This study explored whether the yard environment and child hygiene and play behaviours were associated with presence and intensity of Ascaris and hookworm in preschool children and with eggs and larvae in soil. Data were collected using questionnaires, a visual survey of the yard, soil samples and fecal samples collected at baseline and following re-infection. The presence of eggs/larvae in soil was associated negatively with water storage (eggs) but positively with dogs (eggs) and distance from home to latrine (larvae). Baseline and re-infection prevalences were: hookworm (28.0%, 3.4%); Ascaris (16.9%, 9.5%); Trichuris (0.9%, 0.7%). Zero-inflated negative binomial regression models revealed a higher baseline hookworm infection if yards had eggs or larvae, more vegetation or garbage, and if the child played with soil. Baseline Ascaris was associated with dirt floor, dogs, exposed soil in yard, open defecation and with less time playing outdoors, whereas Ascaris re-infection was associated with water storage, vegetation cover and garbage near the home and not playing with animals. Our results show complex interactions between infection, the yard environment and child behaviours, and indicate that transmission would be reduced if latrines were closer to the home, and if open defecation and water spillage were reduced.

Parasite communities were examined in johnny darters (Etheostoma nigrum) collected from five localities in the St. Lawrence River in southwestern Quebec: two reference localities, one polluted locality upstream of the Island of Montreal and downstream of industrial and agricultural activity, and two polluted localities downstream of the Island of Montreal in the plume from the wastewater treatment facility. Twenty-four helminth species were found. Fish from the upstream polluted locality had the highest parasite species richness and total parasite numbers, and fish from the downstream polluted localities the lowest. Nonmetric multivariate analyses were conducted using square-root-transformed Bray-Curtis dissimilarity index. An analysis of similarity, dendrogram of centroids, and a permutational multivariate analysis of variance with contrasts all showed that fish from the reference localities had different parasite community composition than those from the polluted localities, and fish from the upstream polluted locality had different parasite communities than fish from the downstream polluted localities. Differences between reference and polluted localities were mainly due to higher abundances of the brain-encysting trematode, Ornithodiplostomum sp., at the reference localities. Differences between upstream and downstream polluted localities were mainly due to a higher diversity and abundance of trematodes in fish at the upstream locality.

Objective:To determine if constraints on agricultural production were a novel construct in the Panama Food Security Questionnaire (FSQ) and to characterize agricultural and economic determinants of food insecurity during the planting, growing and harvesting time periods in subsistence farming communities.Design:This longitudinal study followed households during land preparation, growing and harvest periods in one agricultural cycle. Agricultural production and economic variables were recorded and the Panama FSQ was administered. Exploratory factor analysis was used to verify construct validity of the FSQ. A food insecurity score (FIS), ranging from 0 to 42, was derived. Multiple regression analyses of FIS were conducted for each agricultural period.Setting:Fifteen rural villages in Panama.Participants:Subsistence farming households (n 237).Results:The FSQ contained four constructs: (i) ability to buy food; (ii) decreased amount/number of meals; (iii) feeling hungry; and (iv) lower agricultural production because of weather or lack of resources. Although most households were mildly food insecure in all time periods, determinants of food insecurity differed in each. Higher FIS was associated during land preparation with less rice and legumes planted and lower asset-based wealth; during growing months with less rice, more maize and pigeon peas planted and not selling produce; and during harvest with less rice planted, fewer chickens and lower income.Conclusions:Constraints on agriculture was a novel construct of the Panama FSQ. Different income-related variables emerged in each agricultural period. Planting staple foods and raising chickens were associated with food security, but some crop choices were associated with food insecurity.

This longitudinal study explored whether aspects of subsistence agriculture were associated with presence and intensity of Ascaris and hookworm in preschool children in rural Panama. Questionnaires were used to collect data on household socio-demographics, child exposure to agriculture and household agricultural practices. Stool samples were collected from children (6 months-5 years) at 3 time points, with albendazole administered after each to clear infections, resulting in 1 baseline and 2 reinfection measures. A novel Agricultural Activity Index (AAI) was developed using principal components analysis to measure the intensity of household agricultural practices. Zero-inflated negative binomial regression models revealed baseline hookworm egg counts were higher if children went to the agricultural plot and if the plot was smaller. Baseline and reinfection Ascaris egg counts were higher if children went to the plot and households had higher AAI, and higher at baseline if the plot was smaller. Caregiver time in the plot was negatively associated with baseline Ascaris egg counts, but positively associated with baseline hookworm and Ascaris reinfection egg counts. Children who spent more time playing around the home were less likely to be infected with Ascaris at baseline. We conclude that preschool child exposure to subsistence agriculture increased Ascaris and hookworm intensity.