Background: The psychological impact of the COVID-19 pandemic on doctors is a significant concern. Due to the emergence of a multiple pandemic waves, longitudinal data on the impact of COVID-19 is vital to ensure an adequate psychological response. The primary aim was to assess the prevalence and degree of psychological distress and trauma in Emergency Medicine (EM), Anaesthetics and Intensive Care Medicine (ICM) doctors during the acceleration, peak and deceleration of the COVID-19 first wave. Personal and professional factors associated with psychological distress are also reported. Methods: A prospective online three-part longitudinal survey of frontline doctors across the UK and Ireland, administered at the acceleration, peak and deceleration of the COVID-19 first wave. Primary outcome measures were psychological distress and trauma, measured using the General Health Questionnaire-12 and the Impact of Events-Revised. Findings: Acceleration survey response rate was 15.9% (n=5440), of an estimated 34,188 doctors. Peak and deceleration response rates were 71·6% (n=3896) and 56·6% (n=3079) respectively. Prevalence of psychological distress was 44·7% (n=1334) during the acceleration, 36·9% (n=1098) at peak and 31·5% (n=918) at the deceleration phase. The prevalence of trauma was 23·7% (n=647) at peak and 17·7% (n=484) at deceleration. The prevalence of probable post-traumatic stress disorder was 12·6% (n=343) at peak and 10·1% (n=276) at deceleration. Worry of family infection due to clinical work was most strongly associated with both distress (R2 = 0·06) and trauma (R2 =0·10). Interpretation: Findings reflect a pattern of elevated distress at acceleration and peak, with some natural recovery. It is essential that policymakers seek to prevent future adverse effects through (a)provision of vital equipment to mitigate physical and psychological harm (b)increased awareness and recognition of signs of psychological distress and (c)the development of clear pathways to effective psychological care. Funding: Funding received from the Royal College of Emergency Medicine.Declaration of Interests: Many of the authors have been working as frontline clinicians during the COVID-19 pandemic. They have no competing interests to declare.Ethics Approval Statement: Ethical approval was obtained from the University of Bath (UK) and Children’s Health Ethics Committee (Ireland). Regulatory approval was obtained from the Health Regulation Authority (UK), Health and Care Research Wales. Participants provided electronic informed consent for each survey.