The Journal of Microbiology, December 2002, p.327-330 Vol. 40, No. 4 Copyright 2002, The Microbiological Society of Korea NOTE Determination of Enteric Bacteria at Microbiologically Risky Points by Multiplex Polymerase Chain Reaction Mahir Gulec*, Bilal Bakir, Recai Ogur, and Omer Faruk Tekbas Department of Public Health, Gülhane Military Medical Academy, Ankara, Turkey (Received August 19, 2002 / Accepted November 14, 2002) The purpose of this research was to test multiplex polymerase chain reaction in investigating the micro- biological quality of the risky surfaces in social living places of a military base where over 15 thousand people live together. In 22 samples of 99, there were no bacteria. Only four of the samples contained Shigella, and one of them contained Salmonella, but 77 of the samples contained thermotolerant coliform organisms. There was no statistically significant difference among the microbiological quality of different sites and different equipment surfaces (p>0.05). Key words: swab, coliform organisms, multiplex polymerase chain reaction, surface contamination Thermotolerant (fecal) coliforms and Escherichia coli are organisms which have been used to investigate the micro- biological quality of water and food sources (Conway, 1998). These organisms could also be used to determine microbiological quality of the surfaces of equipment and living places ( Natsiashvili, 1970; Schreiber, 1971; Slavin, 1973) Studies of the contamination level of the surfaces are generally performed in order to determine efficacy of the cleaners which contain disinfectants or to determine the source of an outbreak. In this kind of study, a swab tech- nique for sampling and total bacterial count for evaluation are commonly used (Spicher and Peters, 1976; Pfeiffer et al., 1978; Keswick et al ., 1983; Scott et al ., 1984; Borneff, 1986; Mafu et al., 1990). The swab method is one of the most common methods used to investigate the contamination level of surfaces (Pfeiffer et al., 1978; Keswick et al., 1983; Mafu et al., 1990). After collection of the samples from investigated surfaces, one must use appropriate media to culture micro- organisms. In order to isolate microorganisms exactly we need more special methods. This isolation process is time consuming. The polymerase chain reaction (PCR) technique has been commonly used to detect microorganisms in micro- biology. Multiplex PCR is a method which you could detect several microorganisms or other nucleic materials by using corresponding primer sets in the same reaction. Especially when used to detect bacteria, the complete pro- cedure could be as short as three or four hours. By using PCR and multiplex PCR, we also could detect “viable but nonculturable (stressed) microorganisms” which can not be isolated by classical culture methods (Roszack and Colwell, 1987). The purpose of the present study was to test multiplex PCR in order to investigate the microbiological quality of the risky surfaces in social living places of a military base where over 15 thousand people live together. In this way we also intended to evaluate hygienic activities performed in a public living place by PCR. Study Sites and Sample Collection Ninety-nine common living places in a military facility were examined in this study. The study type was descrip- tive. Primarily, the surfaces of taps, dining tables, door handles, equipment from kitchens and dining halls and soap and soap dishes were investigated. To collect sam- ples from surfaces, cotton swabs were prepared and ster- ilized in an autoclave (at 120 o C for 30 min). Transport medium was prepared using peptone (Sigma, USA), lac- tose (Sigma, USA) and beef extract powder (Sigma, USA) 10, 10 and 6 grams respectively, in one liter dis- tilled water. The pH was adjusted to 7.4 and sterilized as described above. Samples were taken cotton swabs on tar- get surfaces with an average area of 25 cm 2 (21~30 cm 2 ). The swabs were put into separate transport mediums and transmitted to the PCR Laboratory of the Public Health Department within two hours on ice. Tubes, containing 5 * To whom correspondence should be addressed. (Tel) 90-312-3044663; (Fax) 90-312-3234923 (E-mail) mglec@yahoo.com