COVID-19 Decision Trees

The new quarantine guidance issued by CDPH and group tracing model are now reflected in the latest COVID-19 decision tree, updated Jan. 19 at 10 a.m. The Spanish version is also current. If you are not seeing the most current version of the decision tree, please clear your internet cache, reload the page, and download the correct version. The decision tree will be updated as needed to reflect the latest public health guidance. Please check this page weekly to ensure you are using the latest version.

The e-Decision Tree (last updated Jan. 19) is a digital representation of the San Diego County COVID-19 K-12 Decision Trees developed by the San Diego Supercomputer Center, UC San Diego in collaboration with the UC San Diego School of Medicine Division of Child and Community Health, and the San Diego County Office of Education. The e-Decision Tree has been updated to include the new “group tracing” option and is now able to calculate dates for testing and return for household exposures.

Please see below for the most recent changes to the Decision Trees.

COVID-19 Decision Trees FAQ


English PDF (current)

Spanish PDF (current)

COMMON TERMS

1. What is the difference between quarantine and isolation?

Quarantine: People who have been identified as having been in close contact with someone with COVID-19 are required to quarantine away from others because they may become infected with COVID-19 from 2 to 14 days following their last contact with a person who had COVID-19 (see question 3 for options for duration of quarantine).

Isolation: People who have one or more of the symptoms associated with COVID-19 and/or have lab confirmed COVID-19 are required to isolate away from others while they may be contagious with COVID-19. A person:

  • With symptoms is considered to be contagious from 2 days before their symptoms began, to 10 days after.
  • Who has tested positive and does not have symptoms is considered contagious from 2 days before the date their first positive test sample was collected until 10 days after, if they remain asymptomatic.
  • Who tested positive while they were asymptomatic, and develops symptoms later, is considered contagious from 2 days before the first positive test sample was collected until 10 days after their symptoms began.

2. What is the definition of close contact?

A person is considered to be a close contact if they were within 6 feet of a person who was contagious with COVID-19 for a total of 15 minutes or more in a 24-hour period.

  • This is true for exposure that occurred indoors or outside, with masks on or off.
    • NOTE: Time spent within 6 feet by a person who is wearing a “fit tested” N95 respirator does not count toward close contact identification.
  • A person who has COVID-19 is considered to be contagious from 2 days before their symptoms began (or before their first positive test if they never developed symptoms) until 10 days after.

3. What is the difference between individual contact tracing and group tracing?

Individual contact tracing involves identifying the people in the school who were in close contact with a person who was contagious with COVID-19. Close contacts are then assigned to quarantine based on their vaccination status, the circumstances of the contact, and their willingness and ability to provide evidence of a negative test taken within specific timeframes.

In group tracing, the school identifies the students that shared a common indoor airspace with a person who was contagious for COVID-19. The school then provides notice to these students (vaccinated and unvaccinated) that they were part of an exposed group on a specific date, and that they are required to test on Day 3, 4, or 5 following that exposure. Students who participate in testing on Day 3, 4, or 5 are permitted to remain in school and continue all school activities unless they develop symptoms or receive a positive test result. Schools are not required to track testing results, and can rely on parents to report positives.

When group tracing is used, students are only required to remain home if they:

  • Inform the school that they are unwilling to test as required
  • Have one or more of the symptoms associated with COVID-19, or test positive
  • Live with someone who has COVID-19

For K-12 workers, schools are required to use individual contact tracing, and the quarantine options described in the COVID-19 K-12 Decision Trees.

INDIVIDUAL CONTACT TRACING, CLOSE CONTACTS, AND QUARANTINE

4. Who is exempt from quarantine requirements?

Per CDPH guidance, there are different requirements for K-12 workers and students:

Student close contacts who do not have symptoms are not required to quarantine if they provide evidence that they:

  • Are fully vaccinated (at least 14 days past their second dose of Pfizer or Moderna, or single dose of J&J) OR
  • Are within 90 days of symptom onset from a lab-confirmed case of COVID-19, or a positive lab test if the person never developed symptoms..

Employee close contacts who do not have symptoms are not required to quarantine if they provide evidence that they:

  • Have received their booster dose, or who have completed their primary vaccine series and are not yet eligible for a booster. To remain at work, people in this category must wear a mask that fits snugly over their nose and mouth indoors, and when within 6 feet of others outside, through Day 10. Testing is also recommended (but not required) on Day 5. If an employee close contact is unable to mask as required, quarantine at home is required with return to work on Day 11.
    • Employees who are within 90 days of symptom onset from a lab-confirmed case of COVID-19, or a positive lab test if the person never developed symptoms, may also use this provision.

