WWI and domestic work

In 1916, Mackenzie was commissioned in the RAMC and left his father's general practice in Huddersfield.

As part of the RAMC, Mackenzie was posted to Mesopotamia, where he was attached to a hospital in Basra dealing with cases of infectious diseases, including cholera, small pox, typhus and plague. Later in the war, he became Assistant Port Health Officer in Basra, which involved monitoring the health conditions in the port, including treating foot and mouth disease in Indian bulls used to draw the guns.

After the War, Mackenzie left his practice in Huddersfield, and took diplomas in public health and tropical medicine. He held posts in the City Hospital for Infectious Diseases in Newcastle-upon-Tyne and as an assistant to the Tuberculosis Officer.

In 1921 he worked as an Assistant Port Health Officer and Aliens Medical Officer in Liverpool. This involved examining crew members on board to ensure they were free from infectious diseases before landing in the port. As Aliens Medical Officer, Mackenzie worked with the immigration department to ensure that incoming passengers were free of infectious disease.

The papers include personal accounts of Mesopotamia and life in England, including his time in Liverpool, Huddersfield and Newcastle; correspondence relating to Mackenzie's studies and appointment as Assistant Port Medical Officer at Liverpool Port Sanitary Authority.