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EDMUND G. BROWN JR.
Governor

State of California—Health and Human Services Agency
California Department of Public Health


June 8, 2022


TO:
Local Health Departments

SUBJECT:
Non-Healthcare Congregate Facilities COVID-19 Outbreak Definitions and Reporting Guidance for Local Health Departments



Updates as of June 8, 2022:

  • Updated outbreak definitions for local health department reporting to CDPH.
  • Clarified thresholds for reporting to local health departments.
  • Added considerations for local health departments in determining which reported clusters or outbreaks to prioritize for investigation.

This document provides guidance to local health departments on COVID-19 outbreak reporting requirements and recommendations for non-healthcare settings. This includes requirements for when facilities must report to local health departments (reporting thresholds), and outbreak definitions to determine when local health departments should report to CDPH.

Apart from these specific requirements, local health departments may make determinations on how to prioritize investigation and response to reported clusters or outbreaks; additional considerations for doing so are included below.  

For additional guidance on outbreak reporting in workplaces, local health departments should consult AB 685 COVID-19 Workplace Outbreak Reporting Requirements.

COVID-19 Outbreak Definitions for Non-Healthcare Settings

These outbreak definitions are used to determine when local health departments should report a COVID-19 outbreak to CDPH for surveillance purposes.

  • In residential congregate settings such as dormitories, group homes, boarding houses, overnight camps, barracks, shelters, jails or prisons:

    • At least three suspected, probable, or confirmed COVID-19 cases* within a 14-day period among epidemiologically linked† residents and/or staff, OR
    • For large settings (residential congregate facilities with >100 persons present in the setting), particularly during high levels of community transmission, local health departments may determine that a higher proportion (at least 5%) of cases within a 14–day period may be appropriate for defining an outbreak, even in the absence of identifiable epidemiological linkages.
  • In non-residential congregate settings, e.g., adult and child daycare facilities, K–12 schools, colleges/universities, and all other non-healthcare workplaces:

    • At least three suspected, probable, or confirmed COVID-19 cases* within a 14-day period among people who are epidemiologically linked† in the setting, and are not known to be close contacts‡ of each other in any other case investigation, OR
    • For large settings (a facility or workplace with >100 persons present in the setting), particularly during high levels of community transmission, local health departments may determine that a higher proportion (at least 5%) of cases within a 14-day period may be appropriate for defining an outbreak, even in the absence of identifiable epidemiological linkages.
  • For the above definitions, note that epidemiological linkage may include either known close contact between individuals, OR may include individuals who are members of the same risk cohort (for example, students in the same classroom, or colleagues who work in the same area), even without identified close contact.

Local Health Departments Reporting Outbreaks to CDPH

  • Local health departments that determine that a cluster of COVID-19 cases constitutes an outbreak, using the definitions above, should report the outbreak to CDPH using the Novel Coronavirus 2019 disease outbreak condition in CalREDIE, the exposure event module in CalCONNECT or an alternate established process.

Reporting Thresholds from Settings to Local Health Departments

  • For workplace settings, when three cases among workers are identified in a workplace within a 14-day period, employers are required by AB 685 to notify the local health department.  See AB 685 employer and LHD reporting guidance for additional information.
  • For settings where non-workers are present (i.e., schools, residential settings, or other settings where members of the public are present), local health departments may define reporting thresholds for non-worker cases. For example, a local health department may require a school to report a certain number or proportion of cases among students in a classroom or school, among residents in a shelter or group home, or among attendees of a large event. While three cases in a setting within 14 days may be used as a default, local health departments may wish to vary reporting thresholds for non-worker cases by type of setting and other local considerations.
  • Local health departments should inform settings in their jurisdictions about reporting thresholds and instruct them to notify the local health department if they identify the number of cases that meets the setting specific reporting threshold.

When cases meeting a reporting threshold are reported to the local health department, the local health department will determine if further investigation is warranted; and if investigated, whether the cases constitute an outbreak using the definitions above. Local health departments may set their own criteria to determine which reported clusters warrant additional investigation and outbreak response. They may wish to consider factors such as size of the outbreak, settings and groups at increased risk, proportion of individuals testing positive, vulnerability of affected individuals, and/or other factors such as those described by CSTE, CDC, and CDPH.

Non-COVID-19 Respiratory Outbreaks

  • If laboratory testing in a non-healthcare congregate setting has identified an outbreak of another laboratory-confirmed respiratory viral infection (not COVID-19), the CDPH Influenza and Respiratory Illness Outbreak Quicksheet (PDF) should be used instead of this document. If COVID-19 testing has not been done, it may also be considered in these situations.

Footnotes

* Per the CSTE COVID-19 2021 Case Definition (Aug 24, 2021):

Confirmed case: Meets confirmatory laboratory evidence (detection of SARS-CoV-2 RNA in a clinical or autopsy specimen using a molecular amplification test).

Probable case: Meets clinical criteria AND epidemiologic linkage‡ with no confirmatory lab testing performed for SARS-CoV-2; OR meets presumptive laboratory evidence (detection of SARS-CoV-2 by antigen test in a respiratory specimen); OR meets vital records criteria with no confirmatory laboratory evidence for SARS-CoV-2

Suspect case: Meets supportive laboratory evidence with no prior history of being a confirmed or probable case.

† Epidemiologically-linked cases include persons with close contact‡ with a confirmed or probable case of COVID-19 disease; OR a member of a risk cohort as defined by public health authorities during an outbreak.  A "risk cohort" includes persons with potential for shared exposure with the case(s) through a shared defined physical space. Examples include but are not limited to persons in the same: classroom, school, extracurricular activity, work-shift, physical workspace or living/sleeping space.

‡ See CDPH Guidance for Isolation and Quarantine for definition of "close contact."

 

Originally Published on May 18, 2020