From privies to disease: Parasites and pollen from 19th century Québec City

This project combines the analysis of parasites and pollen remains from a wealthy 19th century household in Québec City, Canada to examine health as it intersects with ecological and cultural factors of disease transmission in changing urban environments.

Nineteen sediment samples from two privy structures from a 19th century wealthy household in Québec City, Canada.

The parasite analysis was conducted by examining the sediment through acid digestion, deflocculation and micro-sieving, and observed under a brightfield microscope. Pollen analysis followed the same method, but the sediments were further treated with acetolysis before microscopic observation.

The samples tested positive for the parasites Trichuris trichiura, Ascaris lumbricoides and capillariids. The pollen spectra showed a mixed diet based on species of cereals and other starchy foods, fruits, and green leaves, as well as condiments and potential medicinal ingredients (Myrtaceae).

The household members were infected with intestinal parasites spread through contact with fecal contaminated soils, suggesting deficient sanitation and hygiene. The pollen grains recovered evidence of a staple diet and medicinal remedies.

This project highlights the benefits of using multiple lines of evidence to understand health in the past. Insight into how urbanization and poor sanitation can create environments conducive to parasite infection is gained and expands our knowledge of disease transmission and the synergies between environment and disease.

The analysis of privy structures offers an interpretation at the community level, masking individual idiosyncrasies.

Similar studies on other contemporaneous sites across the city are needed to better comprehend the link between pathogen transmission, disease intensity and socioenvironmental factors.