"Data from church records for Okak, Hebron, and Brevig also supported the historical anecdotes about the high mortality in these isolated communities," said Mamelund.
The study also shows that it was mainly people belonging to indigenous populations who died in the worst affected areas. Findings suggest, that to a greater extent, the geographically isolated indigenous groups had risk factors associated with influenza, such as co-morbidities e.g. pulmonary tuberculosis, cramped living conditions and poverty compared to Caucasian populations living in cities and countries with a high degree of urbanisation in the West. In addition, loss of caregivers due to high mortality was an indirect cause of many fatalities. Genetic explanations may also have played a role, says Mamelund.
The study is published in the latest issue of the Epidemics journal, and is based on quantitative data from archives and church records and ethnographic data from Scandinavia, North America and Oceania.
What conclusions can be drawn from this study?
"Firstly, the new research shows that it was only in cities and countries in the West that people older than 65 years had lower than expected mortality. In very isolated indigenous communities, mortality was very high for all adults over 30 years of age, and higher than during seasonal outbreaks of influenza in the years before 1918.
"Secondly, we conclude that without adequate immunological protection for large parts of the world's population, Spanish flu would probably have claimed many more lives than the most widely quoted estimate of 50-100 million dead.
|Contact: Julie Johansen|
Norwegian Institute of Public Health