If symptoms occur in anyone (student or K-12 worker) during quarantine (even people who are fully vaccinated, and those who have already had COVID-19 in the preceding 90 days), they are required to self-isolate immediately. We also recommend they get tested and, if symptoms worsen, contact their health care provider. They may also consider testing for earlier return (on Days 6 – 10) from isolation.

5. Is contact tracing required for students in outdoor settings?

Based on updated guidance from the CDPH, if a school opts to use individual contact tracing, it does not need to identify encounters in unstructured outdoor settings. Focus on:

  • Encounters in indoors and enclosed outdoor spaces (e.g., 3+ sided tents)
  • Structured outdoor settings (e.g., PE, athletics, band, before- and after-school programs)
    • A structured setting is any setting in which an adult is responsible for a roster of students who are specifically assigned to them
  • The people the student normally associates with, including time spent within 6 feet in unstructured outdoor settings.

6. What are the requirements for quarantine when a member of a household has COVID-19?

K-12 workers and students identified as having been in close contact with a person who has COVID-19 are required to quarantine as described on the decision tree from the date of their last contact with a person who is contagious. (People are considered to be contagious from 2 days before their symptoms began, [or if they remain asymptomatic, the date on which their first positive test sample was collected] to 10 days after.)

When a member of a household has COVID-19, all members of the household who are not otherwise exempt from quarantine are required to quarantine at home until the COVID-positive household member’s isolation period has ended, plus the number of days required for the quarantine option that they’re authorized to use (see question 4). If the COVID-positive household member is able to end their isolation on Day 6 (or later with a negative test result from a sample collected on or after Day 5) , the quarantine period of close contacts in the household can begin on that day.

If another member(s) of the household develops COVID-19 during the quarantine period, quarantine for all members of the household who are not exempt must be extended based on the new exposure.

7. Can a COVID-positive household member isolate themselves in a room in their home to reduce the overall length of quarantine of others who live in the home?

If the COVID-positive person is not able to isolate in a separate residence, the county’s home isolation instructions (translations) describe the specific requirements for isolation in a home occupied by others. If the person is able to comply with these instructions, quarantine of close contacts can begin when the COVID-19-positive person begins isolation.

8. Are schools required to make modified (in school) quarantine available for their students who meet the criteria for it?

Item 8 of the California Department of Public Health (CDPH) school guidance characterizes modified quarantine as a “recommendation for unvaccinated students for exposures when both parties were wearing a mask, as required in K-12 indoor settings.” Schools are encouraged to use this option, but are not required to do so.

9. Can students in modified (in school) quarantine participate in before- and after-school expanded learning and childcare programs?

Based on recent information from the Safe Schools for All team and the Community Care Licensing Division, children who are permitted to attend school during modified quarantine may continue to participate in before- and after-school expanded learning programs and child care, as long as those programs are provided on their school campus and activities are similar to those in the regular school day. Students in modified quarantine are required to quarantine at home from all other before-school, after-school, and weekend activities, including but not limited to athletics programs, band/music, dance, cheerleading, drama, clubs, and visiting any settings where non-household members are present. Activities may resume on or after Day 6 provided they have remained asymptomatic and have evidence of a negative test sample collected on or after Day 5.

GROUP TRACING

10. Are schools able to choose individual or group tracing?

For students, schools have the option to use the individual contact tracing methods that have been used since schools returned to in-person learning, or to shift to the group tracing approach described by the CDPH. Schools are not required to shift to group tracing.

11. Can a school use individual and group tracing?

It is possible to use individual and group tracing, with group tracing as the primary approach, and individual contact tracing reserved for higher-risk exposures. For example, individual contact tracing and quarantine would be appropriate for protecting students in a classroom that serves medically fragile students.

12. Are schools able to mix requirements from the individual and group tracing models?

No. Each model has specific requirements and rules.

  • Tracking test results: In group tracing, schools are not required to track student test results related to group tracing notices – parents are required to report positives. In the individual tracing model, schools must require proof of results related to quarantine.
  • Quarantine: In group tracing, students who are a part of an exposed group remain in school with testing required on Day 3, 4, or 5. In individual contact tracing, students are required to quarantine and test according to the option that fits their circumstances. Group tracing can only be used with students. Individual tracing can be used with students and must be used with employees.
  • Exemption from Close Contact Testing: In the group tracing model, all students (including fully vaccinated students and those within 90 days of a prior lab-confirmed COVID-19 diagnosis) are required to test on day 3, 4, or 5, to remain in school and participate in extracurricular activities. In the individual tracing model, students who are 14 days past completion of their primary vaccine series, and those within 90 days of a prior lab-confirmed COVID-19 diagnosis are exempt from testing following close contact.

