Socio-economic status can have health effects. A group of researchers led by Katia M. Charland of Children's Hospital Boston, Massachusetts, studied the relative rates of influenza infection in people with varying levels of social and material deprivation. Charland and colleagues defined material deprivation as “lack of access to goods and services”, and social deprivation as “lack of social cohesion and support”.
“Defining subpopulations that initiate and promote influenza epidemics can help to guide the strategic distribution of prevention and control efforts,” Charland explained. Previous research has demonstrated that severe respiratory illness occurs at higher rates in socio-economically deprived groups.
However, these results were based on hospitalization and mortality data. The rates of infection in the community have not been previously studied as a function of socio-economic status.
The data came from Montreal, Quebec, Canada, where 99 percent of the residents have the same health insurance plan provided by the government body Regie de l'assurance maladie du Quebec. The geographical area was divided into 111 neighborhoods. Indices of material and social deprivation from a previous study were used.
The variables for material deprivation were proportion of persons lacking a high school diploma, employment to population ratio, and average income. The variables for social deprivation were the proportion of persons living alone, the proportion of persons separated, divorced, or widowed, and the proportion of single parent families. Influenza infection rates were based on the rates of visits to outpatient clinics and emergency departments.
“There was little evidence of a meaningful linear relationship with material deprivation,” Charland found. A plot of influenza infection rate versus material deprivation for the 111 neighborhoods shows a small difference in infection between the highest and lowest material deprivation rates, but a much larger scatter to the data. Thus, influenza does not discriminate based on material wealth factors.
Surprisingly, social deprivation was associated with less infection.