exposed person using for source control or for PPE?
  10. Information about potential source(s) of infection
    1. Was there contact with a person suspected (e.g., person with viral respiratory symptoms) or confirmed to have SARS-CoV-2 infection in the last 14 days, outside or inside of the facility?
    2. Was there any recent travel or attendance at social gatherings in the last 14 days?

Assessing risk to exposed healthcare personnel and patients

Although HCP or patients may be in close contact with an infectious individual for enough time to be considered exposed, the risk for transmission is also influenced by the nature of the interaction and the presence or absence of mitigating factors (e.g., use of source control, PPE).

Assessing risk to exposed healthcare personnel and patients

Assessing risk to exposed patients

  • Mirroring the risk assessment guidance for HCP, the following situations likely constitute a higher risk for SARS-CoV-2 transmission to patients:
    • The infected individual did not wear anything for source control.
    • The exposed patient did not use a facemask that covered their nose and mouth for the entire duration of the exposure.
    • The exposed patient was in the same enclosed space while the infected individual underwent an aerosol-generating procedure (e.g., a patient remained in the room while their infected roommate received continuous positive airway pressure therapy (CPAP)).

Managing exposed healthcare personnel and patients

Ideally, all HCP and patients that meet the exposure criteria above should be notified about their exposure. Patients currently admitted to the facility or transferred to another healthcare facility should be prioritized for notification. Both HCP and patients, if infected, have the potential to expose a large number of individuals at higher risk for severe disease or they can be at higher risk for severe disease themselves. Information about exposed visitors can be provided to the local health department or other appropriate public health contacts for assistance with notifications, assessments, and follow-up.

Managing exposed healthcare personnel

Exposed HCP should be managed (e.g., work restrictions) according to the Interim U.S. Guidance for Risk Assessment and Work Restrictions for Healthcare Personnel with Potential Exposure to COVID-19.

Managing exposed patients

In general, exposed patients should be:

  • Quarantined for 14 days after their last exposure.
    • Currently admitted patients should be placed in a single patient room and managed with Transmission-Based Precautions used for patients with suspected or confirmed SARS-CoV-2 infection.
      • Patients should not be transferred to a COVID-19 unit unless they are confirmed to have SARS-CoV-2 infection.
      • Monitor these patients at least daily for signs and symptoms of COVID-19. Patients who develop signs or symptoms consistent with COVID-19 should be tested for SARS-CoV-2 infection with a viral test and managed appropriately depending on the results.
    • Exposed patients who are being discharged or transferred to another healthcare facility should remain in home quarantine or in appropriate Transmission-Based Precautions for 14 days following their last exposure, respectively. They should be advised about who to contact if they develop signs or symptoms of COVID-19.
    • Alternatives to the 14-day quarantine period in healthcare settings are described in the FAQ, “Are the alternatives to the 14-day quarantine described in the Options to Reduce Quarantine for Contacts of Persons with SARS-CoV-2 Infection Using Symptom Monitoring and Diagnostic Testing recommended for healthcare facilities?

Note: if resources are limited, mirroring guidance for exposures among HCP, quarantine and testing (as described below) might be reserved for patients with higher risk exposures. All exposed patients should be followed for 14 days for the development of symptoms and should be tested for SARS-CoV-2 infection if compatible symptoms develop.

Viral testing of asymptomatic exposed healthcare personnel and patients

Testing asymptomatic exposed healthcare personnel

Testing asymptomatic exposed patients

Responding to potential hospital-associated transmission

Identifying hospital-associated transmission

Although it can be challenging to identify hospital-associated transmission because of the incubation period and potential for asymptomatic infections, at a minimum, hospital-associated transmission should be considered when any of the following occur:

  • Onset of SARS-CoV-2 infection in a patient occurring more than 14 days after admission; of note, onset of SARS-CoV-2 infection after a shorter period (e.g., ≥ 2 days) could still indicate healthcare-associated transmission.
  • Two or more SARS-CoV-2 infections are identified among epidemiologically linked HCP or patients (e.g., those working or residing on the same unit).

