BackgroundThe first case of COVID-19 in Nigeria was reported on February 27, 2020, and over time, spread across the country leading to many healthcare worker infections. The risk of transmission of COVID-19 within healthcare facilities makes it necessary to establish infection prevention and control measures. The World Health Organisation supported the Nigeria Centre for Disease Control to conduct a train-the-trainers workshop on infection prevention and control for key healthcare workers across Nigeria. Aim/ObjectivesThis study aims to describe the process and results of train-the-trainers as an intervention for national capacity building in infection prevention and control for COVID-19 among healthcare workers in Nigeria. MethodsEight-hour sessions were held over three days with face-to-face instruction and practical hands-on experience in April 2020. A total of 61 healthcare workers participated across the six geographic zones of Nigeria: North Central, North East, North West, South West, South East, and South South. The training included slide presentations, case-based scenarios, and practical hands-on sessions with plenary discussions. Pre- and post-test assessments were used to evaluate knowledge of COVID-19, triage, and infection prevention and control among healthcare workers. Finding/Results69 % (42) of the participants were male 31 % (19) were female, and the majority (67 %) were medical doctors. Others attending were nurses or health administrators. Of the 70 % (26) of the states with existing infection prevention and control structures within the COVID emergency response, only 40 % were functional. The average percentage of pre-test and post-test scores were 60.8 ± 13.4 and 67.8 ± 9 0.3 respectively, showing a statistically significant difference (p > 0.001) in trainee knowledge. Additionally, 70 % of participants evaluated the training workshop as “satisfactory” or higher in training format, relevance for daily clinical work, active participation, learning new concepts, and logistics. ConclusionNationwide infection prevention and control training is feasible during a national health crisis. Infection prevention and control is cardinal in the containment of epidemic-prone diseases like COVID-19 and is invaluable in the prevention of healthcare-associated infections in healthcare settings.