13. Are students who are at least 14 days past completion of their primary COVID-19 vaccination series, or within 90 days of a prior lab-confirmed infection, exempt from the requirement that they test on Day 3, 4, or 5?

No. Per the CDPH guidance on group tracing, when group tracing is used, all students who shared a common airspace with a person who was contagious with COVID-19 for 15 minutes or more in a 24-hour period are required to test on Day 3, 4, or 5 to remain in school. This includes students who are fully vaccinated and those who have recovered from a prior lab-confirmed infection within the last 90 days.

14. If the guidance on group tracing says students in an exposed group should test on day 3, 4, or 5, why does the decision tree say they are required to test?

While guidance does use the word should, it goes on to state that "Exposed students who participate in testing may continue to take part in all aspects of K-12 schooling, including sports and extracurricular activities, unless they develop symptoms or test positive for COVID-19." By extension, students who do not participate in testing may not continue to take part in all aspects of K-12 schooling.

15. Are schools required to see evidence of negative test results from students who are required to test as part of an exposed group?

No. Schools are not required to track test results. Parents are expected to inform the school when their child tests positive or develops symptoms.

ISOLATION

16. How should schools manage eating and drinking for students who return from isolation before Day 11?

Students who return from isolation before Day 11 are required to wear a mask that fits snugly over their nose and mouth indoors, and outside when they are within 6 feet of others on Days 6 through 10 from the onset of their symptoms. Schools should arrange for students to eat and drink outside with physical distancing.

17. Can students who return from isolation before Day 11 participate in before- and after-school programs and activities on Days 6 through 10?

Children who are permitted to return to school from isolation before Day 11 may participate in before- and after-school expanded learning programs and child care, however they must wear a mask that fits snugly over their nose and mouth indoors and when within 6 feet of others outside.

Participation in other after-school activities is not prohibited, but it’s also not advisable. People who are recovering from COVID-19 continue to be contagious for 10 days past the onset of their symptoms. A negative test on Day 5 indicates that the risk of transmission is lower, not eliminated. That’s why there are no exemptions or exceptions to the requirement that a mask must be worn indoors and when around others outside. If a student is unable or unwilling to mask as required, they must continue isolation through the end of Day 10.

18. Can student athletes who return from isolation before Day 11 practice and compete on Days 6 through 10 if they commit to wearing a mask as required?

It is not prohibited, but it’s also not advisable. A negative test result on Day 5 after symptom onset does not mean there is no virus in the person. It means that their viral load is low enough to reduce the chances of transmission while they are wearing a well-fitted mask. During exercise people exhale heavily, making their mask less effective, and increasing the chance of transmission. Limiting students who have returned from isolation to “walk-through” activities is advisable on Days 6 through 10.

19. Can musicians who return from isolation before Day 11 practice or perform on Days 6 through 10 if they use a bell cover over their instrument?

No. Students who return from isolation before Day 11 are required to wear a mask that fits snugly over their nose and mouth, indoors and outside when they are within 6 feet of others. There are no exceptions to this rule.

TESTING

20. When is confirmation of an antigen test result necessary?

Positive antigen test results, including positive at-home test results, do not require confirmation with a PCR or other NAAT.

  • The decision tree for Asymptomatic Positive individuals has been updated, removing PCR confirmation as a means of verifying a positive antigen test result from a person who does not have symptoms.
  • For people with symptoms, a negative antigen result requires confirmation with PCR or other NAAT to end isolation. If evidence of a negative confirmation test is not provided, isolation must be continued for a minimum of 5 days with return possible on Days 6 through 10, with evidence of a negative test result (antigen, PCR, or other NAAT) provided before return, from a sample collected on Days 5 through 10, or on Day 11 without a test.

21. Why is it still necessary to confirm a negative antigen result from a symptomatic person with a PCR or other NAAT?

A recent revision of the CDPH testing guidance suggested that antigen test results do not need confirmation provided that clinical assessment of the person’s symptoms was consistent with antigen test results, or modified if there was a “high-risk” exposure, but a list of concerning symptoms and high-risk exposures was not provided. In the absence of this information, the County of San Diego requires that schools continue to confirm negative findings when antigen tests are used with people in response to an onset of symptoms associated with symptoms. (Negative antigen results do not require PCR confirmation being used to determine if a person can end isolation on days 6 – 10.)

22. Can at-home testing be used to satisfy testing requirements?

STUDENTS: Schools may accept the results of at-home testing for the same uses for which antigen tests are approved. Schools are encouraged to use a means described in the Over-The-Counter Tests Guidance to verify the results on tests administered at home. See the “What are best practices for verification of self-test results?” section for specific recommendations.

