At Vault Health, our mission is to make better health outcomes more accessible and affordable for everyone. This includes adolescents and children in the face of a pandemic. In the past 16 months, we have implemented surveillance testing models at a multitude of schools across the United States. From these experiences, we have found what works (and does not work) across a number of surveillance testing models.
Surveillance testing is particularly important to consider for the upcoming 2021-2022 school year. On July 9, 2021, the Centers for Disease Control and Prevention (CDC) strongly recommended that K-12 schools return to in-person learning, ending a period of at-home and hybrid learning environments attributable to the COVID-19 pandemic. Also, many universities are returning to in-person learning this fall. Although a layered protection approach is needed (e.g., masks, social distancing, ventilation, etc.), a key component of a successful return to in-person learning is surveillance testing. CDC indicated that the implementation strategy falls on school districts, which introduces a number of barriers and challenges. School districts need a testing cadence that balances budgetary restrictions, disruption of classroom and learning activities, and parent and student needs to optimize testing participation and minimize transmission. An adaptable program is also of high importance as COVID-19 continually evolves. A variety of tests and testing modalities are available to help suit these needs
What is surveillance testing?
Surveillance testing is a systematic method of identifying the number of persons infected with a disease at certain time points, in what locations, and in which populations. COVID-19 surveillance testing utilizes viral tests that collect specimens to identify those with active infection and at-risk for spreading the virus. This is a highly effective method of minimizing transmission in schools as it is the only way to identify infected students prior to development of symptoms and isolate them from the rest of the class. The CDC currently recommends that unvaccinated people who attend large social or mass gatherings, especially in crowded indoor settings like schools, get tested. Having a known exposure is not necessary to participate in surveillance testing. Surveillance testing for those vaccinated is not recommended unless they present with COVID-19 symptoms.
And we know surveillance testing works. In a modeling study that examined the effect of different prevention strategies on COVID-19 rates, weekly screening testing reduced secondary cases by a large extent in both elementary and high schools. Surveillances testing was estimated to be most effective in settings where other prevention strategies such as physical distancing and wearing masks were used less (Bilinski et al., 2021).
Another study found that among five school programs with regular surveillance testing (at least weekly), two-thirds of all COVID19 cases were identified through surveillance testing models (Vohra et al., 2021). These models can reassure parents and staff about the safety of in-person learning.
Lesson #1: Different Testing Models
An adaptive model of testing is critical to creating an efficient and purposeful model of COVID-19 surveillance within a school system. Several organizations have released recommendations aimed towards streamlining and troubleshooting testing in schools, such as the Rockefeller Foundation’s State and Territory Alliance for Testing and the Rand Corporation (e.g., developing a task force, securing additional funding).
However, testing processes at a school site should be leveraged to meet the unique needs of the school system. There is not a ‘one size fits all’ solution. The process of establishing and adapting the testing model utilized by a school site should come with flexibility over time to provide a system that is the most appropriate for the age, uptake, acceptability, and risk level of a school’s specific population.
There are a range of testing models that can be used to ensure the health and safety of a student body, including:
Cream of the Crop: This is the most extensive testing model and is a turnkey operation, meaning that Vault Health can customize a program and manage as many aspects as needed. Additional services could include providing tables and chairs, Wi-Fi hotspots and tablets for patient registration, scheduling, medical waste management, and clinical staffing. All aspects of the model will be handled by provider with minimal work from site staff needed.
Mail-in testing: This model offers convenience and parental control, which minimizes impact on the school day and maximizes privacy. Vault Health can virtually supervise specimen collection at home through Zoom and families can directly receive results.
Train-the-trainer: Vault Health can bulk ship kits to the school district and train staff, such as the school nurse or university health services staff, to supervise test administration. Costs include paying for the logistics of the kits, the electronic health records, and lab services. This model reduces costs and allows schools to conduct testing both at regular intervals and immediately when children are symptomatic.
Outbreak plan: This model can be considered the "emergency plan" you break out when/if necessary. Regular testing intervals are not used. Rather in this model, schools can pay a nominal fee up front to set up an action plan if faced with a super-spread event. The school would be set up with an account to order tests on an as-needed basis, and Vault can come in to support as much or as little as the school feels necessary.