Additional infection prevention and control actions to consider when hospital-associated transmission is suspected

Depending on the suspected extent of transmission, additional IPC actions may be needed when hospital-associated transmission is suspected. State or local public health departments should be notified about any suspected hospital-associated transmission according to state and local regulations. Additional IPC actions to consider include:

  • Conducting IPC assessment of affected units or departments to identify gaps that require mitigation.
  • Notifying facility leadership and local or state public health departments.
  • Temporarily halting admissions or non-essential services (e.g., elective procedures, non-urgent admissions) in affected units and departments until the extent of transmission can be determined, prevention measures have been evaluated for adequacy, and lapses have been mitigated.
    • Consider restricting the use of areas in the facility where HCP or patients may gather (e.g., facility cafeteria and waiting areas).
    • Consider restricting HCP movement and work between units.
    • Factors to consider when deciding to resume admissions or non-essential services include decreasing transmission in the facility, community impact, mitigation of identified IPC gaps, resolution of staffing shortages, and others, in consultation with state and local public health departments.
  • Expanding the use of Transmission-Based Precautions recommended for SARS-CoV-2 to other patients who were not known to be exposed, but may be at risk for transmission. This could include patients in the same area or on the same service (e.g., shared HCP with infected patients), or all patients on units or departments with suspected hospital-associated transmission, until there are no new cases for 14 days.

Expanded viral testing of healthcare personnel and patients when hospital-associated transmission is suspected

  • Consider expanded testing of HCP and patients as determined by the distribution and numbers of cases throughout the facility.
    • Depending on testing resources available or the likelihood of healthcare-associated transmission, facilities may elect to initially expand testing only to HCP and patients on the affected units or departments, as opposed to the entire facility. If an expanded testing approach is taken and testing identifies additional infections, testing should be expanded even more broadly.
    • If possible, repeat testing every 3-7 days until no new cases are identified for at least 14 days.

Strategies for early identification and prevention of hospital-associated transmission

Adherence to recommended infection prevention and control practices, including use of source control in healthcare settings, can help prevent hospital-associated transmission. Auditing IPC practices provides the opportunity to both ensure HCP are appropriately implementing recommended practices and to remediate any lapses identified. Hospitals might also consider routine SARS-CoV-2 testing for all patients upon admission, ideally with a highly sensitive molecular test. This approach can be labor-intensive and costly and is subject to several limitations, including the possibility of false negative test results and obtaining negative results for patients who are in their incubation period and who later become infectious. To increase detection of patients who might have been in the incubation period at the time of admission, consideration could be given to repeat testing 3-5 days after admission.

Definitions

Aerosol Generating Procedures: Defined in the key resource listed above, in the CDC FAQ, “Which procedures are considered aerosol generating procedures in healthcare settings?

Healthcare Personnel (HCP): HCP refers to all paid and unpaid persons who are serving in healthcare settings and who have the potential for direct or indirect exposure to patients or infectious materials, including body substances (e.g., blood, tissue, specific body fluids); contaminated medical supplies, devices, and equipment; contaminated environmental surfaces; or contaminated air. HCP include, but are not limited to, emergency medical service personnel, nurses, nursing assistants, physicians, technicians, therapists, phlebotomists, pharmacists, students and trainees, contractual staff not employed by the healthcare facility, and persons who do not directly provide hands-on patient care (e.g., clerical, dietary, environmental services, laundry, security, engineering and facilities management, administrative, billing, volunteer personnel).

Facemask: Facemasks are PPE and are often referred to as surgical masks or procedure masks. Use facemasks according to product labeling and local, state, and federal requirements. FDA-cleared surgical masks are designed to protect against splashes and sprays and are prioritized for use when such exposures are anticipated, including during surgical procedures. Facemasks that are not regulated by FDA, such as some procedure masks, which are typically used for isolation purposes, may not provide protection against splashes and sprays.