EMPLOYEES: Per Cal/OSHA, an employer may only accept the results of an at-home test when the administration is observed by the employer or a telehealth proctor.

STUDENTS and EMPLOYEES: When used for a person who has symptoms, the County of San Diego requires that a negative antigen test be confirmed by a follow-up PCR or other NAAT, and that the person isolate pending the result of that test.

23. What are the requirements if a person tests positive but has no symptoms?

If the person remains asymptomatic, they are required to self-isolate for at least 5 days past the date on which the positive test was collected. To return to school or work the person must wear a mask that fits snugly over their nose and mouth, indoors and within 6 feet of others outside, on Days 6 through 10. If the person is unable or unwilling to do this, they must remain in isolation through Day 10.

If the person develops symptoms, isolation must be extended until 10 days have passed since the onset of symptoms.

24. If a person who has symptoms is within 90 days of a previous lab-confirmed COVID-19 diagnosis receives a negative antigen result, can they remain in school/work without PCR confirmation?

Under normal circumstances a person who is antigen negative in response to the onset of symptoms must obtain a negative PCR result from a sample collected within 48 hours of symptom onset to return to school/work before Day 6. But in the case of a person with symptoms who is antigen negative and within 90 days of previous lab-confirmed COVID-19 diagnosis, a PCR test may still detect the prior infection.

When these circumstances are present, the person may consider getting PCR confirmation of the negative Antigen test.

  • If the result is negative, the person may return to work or school when the person has been free of fever for at least 24 hours without the use of fever-reducing medications, and their symptom are improving.
  • If the PCR test is positive or is not done, the person may contact their physician to discuss their symptoms and history. Return to school or work may be authorized by the physician with evidence of a negative antigen test, when the person has been free of fever for at least 24 hours without the use of fever-reducing medications, and their symptom are improving.
  • Otherwise, the person can return according to the criteria for return from isolation on Day 6 or 11.

25. Why should students test if it's recommended but not required?

The 10-day quarantine option allows close contacts who have remained asymptomatic to return on Day 11 without testing, but a test on day 5, 6, or 7 is recommended (not required), so why do it?

  • Because people can transmit the virus at least 2 days before developing symptoms, discovering that a child is positive early can prevent many of their friends, classmates, and co-workers from having to quarantine. It reduces the chance that they might pass the virus on to others.
  • If a student tests positive, they will have to self-isolate for 5 to 10 days (depending on the circumstances) from the date the sample was collected that tested positive. But when they have recovered, they will not be required to quarantine following close contact for 90 days from when their symptoms started.

VACCINATION STATUS

26. Has the standard for being fully vaccinated changed?

The term “fully vaccinated” has not been redefined, but some of the quarantine requirements for K-12 workers now consider whether a person has received a booster dose if they are eligible to receive one.

27. Do K-12 workers who are booster eligible and not boosted need to test weekly?

No. The weekly testing requirement is described in the state public health officer order (Aug. 11, 2021), which has not been updated since it was issued.

REQUIREMENTS VERSUS RECOMMENDATIONS

28. Why are some of the CDC’s recommendations not included in the decision trees?

While the Centers for Disease Control and Prevention (CDC) makes recommendations, the requirements for California schools are established by the CDPH and the school’s local health jurisdiction. The decision tree is based on the CDPH K-12 guidance and related FAQ, K-12 Testing Strategies, Cal/OSHA Emergency Temporary Standards, the local public health orders, pertinent executive orders, and answers received directly from the CDPH.

29. The CDPH says the quarantine options described in their guidance are only "recommendations." Is quarantine optional?

Quarantine is not optional. The County public health order states, "Household contacts, intimate partners, caregivers, and any other person who have been in close contact with a person either diagnosed with COVID-19, or likely to have COVID-19 (COVID-19 Patient), must quarantine themselve" following community exposures. The Order defers to the CDPH K-12 guidance for school exposures that allow modified and shortened quarantine options with testing.

Recent Decision Tree Changes

Jan. 19
 
Page 1
  • Summary of changes box added at the top
 
Page 4
  • Test Types By Situation Chart reordered
  • Return from Isolation before Day 11 text changed to "Antigen testing is recommended for people whose symptoms are resolving to determine if they can return to school or work on Day 6 - 10. Antigen tests are less likely to detect virus beyond a person's contagious period.”
  • “For initial testing in response to symptoms” was added to “Person with symptoms” AND text changed to: "Antigen testing is acceptable in response to an onset of symptoms, but if the person with symptoms receives a negative result from an antigen test, they must remain in isolation pending the outcome of a confirmatory PCR test (or other NAAT) administered within 48 hours of symptom onset. If the confirmatory test is also negative the person may return to school or work immediately."
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