The New Zealand military death toll from the 1918-19 influenza pandemic was much higher than earlier estimates, a new study indicates after researchers gained access to records not previously included.
The study, by Jennifer Summers of Otago University and colleagues, adds 258 "military deaths" after an analysis of individual soldiers' files and medical records held in Britain.
This has produced a new estimate of 930 deaths in the New Zealand Expeditionary Force after also including deaths of men who were recently discharged from the armed forces.
"This brings the grand total of New Zealanders who died in the 1918 pandemic to 8831," the researchers say in today's New Zealand Medical Journal.
The death rate in the Expeditionary Force was 8.8 per 1000, compared with 5.8 per 1000 among the national non-Maori population and 42 per 1000 among Maori.
The researchers also found higher influenza death rates in the military among:
* New recruits, compared with seasoned soldiers
* Soldiers from a rural background, compared with those from towns and cities
* Maori soldiers, compared with Europeans
The common factor is thought to have been less exposure among new recruits and rural people (including Maori) to influenza and other respiratory bugs, although Maori would have had the additional risk factor of lower socio-economic background.
"Some commentators have suggested that newly recruited soldiers lacked immunity due to lack of exposure to influenza infections earlier in 1918."
The researchers noted in the journal that previous studies had found that living in a rural area factor was protective among civilians against the 1918/19 pandemic in New Zealand, Australia and the United States.
"[That] ... may have been due to social-distancing during the pandemic - which would not be relevant in crowded military populations during World War I."
One of the researchers, Associate Professor Nick Wilson, said one lesson to be learnt from studying military death rates and patterns from the 1918/19 pandemic was the importance of preventing large gatherings of people.
"At the time the military authorities, although the pandemic was obviously occurring, kept allowing people into military camps and not, effectively, closing them off. That allowed the pandemic to get into the camps and dramatically increased the death rate.
"If they had closed them off in a quarantine-type situation, they could have avoided a lot of unnecessary deaths.
"And they were so busy organising armistice celebrations, people were moving all around the country, including troops to go in processions, and that just contributed further to the pandemic spread."
The new estimates of deaths from the influenza pandemic in 1918/19:
* 930 - New Zealand Expeditionary Force
* 8831 - All New Zealand