Beata Nowok , University of Edinburgh
Chris Dibben, University of Edinburgh
The first year of life is associated with dynamic developmental changes in the immune system. The newborn is equipped primarily with passive protection received from its mother in the form of antibodies. Between 3 and 6 months infants face a period of increased susceptibility to infections as a result of the maternal transplacental defence fading away and the babies’ antibodies just starting to be produced. Later on babies must rely on its own immature immune system supported to some extent by antibodies from breast milk. We use Scottish infant mortality data from the beginning of the twentieth century, when infant mortality was high and post-neonatal deaths constituted the majority of infant deaths, to explore differences by age in months (or days). We find some evidence for distinctive stages in early life with 2nd/3rd month and 6th month being the most pronounced markers. The decline in infant mortality rate in the analysed period was driven mostly by decreasing number of deaths of those older than 6 months. Mortality rates of younger infants (late neonatal and post-neonatal until 6th month) stagnated or in some places, e.g. Glasgow and Edinburgh, even increased in the thirties. Analysis of seasonality reveals existence of distinctive profiles for infants older than 2 months and younger than 6 months until around 1920. They had an evident summer hump which was not present in other age groups. Infants who survived at least 6 months were more vulnerable during spring and winter time and they were at very high risk of dying during flu outbreaks.
Presented in Session 24. Health and Well-being of the Youngest: Infant and Child Mortality