Regardless of the model you choose, the most important thing to keep in mind is that this is an iterative process. These models can (and should) be adapted as time progresses. As one private school in California described:
“We started testing because we were gearing up to get back to in person learning. We wanted to test everyone once they were back to have a baseline. We organized a big onsite drive-through and, with time, figured out how to get more efficient with it. So, we then started sending home test kits with the kids. This was so easy that we found that we might as well just do it every two weeks. We continued to do it throughout the 2020-2021 school year. Because of this, we were way ahead of the curve when California came out mandating testing programs for schools. It was really helpful because we were able to start in one model, and adapt as we went. Flexibility with time. This has made us feel optimistic for the Fall 2021 school year; we know how to adapt.”
Lesson #2: Testing Frequencies
A number of considerations should be made when determining the frequency of COVID-19 testing to enact in a school. The number of times (or cadence) a school tests is also an important factor for a strong surveillance system. This testing (and the type of testing) can be altered depending on student behaviors.
Beginning of school year: Return of the student body for the beginning of the school year poses a potential situation in which a student can introduce risk from travel or extracurricular summer activities. Mass testing prior to return to class is a strong strategy for baseline assessment and mitigation before school even begins
During the school year: The school year can comprise of surveillance testing. There are two ways to accomplish this testing:
Pooled testing: This method involves individually testing each student, and mixing all specimens in one analytic sample to determine if there is infection among the group (ex: classroom). Pooled testing causes larger quarantines until reflex testing is complete, which may postpone contact tracing. This method is more cost efficient and is still highly accurate.
Individual testing: This method involves individually testing each student and each sample is analyzed individually to determine exactly who is carrying the disease amongst the class. Once identified, the student(s) can be immediately isolated and contact tracing can begin. This method has higher laboratory costs.
Outbreak: Once an outbreak is identified, cadence testing should be paused for a school-wide testing assessment. Once the outbreak is contained and the two-week quarantine has passed, the school can return to surveillance testing program.
Long breaks: If students are traveling for breaks, schools have found it useful to show documentation that they have a negative test before coming back to school, similar to the beginning of the school year. Students can also use their school test for travel purposes. For higher education students, Vault Health has the ability to sync test results to Clear Pass for convenience at no additional charge.
From our experience at Vault Health, we know that when testing strategies are not evidence-based, they are far less effective than the strategies outlined above. Examples of ineffective strategies that we've found include:
One test at the beginning of the school year,
Long intervals of time between surveillance tests,
Voluntary testing without a reward or disincentive system,
Reactionary testing to concerns voiced by parents.
Regardless of the cadence or time of year, it’s important that schools send HIPAA and FERPA consent paperwork for testing. For example, this can be easily accomplished in the beginning with the Fall orientation packet. This consent should be a blanket testing approval; schools should get the permission for any vendor to test in case one vendor doesn’t work out. Ideally this permission would be electronic and streamlined for each student.
Lesson #3: Test Types
There are many different types of COVID-19 tests offered at Vault Health. Each type of testing is subject to different sensitivity and specificity and the turn-around time it takes to analyze the samples and return results. A balance between these factors must be considered when choosing the test strategy that is best for your school. The model and frequency of tests selection will then determine the best type of test. Broadly there are two types of test: Antigen vs. PCR. And each have important factors to consider:
Antigen tests: Antigen tests detect viral RNA from specimens. Collection is completed using a nasal swab. Antigen tests take approximately 15 minutes to return results, however, sensitivity of results is moderate meaning that some cases of COVID-19 can go undetected. The specificity rate is high, meaning the test does not identify individuals who do not have COVID-19 as positive for the disease. Another consideration for antigen tests is that the farther from onset of disease, the less accurate the test becomes. Exact sensitivity and specificity rates vary by test and manufacturer. Antigen tests are the less expensive option.
PCR tests: PCR (polymerase chain reaction) tests detect viral antigens. Several collection methods are available including throat or nasal swabs, and collection of saliva which is a less invasive and more comfortable option that could be ideal for younger students who may be less likely to cooperate with a swab. Both sensitivity and specificity of PCR tests are classified as high, meaning it is a highly accurate test, but still vary by manufacturer. PCR tests are more expensive and take up to 72 hours for results. However, Vault Health partners with labs that can return results within 48 hours and in most cases, within 12 hours of lab arrival.
It is important to choose a test that is not subject to clinician interpretation, or to consider this factor when selecting which clinician will interpret your tests. Additionally, each test type will be available at a different price points and require different resources.
Lesson #4: Student-Level Considerations
Among school-aged persons, compared to adults, a COVID-19 infection is more commonly asymptomatic or mild. This lack of presentation with typical COVID-19 symptoms poses a risk to school systems which choose to hold on-site classes. Infections can spread despite the asymptomatic nature of the case, which can result in an outbreak. Because many children with COVID-19 are asymptomatic, their infections may be difficult to detect without regular testing.
