Schools' role in the spread of SARS-CoV-2

By Nidhi Saha, BDSMay 2 2022Reviewed by Emily Henderson, B.Sc.

The Omicron wave of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)––the causative pathogen for coronavirus disease 2019 (COVID-19) and the current pandemic––led to rampant transmissions in schools. Therefore, the school-based viral transmission must be curtailed to reduce viral evolution and maintain children's in-person education.

The spread of SARS-CoV-2 infections in schools affects not only students present but also the surrounding communities. Consequently, intermittent increases in SARS-CoV-2 transmission rates in schools can alter the progression of the pandemic.

There exists a gap in the implementation of systematic and widespread surveillance testing. As a result, detection between schools and the community is complex. Additionally, unchecked transmission enhances viral mutations and the emergence of newer variants of concern, which can evade vaccine- and infection-acquired immunity and may even prove more virulent.

In order to control the spread of SARS-CoV-2 in schools, sanitization and protective guidelines, as well as air filtration, need to be implemented.

Study: The role of schools in driving SARS-CoV-2 transmission: Not just an open-and-shut case. Image Credit:  / BELL KA PANG Shutterstock

The study

A new research paper published in the journal Cell Reports Medicine elaborated on the limitations of current evidence on school-based transmission, informed about such alterations in the course of COVID-19, and discussed strategies to facilitate in-school learning for children while ensuring their safety and also of the staff and the surrounding communities.

Biases and probable impacts of SARS-CoV-2 infection in school-going children and the increased transmission in school settings

Schools contribute to the COVID-19 burden in communities

In the United States, school-going children, school staff, and first-degree contacts of people regularly visiting schools constitute about half the population. In places where schools were open, a higher number of people reported COVID-19-like symptoms. Further, the rates of infection were higher in regions where schools were reopened without adequate measures to mitigate the indoor spread of the virus.

School reopenings increase the risk of superspreader events. However, proper mitigation strategies and multiple layered interventions, such as face masks, strict hygiene practices, and clear ventilation guidelines, can help avoid this.

For safe reopenings of schools

Limit transmission

By reducing airborne and aerosol transmission and improving air quality, indoor air contamination and infection can be effectively reduced. Adequate ventilation is crucial for decreasing viral load. For this, high-quality filtration equipment with a MERV >9 (minimum efficiency reporting value) can be employed to remove particles 3 microns in diameter or smaller.

Ionizers can also be helpful as they purify the air by generating negatively charged ions which aid in precipitating the aerosolized particles. It is imperative that schools monitor air quality.

Well-fitting masks provide an additional layer of protection. Students and school staff should wear high-quality masks at all times.

Preventing infected individuals from going to schools

Symptomatic and asymptomatic infections can be identified through surveillance testing. A quick turnaround coupled with vigorous contact tracing and isolation protocols has proven highly effective at the university level.

Quarantine and isolation guidelines must also be updated to prevent the spread of illnesses within schools. Furthermore, children who do better with remote learning, as well as those with a high likelihood of infection, should be offered the option of continuing to learn remotely. This reduces the number of asymptomatic and symptomatic individuals in schools

Community support

Limiting community transmission is a crucial step in establishing safe reopenings and the operation of schools. In the scenario of a heightened community burden of infection, schools should consider reinstating remote learning.

Eradicating inefficient measures

Many mitigation measures have proven useless, and removing them will increase efficiency and compliance. These are – temperature checks, repeated surface cleaning, and plexiglass barriers. Unfortunately, these measures contribute to building a "hygiene theater," imparting a false impression of safety. In addition, these practices lead to "pandemic fatigue" – declining trust in pandemic mitigations.

Owing to the waning vaccine-acquired immunity with time and as newer viral variants continue to emerge, complete dependence on vaccines is barely a way to limit transmission. Wearing correctly-fitted N95 masks is an effective and reliable way to prevent transmissions in schools.

A model-based approach should be used to monitor mitigation strategies. The arsenal for combating SARS-CoV-2 transmission in the setting of waning acquired immunity and newer emerging variants of concern must be science-backed. It is critical for the governing authorities to constantly update the preventive and eradication measures to match the viral evolution and control transmission and infection rates.

Being able to cope with the virus does not mean to permit rampant viral growth. Achieving an end to the crisis phase of the current COVID-19 pandemic is a goal we all share, but achieving it will require hard work on our part since, at present, the disease is nowhere near endemic status. First and foremost, it is essential to limit disease spread inside schools. It is encouraging that we are close to limiting the spread of disease within schools through science-driven interventions. Keeping schools open without accelerating the pandemic should be a priority for public health. In short, the aim is to support in-school learning without causing another public health crisis.