Entomologist, Zoologist, Parasitologist, Medical Scientist and Army Medical Officer

Her discovery of the life history of the rat lungworm, which was later named in her honour, was a landmark achievement that contributed to our understanding of parasitic diseases. Her research—recorded in more than eighty papers—has contributed to entomology, veterinary medicine and medical science. 

Born in 1896 in Deception Bay, Josephine completed her schooling at Brisbane Girls Grammar School, before studying a Bachelor of Science at The University of Queensland (UQ) in 1918. For the two years following, while undertaking a Walter and Eliza Hall Fellowship in economic biology, Dr Mackerras co-published research papers with renowned biologist Thomas Johnston. After graduating in 1914, Josephine went on to study Medicine at the University of Sydney and was later awarded a Master of Science degree in 1930. 

In 1924, Josephine met her husband Ian Mackerras while completing her medical training. The couple were united by their shared fascination with science, and their pastimes included boating, fishing and flying. In 1926, Josephine gave birth to their son before returning to work in 1930 at the CSIR (soon renamed CSIRO) as an assistant entomologist alongside her husband Ian. The pair became one of the most distinguished and celebrated scientific duos in Australia. They collaborated in publishing a series of papers on the blood parasites of Australian marine fish, blowfly control in sheep, tick-borne fevers in cattle and other insect-related research. Josephine’s contributions to the field of entomology were widely recognized, and she was appointed as a Junior Research Officer in the division. 

The outbreak of the Second World War in 1939 triggered another important phase in Josephine’s life. Following the disastrous epidemics of malaria during and following the Papuan campaigns of 1942-43, Josephine was appointed Entomologist to the Land Headquarters Medical Research Unit (LHQMRU) Entomology Section. The section bred and maintained a large stock of infected mosquitoes which were used to transmit malaria to volunteers from many Army units—an experimental program which enabled malaria to be controlled in Papua New Guinea and other theatres of war in the South-West Pacific. Josephine’s groundbreaking work in controlling the incidence of infection played a crucial role in maintaining the health of Australian soldiers serving in the Pacific and was an important factor in the Allied victory. Josephine was recommended for a military MBE on three occasions by the DGMS, Major-General S.R. Burston. In his recommendations Burston wrote that ‘few women can have made a greater contribution to the Allied war effort.’ 

Following the war, Josephine continued her research at CSIR laboratories in Brisbane. In 1947, Josephine obtained a position at the newly-founded Queensland Institute of Medical Research (QIMR) as senior parasitologist in 1947 where she conducted research on various parasites and infectious diseases. Among the various projects on which she was engaged, her chief contribution to scientific knowledge came from her study of the parasites of Australian mammals. Her discovery of the life history of the rat lungworm, which was later named Angiostrongylus mackerrasae in her honour, was a landmark achievement that contributed to our understanding of parasitic diseases.  

Both Ian and Josephine retired from the QIMR in 1961 and returned to Canberra, where they settled and remained actively involved in a range of scientific organisations. Josephine was elected a Fellow of the Royal College of Pathologists of Australasia, a Fellow of the Australian Society of Parasitology and was a member of the Royal Society of Queensland. She was awarded the W.B. Clarke Medal of the Royal Society of New South Wales in 1965, and an honorary doctorate in science by The University of Queensland. She served on the Great Barrier Reef Committee, helped to establish the Marine Research Station on Heron Island, and presided over the Queensland Medical Women’s Society and the Women Graduates’ Association.  

Josephine’s portrait by Nora Heysen is held by the Australian War Memorial. She is remembered as a person of great strength of character and her unwavering commitment to scientific inquiry, pioneering research, and tireless advocacy for public health has had enduring impact. Hers is a legacy that continues to inspire future generations of scientists.