From Vault Health’s work in testing surveillance, we’ve learned that student body age significantly influences the success of implementation:
Adolescents and Young Adults. The biggest challenge with older students is they need supervision for compliance. In other words, schools need to watch them put the collected sample in the right container for shipping to the lab for test processing. There have been many times where we learned that a student’s peer provided a sample for them. Why? Adolescents are concerned that a positive test would impact their ability to participate in school and extracurricular activities. There are additional considerations needed for student athletes. These students don’t want to test positive and require that their team misses practices or games and have to quarantine. Testing positive comes with bullying or blaming. Older students are more scared of the consequences than the virus itself.
Children. The biggest challenge with younger students is they need supervision for proper sample collection at school and at home.
Lesson #5: School-Level Considerations
School-based surveillance testing may be particularly useful when other prevention strategies are not in place (e.g., masking, physical distancing). Surveillance testing has allowed schools to identify and isolate students with asymptomatic infections and to address potential deficiencies in mitigation protocols, both of which can help reduce transmission of COVID-19.
Many schools prefer the lightest lift possible. Schools are already burdened with limited resources and budgetary restraints. These are some examples of school-level indicators that can help boost student and parent participation:
Voluntary programs are historically not successful in finding true outbreak signals because they introduce a number of biases. For example, a symptomatic person may only seek out testing. However, up to 40% of people with SARS-CoV-2 do not show symptoms, so frequent and rapid testing of large numbers of students is the best way to fend off major outbreaks. For this reason, the CDC recommends systematic testing at least once a week. A study showed that mandatory testing can significantly decrease COVID-19 transmission in universities compared to voluntary testing (Brook et al., 2021).
If voluntary is the only option, schools need to create an environment where participation is socially desirable.
For example, schools can create reward systems (e.g., gift cards) to incentivize parents to consent to their child’s test.
An environment where students won’t be singled out (ex: pooled testing) for a positive test increases testing rates. Stigma around having a positive test and impacting peers' education and participation in extracurricular activities is often a disincentive to participate in testing.
Teachers testing themselves first can set an example and often increases participation.
Schools need to be mindful of program organization. For a testing surveillance system to work, it has to be well-organized. Also, leadership buy-in is key to the success of implementation. For example, a large land grant university has been the most successful client of Vault Health because
“the entire school and leadership completely bought into the program. The testing schedule was based on class schedule, which allowed more than 10,000 students a week, and sometimes more, test for COVID-19. We also trained students to test other students. Keeping fellow students safe. We created a culture that owned surveillance testing within.”
Lesson #6: Epidemiological Considerations
The current level of community transmission, variant spread, and percent vaccinated in your county should be considered when choosing a COVID-19 testing model, frequency, and strategy. Up-to-date information about risk-levels and cases by state and county are provided regularly by the CDC. By triangulating these metrics, schools will have a better sense of the cadence and model needed to implementation.
Community spread. The CDC recommends once a week surveillance testing for schools in moderate to high community transmission areas where there are at least 10 new cases of COVID-19 per 100,000. Schools in low transmission areas do not need to participate in surveillance testing programs according to CDC recommendations.
Vaccinations. The rate of vaccination in the community and the rate of vaccination at the school should significantly influence testing strategies. Schools should feel empowered to ask for vaccination status as routine back-to-school paperwork.
If a student body is at least 85% vaccinated, testing frequency and testing model can be loosened substantially. Among a student body that is <85% vaccinated:
If a student shows proof of vaccination, individual-level testing can be less frequent (i.e., once a month). If no proof of vaccination is provided, testing needs to be more frequent
If leadership prefers not collecting vaccination status in a systematic way, wide spread testing of all students should be considered.
Symptomatic students have to get tested, even if vaccinated.
Overall, it’s clear that schools and leadership have to strike a balance between a number of needs when implementing surveillance testing at schools: cost, privacy, space, parental concerns, and epidemiological landscape. We described a number of models and options in which schools should consider when planning a testing surveillance program for their students. This will not only help curb the pandemic, but ensure a safe environment for students to flourish.
This document draws on Vault Health's experience, CDC guidance, and data-driven, evidence based best practices advised by epidemiologists Dr. Katelyn Jetelina, MPH PhD, Lauren Malthaner, MPH and Alaina Beauchamp, MPH. For more information about educational COVID-19 testing with Vault Health, please send an email to [email protected]
Find our references in our downloadable whitepaper