Updated Testing Guidance Based Upon Progress with COVID-19 Vaccination
HCP1 working in hospitals remain at potential risk for SARS-CoV-2 exposures both in the community and in their workplace. Infected HCP can transmit to other HCP (through close contact in break rooms and other common areas) as well as their patients. In December 2020, CDPH recommended routine SARS-CoV-2 diagnostic screening testing of hospital HCP to aid in early identification and work exclusion of infected HCP, reduce transmission risk to other HCP and patients, and prevent hospital outbreaks.
HCP were among the first groups prioritized for COVID-19 vaccination as soon as vaccines became available in late December 2020. Estimates of the interim effectiveness of currently authorized mRNA COVID-19 vaccines in preventing SARS-CoV-2 infection range between 86%-90% [1-3], regardless of symptomatic status. Overall COVID-19 incidence statewide, and incidence and outbreaks in healthcare facilities, have declined dramatically since January 2021 and currently remain stably low as of the release of this revised AFL. CDC now no longer recommends routine diagnostic screening testing for asymptomatic HCP who are fully vaccinated (i.e., ≥2 weeks following receipt of the second dose in a 2-dose series, or ≥2 weeks following receipt of one dose of a single-dose vaccine). To sustain the current lowered COVID-19 incidence and to be able to detect and contain transmission promptly in the event of future surge(s), measures to prevent COVID-19 exposures and transmission among unvaccinated HCP and patients within health facilities remain necessary.
Updated Routine Diagnostic Screening Testing of HCP
Hospitals may discontinue routine diagnostic screening testing of asymptomatic HCP who are fully vaccinated if ≥70%2 of all HCP that work at the facility are fully vaccinated3 otherwise, routine diagnostic screening testing of asymptomatic HCP is recommended for all HCP regardless of their vaccination status. Hospitals that modify their routine diagnostic screening testing program for HCP should prioritize testing all HCP who are unvaccinated or partially vaccinated at a minimum weekly cadence. HCP who had a positive viral test in the past three months and are now asymptomatic do not need to be retested as part of facility-wide testing; testing should be considered again (e.g., in response to an exposure) if it is more than three months after the date of onset of the prior infection, or if new symptoms occur.
Hospitals should implement strategies to increase, maintain, and track vaccination coverage among HCP as high as possible, including verifying vaccination status of new hires, and offering education, listening sessions, counseling, and vaccination at every opportunity, even to those HCP who have previously refused.
Diagnostic Testing for Symptomatic HCP
HCP with signs or symptoms consistent with COVID-19 should be tested immediately, regardless of their vaccination status. GACHs should not delay testing of symptomatic HCP until scheduled diagnostic screening testing. HCP with a prior positive viral test who develop new symptoms consistent with COVID-19 should be tested if it is more than three months after the date of onset of the prior infection; if symptoms develop during the three months after the date of initial symptom onset, if an alternative etiology cannot be identified, then retesting can be considered in consultation with infectious disease or infection control experts.
Response Testing of HCP
Testing should be performed for all HCP regardless of their vaccination status following higher-risk exposures to SARS-CoV-2. Testing also should be performed in response to a cluster of cases meeting the outbreak investigation threshold for hospitals in AFL 20-75. The first round of response testing should be conducted among all potentially exposed patients and HCP regardless of vaccination status as soon as possible after the outbreak investigation threshold is met. After completion of the first round of response testing, perform serial retesting at least weekly with molecular testing or a minimum of twice weekly with antigen testing of all potentially exposed patients and HCP regardless of vaccination status who test negative upon the prior round of testing, until no new cases are identified in sequential rounds of testing over a 14 day period. Hospitals should work with their local health department to guide response testing. Asymptomatic fully vaccinated HCP with higher-risk exposures do not need to be excluded from work following their exposure (AFL 21-08.2).
Testing for Newly Admitted, Newly Symptomatic and Exposed Patients
GACHs may consider modifying testing protocols for patients whose vaccination status is known prior to or upon admission or procedure. The yield of this testing for identifying asymptomatic infection is likely lower among vaccinated patients because a growing body of evidence suggests that fully vaccinated people are less likely to have asymptomatic infection. However, these results might continue to be useful in some situations to inform the type of infection control precautions used (e.g., room assignment/cohorting, or personal protective equipment used). GACHs should continue to test unvaccinated patients and patients whose vaccination status is unknown prior to or upon admission or procedure. GACHs should also continue to monitor all patients for the development of COVID-19 symptoms, and promptly test any newly symptomatic patients and patients who are exposed to a suspected or confirmed case during their hospital stay, regardless of their vaccination status.
Plans for Use and Follow-up of Test Results
CDPH recommends that GACHs that implement HCP testing programs include policies and procedures addressing the use of test results, including:
Procedures for the Duration of Work Exclusion of HCP Who Test Positive
In general, HCP with COVID-19 should be excluded from work for the duration of their isolation period. GACHs should follow CDC Guidance on Mitigating Staffing Shortages, and CDC Return to Work guidance to determine when HCP may return to work.
Hospitals should revise their General Acute Care Hospital COVID-19 Mitigation Testing Plan (PDF) to reflect any changes in practice and have it available for review for CDPH upon request.
GACHs must understand that routine SARS-CoV-2 diagnostic screening testing of HCP does not replace or preclude other infection prevention and control interventions, including monitoring all HCP and patients for signs and symptoms of COVID-19, masking by HCP and patients for source control, maintaining physical distancing and source control in HCP common areas (e.g., breakrooms), use of recommended personal protective equipment (PPE), and environmental cleaning and disinfection. When testing is performed, a negative test only indicates an individual did not have detectable infection at the time of testing; individuals might have SARS-CoV-2 infection that is still in the incubation period or could have ongoing or future exposures that lead to infection.
GACHs may submit any questions about this AFL or about infection prevention and control of COVID-19 to the CDPH Healthcare-Associated Infections Program via email at HAIProgram@cdph.ca.gov or firstname.lastname@example.org.
If you have any questions about state testing prioritization plans, please contact the Testing Taskforce at email@example.com.
Original signed by Cassie Dunham
Acting Deputy Director
CDPH Updated Testing Guidance
Personnel (HCP) refers to all paid and unpaid persons serving in healthcare settings who have the potential for direct or indirect exposure to patients or infectious materials, including body substances (e.g., blood, tissue, and 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, home healthcare personnel, physicians, technicians, therapists, phlebotomists, pharmacists, students and trainees, contractual staff not employed by the healthcare facility, and persons not directly involved in patient care, but who could be exposed to infectious agents that can be transmitted in the healthcare setting (e.g., clerical, dietary, environmental services, laundry, security, engineering and facilities management, administrative, billing, and volunteer personnel).
2A threshold of 70% was chosen based upon modeling tools that predict the impact vaccination and testing strategies can have on SARS-CoV-2 outbreaks in workplaces, which show a diminished role for routine diagnostic screening testing to prevent and limit outbreaks past a threshold of 70% vaccination coverage among workers. See Testing and vaccines model.
3Fully vaccinated is defined as ≥2 weeks following receipt of the second dose in a 2-dose series, or ≥2 weeks following receipt of one dose of a single-dose vaccine; there is currently no post-vaccination time limit on fully vaccinated status.