Fel d 1 and Can f 1 in settled dust and airborne Fel d 1 in allergen avoidance day-care centres for atopic children in relation to number of pet-owners, ventilation and general cleaning.
BACKGROUND
Special day-care centres for atopic children have been established in Sweden.


OBJECTIVE
To study concentrations of cat (Fel d 1) and dog (Can f 1) allergens in settled dust and airborne cat allergen in day-care centres in relation to pet ownership among children and staff, ventilation and general cleaning.


METHODS
Twelve allergen avoidance day-care centres and 22 conventional day-care centres were included in the study. Settled dust was collected and analysed with ELISA. Airborne cat allergen levels were measured in eight allergen avoidance and seven conventional centres with a personal air sampler and analysed with an amplified ELISA. Air change rate per hour (ACH) was measured. A questionnaire which focused on keeping of cat and dog among staff and children and frequency of general cleaning was used.


RESULTS
In the allergen avoidance day-care centres neither children nor staff reported ownership of cats or dogs, compared with 21/22 of the conventional centres in which children and staff kept furred animals. Fel d 1 and Can f 1 were found in settled dust in all day-care centres. In the allergen avoidance compared with the conventional centres the concentrations of Fel d 1 and Can f 1 were lower, Fel d 1: median 0. 64 microg/g vs 5.45 microg/g and Can f 1: 0.39 microg/g vs 2.51, both P < 0.001, and airborne Fel d 1 was also lower in the allergen avoidance centres compared with the control centres, 1.51 ng/m3 vs 15.8 ng/m3, P = 0.002. A correlation was found between airborne and settled Fel d 1, rs = 0.75, P < 0.001. Furthermore, a correlation was found between increased ACH and decreased levels of Fel d 1 in the air in the day-care centres with no cat-owners, rs = - 0.86, P = 0.007. No relation was found between levels of cat or dog allergen and amount of general cleaning.


CONCLUSIONS
Not keeping pets seems to reduce children's exposure to pet-allergen in their 'working environment'. Additionally, appropriate ventilation seems to reduce Fel d 1 in the air in day-care centres.
Wickman
M
M
Department of Environmental Health, Karolinska Hospital, Stockholm, Sweden.
Egmar
A
A
Emenius
G
G
Almqvist
C
C
Berglind
N
N
Larsson
P
P
Van Hage-Hamsten
M
M
D000393:Air Pollutants / Q000032:analysis; D000485:Allergens / Q000032:analysis*; D000818:Animals; D000829:Animals, Domestic; D052179:Antigens, Plant; D002415:Cats; D002656:Child Day Care Centers; D002675:Child, Preschool; D004285:Dogs; D004391:Dust / Q000032:analysis*; D004780:Environment, Controlled; D006023:Glycoproteins / Q000032:analysis*; D006796:Household Work; D006801:Humans; D006969:Hypersensitivity, Immediate / Q000517:prevention & control; D011863:Radioimmunoassay; D014691:Ventilation
D000393:Air Pollutants; D000485:Allergens; D052179:Antigens, Plant; D004391:Dust; D006023:Glycoproteins; C091462:allergen Can f I; C059296:Fel d 1 protein, Felis domesticus