John Morton Sim Coutts, medical practitioner, qualified as a member of the Royal College of Surgeons (MRCS) of England and a liceniate of the Royal College of Physicians (LRCP) of London in 1897, and as Doctor of Medicine (MD) at the University of London in 1899. He also obtained the Diploma in Public Health from the University of Cambridge. In August 1903 he was appointed as senior assistant to Dr Alexander Edington* at the Colonial Bacteriological Institute in Grahamstown, where research was conducted on animal diseases. Edington and Coutts reported progress in the Report of the Director of the Government Bacteriological Institute, on their investigation of Trypanosomiasis (1903, Appendix F), 'Redwater or Texas Fever' (June 1904, Appendix E), and 'On a new disease occurring among rats' (June 1904, Appendix F). Coutts also published a paper on 'Heartwater and horse-sickness: A new protective inoculation against horse-sickness' (Journal of Comparative Pathology and Therapeutics, 1905) in support of Edington's work on these diseases and, as co-author with Edington, 'A note on a recent epidemic of trypanosomiasis at Mauritius' (The Lancet, 1907).
Coutts probably left the institute in 1905, the year that Edington resigned, for he was living in London by 1906. Later he returned to South Africa, was registered as a medical practitioner in April 1913, and settled at Britstown in the Karoo. He became a member of the South African Association for the Advancement of Science in 1904, and by 1918 was a life member.