title: Early exposure to pets: good or bad?
abstract: Although pet exposure is known to trigger or worsen allergy symptoms and asthma in patients sensitized to pets, data from recent years has shown that pet exposure in early childhood may actually prevent the development of allergic sensitization and allergic diseases including allergic rhinitis, asthma, and atopic dermatitis. The concept of a protective pet effect remains controversial because these findings have not been duplicated in all studies. Moreover, some studies suggest that pet exposure promotes allergic disease. The protective pet effect may be influenced by multiple factors including type of pet; timing, duration, and intensity of exposure; and genetic factors. The mechanisms behind the protective pet effect remain under investigation but may include alterations in immune development, pet-specific tolerance, and exposure to innate immune stimuli.
authors: University of Wisconsin Hospital and Clinics, 600 Highland Avenue, K4/918, CSC Box 9988, Madison, WI 53792, USA.
authors: Jeremy D
authors: JD
authors: Bufford
authors: James E
authors: JE
authors: Gern
mesh_terms: D000818:Animals; D000829:Animals, Domestic / Q000276:immunology*; D002648:Child; D005260:Female; D006801:Humans; D006967:Hypersensitivity / Q000276:immunology*; D007113:Immunity, Innate; D008297:Male
references: J Allergy Clin Immunol. 2006 Dec;118(6):1271-8
references: 17157656
references: Allergy. 2005 May;60(5):619-25
references: 15813806
references: Allergy. 2003 Sep;58(9):939-44
references: 12911425
references: Am J Respir Crit Care Med. 2002 Oct 1;166(7):939-44
references: 12359650
references: BMJ. 2004 May 22;328(7450):1223
references: 15121716
references: J Allergy Clin Immunol. 1999 Mar;103(3 Pt 1):415-20
references: 10069874
references: Pediatr Allergy Immunol. 2004 Aug;15(4):316-22
references: 15305940
references: Clin Exp Allergy. 2003 Sep;33(9):1190-7
references: 12956738
references: Ann Epidemiol. 2004 Sep;14(8):543-50
references: 15350953
references: Clin Exp Allergy. 2003 Dec;33(12):1681-5
references: 14656355
references: J Allergy Clin Immunol. 1999 Nov;104(5):941-7
references: 10550736
references: J Allergy Clin Immunol. 2004 Feb;113(2):307-14
references: 14767447
references: J Allergy Clin Immunol. 2003 Aug;112(2):362-8
references: 12897743
references: Allergy. 2005 Feb;60(2):177-84
references: 15647038
references: Lancet. 2001 Jul 21;358(9277):188-93
references: 11476835
references: Allergy. 2003 Oct;58(10):1033-6
references: 14510722
references: J Allergy Clin Immunol. 2002 Nov;110(5):736-42
references: 12417882
references: Allergy. 2001 Apr;56(4):307-12
references: 11284797
references: J Allergy Clin Immunol. 1999 Oct;104(4 Pt 1):755-62
references: 10518818
references: J Allergy Clin Immunol. 2001 Mar;107(3):455-60
references: 11240945
references: Am J Respir Crit Care Med. 2004 Aug 1;170(3):273-8
references: 15117746
references: Clin Exp Allergy. 1999 May;29(5):611-7
references: 10231320
references: J Allergy Clin Immunol. 1999 Oct;104(4 Pt 1):775-85
references: 10518821
references: J Allergy Clin Immunol. 2001 Nov;108(5):847-54
references: 11692114
references: J Allergy Clin Immunol. 2006 Sep;118(3):691-8
references: 16950289
references: Clin Exp Allergy. 2001 Dec;31(12):1839-45
references: 11737034
references: Pediatrics. 2001 Aug;108(2):E33
references: 11483843
references: N Engl J Med. 2002 Sep 19;347(12):869-77
references: 12239255
references: Pediatrics. 2004 Jul;114(1):13-8
references: 15231902
references: J Allergy Clin Immunol. 2001 May;107(5):790-6
references: 11344344
references: Am J Epidemiol. 2002 Nov 15;156(10):977-83
references: 12419771
references: Allergy. 2003 Nov;58(11):1136-43
references: 14616124
references: J Allergy Clin Immunol. 2005 May;115(5):946-52
references: 15867850
references: Clin Exp Allergy. 2002 Mar;32(3):361-6
references: 11940064
references: Clin Exp Allergy. 1998 Jan;28(1):53-9
references: 9537780
references: Pediatr Allergy Immunol. 2002 Oct;13(5):334-41
references: 12431192
references: J Allergy Clin Immunol. 2001 Oct;108(4):509-15
references: 11590373
references: J Allergy Clin Immunol. 2005 Jul;116(1):223-5
references: 15990800
references: J Allergy Clin Immunol. 2001 Oct;108(4):537-9
references: 11590378
references: Br J Dermatol. 2005 Apr;152(4):742-9
references: 15840107
references: J Allergy Clin Immunol. 1997 Jun;99(6 Pt 1):763-9
references: 9215243
references: Lancet. 2001 Mar 10;357(9258):752-6
references: 11253969
references: Arch Pediatr Adolesc Med. 2004 Oct;158(10):996-1001
references: 15466689
references: Environ Health Perspect. 2006 Dec;114(12):1916-22
references: 17185285
references: Clin Exp Allergy. 1995 Feb;25(2):119-26
references: 7750003
references: J Allergy Clin Immunol. 2003 Aug;112(2):289-300
references: 12897734
references: Allergy. 2005 Jun;60(6):766-73
references: 15876306
references: Pediatr Allergy Immunol. 2002 Dec;13(6):394-401
references: 12485314
references: J Allergy Clin Immunol. 1993 May;91(5):1067-74
references: 8491939
references: Am J Respir Crit Care Med. 2002 Sep 1;166(5):696-702
references: 12204868
references: J Allergy Clin Immunol. 2005 Jan;115(1):74-9
references: 15637550
references: JAMA. 2002 Aug 28;288(8):963-72
references: 12190366
references: Lancet. 2002 Sep 7;360(9335):781-2
references: 12241839
references: Clin Exp Allergy. 1996 Nov;26(11):1246-52
references: 8955573
references: Allergy. 1999 Aug;54(8):843-50
references: 10485388