Human Salmonella infections linked to contaminated dry dog and cat food, 2006-2008.
OBJECTIVE
Human Salmonella infections associated with dry pet food have not been previously reported. We investigated such an outbreak of Salmonella Schwarzengrund and primarily affecting young children.


METHODS
Two multistate case-control studies were conducted to determine the source and mode of infections among case-patients with the outbreak strain. Study 1 evaluated household exposures to animals and pet foods, and study 2 examined risk factors for transmission among infant case-patients. Environmental investigations were conducted.


RESULTS
Seventy-nine case-patients in 21 states were identified; 48% were children aged 2 years or younger. Case-households were significantly more likely than control households to report dog contact (matched odds ratio [mOR]: 3.6) and to have recently purchased manufacturer X brands of dry pet food (mOR: 6.9). Illness among infant case-patients was significantly associated with feeding pets in the kitchen (OR: 4.4). The outbreak strain was isolated from opened bags of dry dog food produced at plant X, fecal specimens from dogs that ate manufacturer X dry dog food, and an environmental sample and unopened bags of dog and cat foods from plant X. More than 23 000 tons of pet foods were recalled. After additional outbreak-linked illnesses were identified during 2008, the company recalled 105 brands of dry pet food and permanently closed plant X.


CONCLUSIONS
Dry dog and cat foods manufactured at plant X were linked to human illness for a 3-year period. This outbreak highlights the importance of proper handling and storage of pet foods in the home to prevent human illness, especially among young children.
Behravesh
Casey Barton
CB
National Center for Zoonotic, Vectorborne, and Enteric Diseases, Division of Foodborne, Bacterial, and Mycotic Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia 30333, USA. cbartonbehravesh@cdc.gov
Ferraro
Aimee
A
Deasy
Marshall
M
Dato
Virginia
V
Moll
Mària
M
Sandt
Carol
C
Rea
Nancy K
NK
Rickert
Regan
R
Marriott
Chandra
C
Warren
Kimberly
K
Urdaneta
Veronica
V
Salehi
Ellen
E
Villamil
Elizabeth
E
Ayers
Tracy
T
Hoekstra
R M
RM
Austin
Jana L
JL
Ostroff
Stephen
S
Williams
Ian T
IT
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000821:Animal Feed / Q000382:microbiology*; D000818:Animals; D016022:Case-Control Studies; D002415:Cats; D002648:Child; D002675:Child, Preschool; D004196:Disease Outbreaks; D004285:Dogs; D005260:Female; D005516:Food Microbiology; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D012475:Salmonella / Q000302:isolation & purification*; D012480:Salmonella Infections / Q000453:epidemiology* / Q000635:transmission*; D013997:Time Factors; D014481:United States / Q000453:epidemiology; D055815:Young Adult