The overall objective of this mixed-method digital-based observational study was to determine the mental health impact among CTU staff working during the COVID-19 pandemic. The Qualtrics Core XM platform was used to deploy the questionnaire where a quantitative analysis was conducted. The qualitative part of the study used the Microsoft Teams digital application to complete the interviews. Various validated mental health assessments were administered: Vancouver Index of Acculturation (VIA), Hospital Anxiety and Depression Scale (HADS), Insomnia Severity Index (ISI), Pandemic Stress Index (PSI), Burnout Assessment Tool-12 (BAT-12), General Self Efficacy Scale (GSE) and The Everyday Discrimination Scale (EDS). A total of 485 participants took part, of which 73.4% were female and 70.1% of the sample were white British. A high prevalence of anxiety, exhaustion and depression were identified across all participants. A significant mental health impact was identified among the CTU workforce where wellbeing was compromised during the course of the COVID-19 pandemic.