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COVID-19 | School of Public Health Expert Insights

COVID-19

School of Public Health Expert Insights

Children in schools with masks

Testing in K-12 Schools

A Q&A with Christina Potter and Caitlin Rivers | October 29, 2020


As schools in the U.S. reopen, there is a lack of clear guidance for the safe return of students, teachers, and staff.

Children can transmit the virus to each other and to adults, though rates are still unknown. Because children are often asymptomatic, symptom screenings and temperature checks alone are insufficient to prevent the virus’s spread. 

Regular testing—when done strategically and alongside other efforts including masking and social distancing—can reduce transmission by identifying potential outbreaks early on. 

A new report, Risk Assessment and Testing Protocols for Reducing SARS-CoV-2 Transmission in K-12 Schools, by the Duke-Margolis Center for Health Policy and the Johns Hopkins Center for Health Security with support from the Rockefeller Foundation outlines how schools can screen for and stop or reduce the spread of COVID-19 with an effective testing strategy. The report offers guidelines for school administrators to assess the COVID-19 risk in their schools and can help identify key considerations for developing a screening program to support schools’ efforts to reopen more safely.

In this Q&A, contributing coauthors Caitlin Rivers, PhD, MPH, and Christina Potter, MSPH, from the Johns Hopkins Center for Health Security break down the report. 

Who is this report intended for? 

The report is primarily for school administrators who want to better understand how to assess the risk of SARS-CoV-2 in their school or district, but teachers, parents, and other stakeholders may also find it useful.

Are these guidelines intended for individual schools or entire districts? Who has decision making power? 

Both! Districts usually have responsibility for planning, but schools are where the implementation happens, so they should really have a voice in the planning process too, as should the local health department and teachers and families. Everyone has a part to play. 

Let’s talk about what this report is NOT: It’s not endorsing a testing-only prevention strategy. What other actions should schools be taking? 

Absolutely, testing alone is not enough. Masks, social distancing, hand hygiene, respiratory etiquette (like coughing into your elbow or covering your face with a tissue when you sneeze), cleaning and disinfection, and contact tracing are also important. 

We also recommend that schools consider improving ventilation and implementing a “pod” strategy, where students and staff are grouped in cohorts to reduce the number of contacts. 

What is the link between high transmission of COVID-19 in a community and the potential for an outbreak in a school?

The likelihood that a case is introduced to a school building increases with the burden of disease in the community. But mitigation measures like masks and social distancing can help to prevent a single case from spreading and becoming an outbreak in a school.

What are the three testing approaches listed in the report? 

Diagnostic tests are highly accurate tests, primarily for people with symptoms or reason to believe they may be infected. That is the testing approach used most often right now. 

Screening programs test people regularly, for example once a week, to try to identify cases and outbreaks early. This is a less common approach that we think will help schools and other institutions to operate safely. 

The purpose of the third type of testing, surveillance testing, is not necessarily to find people who are infected but to understand the burden of disease in the population. This approach can help officials understand if mitigation efforts are working or if other measures need to be taken, such as temporarily closing the school. 

Are some testing approaches more expensive/time consuming than others? 

The approaches serve different purposes, so districts should choose a testing strategy that serves their needs. Diagnostic testing should be available in all communities, but whether screening and surveillance testing also have roles will depend on the level of transmission in the community, and school goals and budgets.

What are immediate next steps if someone has symptoms or tests positive? Should everyone be sent home and the school closed?

That’s a question that schools, in consultation with the local health department, should know the answer to prior to reopening for in-person learning. 

Anyone with COVID-like symptoms should stay out of school and receive a diagnostic test. Confirmed cases and their close contacts should also remain out of school until they are cleared to return. The local health department can help districts develop these plans.

The report states that because evidence is still limited, school administrators should expect guidance to evolve. What do you think might change with more experience and evidence?

There’s still so much we don’t know since COVID-19 is a new disease. Testing protocols for SARS-CoV-2 in children need to be further validated. We don’t know the long-term health effects of children infected by SARS-CoV-2. We don’t fully understand how children of different ages may be more or less susceptible to infection or severe disease. 

More importantly, we know much more now than we did a few months ago, so I’m sure we’ll have learned even more in the future about how best to prevent and control the spread of SARS-CoV-2 in school settings. 

What if a school district has limited testing capacity, either due to availability or budget?

That’s something that should be discussed in consultation with the local health department and other local government officials. To start, we recommend that schools make diagnostic testing available to students, staff, and teachers. For example, school districts could provide a list of appropriate testing sites, or help to arrange for testing.

What should parents/caregivers and teachers know?

In order to solve a problem, you have to know there’s a problem in the first place, and in order to know there’s a problem, you have to look for it. 

In the case of COVID-19, some people never develop symptoms—particularly in the case of children—which makes it really hard to easily know if someone is infected without testing them. Diagnostic testing, screening, and surveillance in schools are impactful tools that, in conjunction with mitigation measures, can help schools quickly identify and respond to outbreaks in the school.

Caitlin Rivers, PhD, MPH, is a senior scholar at the Johns Hopkins Center for Health Security.
Christina Potter, MSPH, is an analyst at the Johns Hopkins Center for Health Security.