[Investigation of Coxiella burnetii contamination in commercial milk and PCR method for the detection of C. burnetii in egg].
A total of 244 milk samples collected from supermarkets in Tokyo were examined for contamination with Coxiella burnetii. C. burnetii DNA was detected in 131 (53.7%) of the samples by nested PCR. PCR-positive samples were injected into immunosuppressed A/J strain mice. Of the 22 PCR-positive milk samples tested, none resulted in isolation of C. burnetii from the mice. Heat-treatment was sufficient to inactivate C. burnetii in commercial milk. In addition, a PCR detection method for C. burnetii in chicken egg was developed. Egg yolk was added to an equal volume of 1 mol/L of NaCl phosphate buffer and homogenized for removal of protein and lipid. After centrifugal separation, the supernatant was removed, and template DNA in the precipitate was extracted using SDS, proteinase K and NaI. Using such prepared samples, 3.2 x 10(1) C. burnetii particles in 1 g of egg yolk could be detected by nested PCR. All of 200 chicken egg samples collected from supermarkets in Tokyo were negative for C. burnetii by the nested PCR method.
Hirai
Akihiko
A
Tokyo Metropolitan Institute of Public Health: 3-24-1, Hyakunincho, Shinjuku-ku, Tokyo 169-0073, Japan.
Kaneko
Seiji
S
Nakama
Akiko
A
Ishizaki
Naoto
N
Odagiri
Megumi
M
Kai
Akemi
A
Sadamasu
Kenji
K
Shinkai
Takayuki
T
Yano
Kazuyoshi
K
Morozumi
Satoshi
S
D000818:Animals; D002021:Buffers; D002645:Chickens; D016997:Coxiella burnetii / Q000302:isolation & purification*; D004269:DNA, Bacterial / Q000032:analysis; D004530:Egg Yolk / Q000382:microbiology; D004531:Eggs / Q000382:microbiology*; D005516:Food Microbiology; D006358:Hot Temperature; D051379:Mice; D008892:Milk / Q000382:microbiology*; D010710:Phosphates / Q000494:pharmacology; D016133:Polymerase Chain Reaction / Q000379:methods*; D014041:Tokyo
D002021:Buffers; D004269:DNA, Bacterial; D010710:Phosphates; C018279:sodium phosphate