SARS-CoV-2 Variant Tracking and Mitigation: Strategies and Results from In-Person Learning at a Midwestern University in the 2020/2021 School Year
Authors: Avendano Carolina , Lilienfeld Aaron , Rulli Liz , Stephens Melissa , Barrios Wendy Alvarez , Sarro Joseph , Pfrender Michael E. , Miranda Marie Lynn 
Published: September 2021

ABSTRACTImportanceThe COVID-19 pandemic led many higher education institutions to close campuses during the 2020-21 academic year. As campuses prepared for a return to in-person education, many institutions were mandating vaccines for students and considering the same for faculty and staff. This paper demonstrates the effectiveness of such a strategy based on evidence from a mid-sized midwestern university.ObjectiveTo determine whether high vaccination coverage can mitigate the spread of SARS-CoV-2, even in the presence of highly-transmissible variants and congregate living.SettingThis study was conducted at a mid-sized midwestern university during the spring 2021 semester.DesignThe university developed a saliva-based surveillance program capable of high-throughput SARS-CoV-2 polymerase chain reaction testing and genomic sequencing with the capacity to deliver results in less than 24 hours. On April 7, 2021, the university announced a vaccine requirement for all students for the fall 2021 semester and announced the same requirement for faculty and staff on May 20, 2021. The university hosted an onsite mass vaccination clinic using the two-dose Pfizer-BioNTech vaccine April 8-15 and April 29 - May 6, 2021. Data from January 6 - May 20, 2021 were analyzed.ParticipantsThis study includes 14,894 individuals from the university population who tested on campus for COVID-19 during the spring 2021 semester.Main Outcomes and MeasuresPositive SARS-CoV-2 diagnosis was confirmed by quantitative reverse transcription–polymerase chain reaction (qRT-PCR) of saliva specimens and variant identity was assessed by qRT-PCR and next-generation sequencing (NGS) of viral genomes.ResultsBetween January and May 2021, the university conducted 196,185 COVID-19 tests and identified 1,603 positives – ∼89% students – with 687 identified via PCR of saliva specimens. The Alpha (B.1.1.7) variant constituted 44% of total positives sequenced. By May 20, 2021, 91% (10,068) of students, 92% (814) of faculty, and 72% (2,081) of staff were vaccinated. The 7-day rolling average of positive cases peaked at 37 cases on February 17 but declined to zero by May 14, 2021. The 7-day moving average of positive cases was inversely associated with the cumulative vaccination rate.Conclusions and RelevanceThis study demonstrates the high effectiveness of robust vaccination programs even in the presence of highly-transmissible variants and congregate living.KEY POINTSQuestionHow is the spread of COVID-19 affected by increasing rates of vaccination?FindingsWe leverage 190,000+ COVID-19 surveillance tests including 1,603 positives for COVID-19 at a mid-sized midwestern university from January 6 – May 20, 2021. Genomic sequencing indicates that the Alpha (B.1.1.7) variant was first identified in early February and became the dominant variant by early March and the only variant resulting in positive cases by April. An increase in vaccination was associated with a dramatic decrease in COVID-19 cases in the campus population.MeaningMass vaccination efforts can effectively control the spread of SARS-CoV-2 even as highly-transmissible variants are introduced.