Adaptive immune responses to SARS-CoV-2 persist in the pharyngeal lymphoid tissue of children.

Most studies of adaptive immunity to SARS-CoV-2 infection focus on peripheral blood, which may not fully reflect immune responses at the site of infection. Using samples from 110 children undergoing tonsillectomy and adenoidectomy during the COVID-19 pandemic, we identified 24 samples with evidence of previous SARS-CoV-2 infection, including neutralizing antibodies in serum and SARS-CoV-2-specific germinal center and memory B cells in the tonsils and adenoids. Single-cell B cell receptor (BCR) sequencing indicated virus-specific BCRs were class-switched and somatically hypermutated, with overlapping clones in the two tissues. Expanded T cell clonotypes were found in tonsils, adenoids and blood post-COVID-19, some with CDR3 sequences identical to previously reported SARS-CoV-2-reactive T cell receptors (TCRs). Pharyngeal tissues from COVID-19-convalescent children showed persistent expansion of germinal center and antiviral lymphocyte populations associated with interferon (IFN)-γ-type responses, particularly in the adenoids, and viral RNA in both tissues. Our results provide evidence for persistent tissue-specific immunity to SARS-CoV-2 in the upper respiratory tract of children after infection.

Examining multi-level immune response to determine prevalence of COVID-19 in pediatric tonsillectomy.

OBJECTIVE: To determine the prevalence of COVID-19 in a cohort of children undergoing tonsillectomy through assessment of B cell immune responses to SARS-CoV-2 in both peripheral blood and tonsil tissue. METHODS: In this cohort study at a tertiary pediatric hospital (Children's National Hospital) in Washington, DC, we recruited 100 children undergoing tonsillectomy from late September 2020 to January 2021. Serum, peripheral blood cells, and tonsil tissue were collected and examined for immune reactivity to SARS-CoV-2. Parent-reported clinical histories were compared to antibody and B-cell responses. RESULTS: Among 100 children undergoing tonsillectomy, 19% had evidence of immune responses to SARS-CoV-2 (CoV2+), indicating prior COVID-19. In all seropositive participants, we detected SARS-CoV-2 specific B cells in both peripheral blood mononuclear cells and tonsils, providing evidence for tissue-specific immunity in these children. Of the 19, 63% reported no known history of COVID-19, and an additional 3 were asymptomatic or unaware of an acute infection when detected on pre-surgery screen. Hispanic children represented 74% of CoV2+ subjects compared to 37% of the full cohort. 100% of CoV2+ children lived in a zip code with poverty level >10%. CONCLUSIONS: Nearly one-fifth of children undergoing tonsillectomy at an urban U.S. hospital had evidence of prior COVID-19 during the early pandemic, with the majority unaware of prior infection. Our results underscore the ethnic and socio-economic disparities of COVID-19. We found concordant evidence of humoral immune responses in children in both blood and tonsil tissue, providing evidence of local immune responses in the upper respiratory tract. LEVEL OF EVIDENCE: 3 Laryngoscope, 2022.

Impact of the novel coronavirus on surgical practices at a tertiary pediatric hospital: A 3 year cross-sectional study.

OBJECTIVE: The novel coronavirus (COVID-19) forced unprecedented changes in pediatric otolaryngology workflow in the early pandemic, particularly due to the postponement of elective procedures. In turn, this has impacted timely treatment of patients and ability to train residents and fellows. The objective is to characterize how surgical practices in pediatric otolaryngology have been impacted by the pandemic through a cross sectional analysis over three years. METHODS: This cross-sectional study focuses on patients who underwent surgical procedures within the department of otolaryngology at a single tertiary pediatric hospital. Descriptive statistical analysis was used to compare subsets of patients from pre-pandemic in 2019, early-pandemic in 2020, and late-pandemic in 2021. RESULTS: Operative volume decreased by 87.57% in the early pandemic and 36.86% in the late pandemic. In the early pandemic, the greatest decreases were seen in airway reconstruction (100%), adenotonsillectomy (96.4%), adenoidectomy (94.7%), myringotomy with tympanostomy tube insertion (94.6%), frenulectomy (94.1%), and sinonasal procedures (93.3%), while in the late-pandemic adenotonsillectomy (42.4%) and myringotomy with tympanostomy tube insertion (70.1%) remained reduced when compared to pre-pandemic volume. Increased average case lengths in the early-pandemic (78.28 ± 51.95 min) and late-pandemic (71.91 ± 70.76 min) were observed when compared to pre-pandemic (52.26 ± 39.20 min) (p < 0.001). An increased proportion of multidisciplinary cases were completed in 2020 and 2021 (p < 0.001). In the 2020, 25% of cases were completed without trainee involvement. There was an overall decrease in case numbers for trainees and increase in cases without their involvement when compared to 2019 and 2021. CONCLUSION: The COVID-19 pandemic resulted in a decrease in pediatric otolaryngology surgical procedures, particularly at the onset of the pandemic. While surgical trainees saw a dramatic reduction in case numbers early on, one year into the pandemic case volume is increasing and trending to pre-pandemic numbers. More complex cases, as represented by patients requiring longer operative times, inpatient status, and more frequently multidisciplinary care, were seen in the early pandemic, while drastic reductions were seen in routine outpatient procedures.