Allergy: the protective role of farm life seems to start from fetal life

Children whose mothers were in contact with farm animals during pregnancy could be protected against allergic diseases, preliminary results suggest the PASTURE study.

The PASTURE project (Protection against Allergy - Study in Rural Environments) is a European study set up to confirm previous data from cross-sectional epidemiological studies suggesting a protective role of a rural environment, especially farms, against allergies and asthma, told Reuters Health Prof. Dominique Angèle Vuitton at the University of Franche-Comté in Besançon, co-coordinator for France with Professor Jean-Charles Dalphin CHU Besançon.

PASTURE is a prospective longitudinal study of 1,000 children who all live in rural areas but with a party at the farm (parents farmers in most cases) and the other in villages or towns. In France, the study was conducted in Franche-Comté, with the help of MSA (MSA), said Prof Vuitton.

The study began with women in the third trimester of pregnancy, included between 2002 and 2004. According to the protocol published in Allergy, parents completed questionnaires about their medical history, lifestyle, nutrition and child, breastfeeding, etc ... Blood tests were conducted with parents and children at birth and at each anniversary. Samples were, moreover, made in the environment to assess potential dust and allergens ...

The study is ongoing, with a mean follow-up of three years so far, with national funds, with the aim of having at least one and up to five years if possible until adolescence for allergic diseases can regress spontaneously or emerge by then, explains the specialist.

Researchers have the first results for cord blood: they tend to confirm the protective effect of farm life and especially that influence begins via the mother during pregnancy. This "immunological modulation arising from pregnancy" could be mainly due to the contact of large farm animals such as cows, horses and pigs, as well as the consumption of raw milk.

Immunological analyzes showed that levels of cytokines IFN-gamma, TNF-alpha and IL-10 secreted in the cord blood are higher for children whose mother lives in the farm for those families living there, suggesting that first developed an immune response that would "most likely" to be protected against allergies, says Dr. Vuitton.

These results should be confirmed by further analysis, including exposure times, and the data collected at one, two and three year follow-up. Analyzes of specific IgE are also provided and may provide interesting elements on allergies to milk protein of cow in particular, as well as the pollen present in the farms.

Analysis of "newspapers Health" weekly reports made by the parents of respiratory and skin symptoms during the first year of the child, as well as diagnostics prick tests to one year in France in particular, will show whether a farm life protects against allergic diseases. Preliminary data tend to confirm previous data suggesting a risk divided by two compared to city life, says Professor Vuitton.

The results of the cytokines measured in cord blood should be the first of PASTURE project to be published before a variety of other data