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Rapid onset of functional tic-like behaviors among adolescent girls-Minnesota, September-November 2021
Melanie J Firestone1,2, Stacy Holzbauer2,3, Christine Conelea4
1Epidemic Intelligence Service, Centers for Disease Control and Prevention (CDC), Atlanta, GA, United States.
Background:
On October 15, 2021, the Minnesota Department of Health began investigating a school cluster of students experiencing tic-like behaviors thought to be related to recent COVID-19. The objective of this report is to describe the investigation, key findings, and public health recommendations.
Methods:
Affected students and proxies were interviewed with a standardized questionnaire including validated depression and anxiety screens.
Results:
Eight students had tic-like behaviors lasting >24 h after initial report with onset during September 26-October 30, 2021. All eight students were females aged 15-17 years. All students either had a history of depression or anxiety or scored as having more than minimal anxiety or depression on validated screens. Four students previously had confirmed COVID-19: the interval between prior COVID-19 and tic symptom onset varied from more than a year prior to tic symptom onset to at the time of tic symptom onset.
Conclusion:
The onset of tic-like behaviors at one school in Minnesota appeared to be related more to underlying mental health conditions than recent COVID-19. These findings highlight the need to better understand functional tic-like behaviors and adolescent mental health.
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