Author/Authors :
Mortazavi، S M J نويسنده Ionizing and Non-ionizing Radiation Protection Research Center (INIRPRC), Shiraz University of Medical Sciences, Shiraz, Iran , , Moradi، M نويسنده Department of Microbiology, School of Medicine, Kerman University of Medical Sciences, Kerman, Iran , , MANSOURI، SH. نويسنده , , Nouri، F نويسنده Pharmaceutical Sciences Research Center, School of Pharmacy, Shiraz University of Medical Science, Shiraz, Iran , , Mortazavi، S A R نويسنده Medical Student, Student Research Committee, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran , , Bahmanzadegan، F نويسنده Medical Student, Student Research Committee, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran ,
Abstract :
Background: Drug resistance is widely believed to be an increasingly serious
threat to global public health. We have previously reported that short term exposure of
microorganisms to diagnostic ultrasound waves could signifcantly alter their sensitivity to antibiotics. In our previous studies, Klebsiella pneumoniae showed major differences in the sensitivity to antibiotics in exposed and non-exposed samples. This study
was aimed at investigating the alteration of antibiotic resistance of Klebsiella pneumonia, after exposure to Wi-Fi 2.4 GHz electromagnetic radiofrequency radiation.
Materials and Methods: In this in vitro study, three replicate agar plates were
used for each test. The antibiotic susceptibility test was carried out using disc diffusion
method on Mueller Hinton agar plates and the inhibition zones in both control and
exposed groups were measured. A common Wi-Fi router was used in this study as the
radiofrequency exposure source. Irradiated samples were exposed to Wi-Fi radiofrequency radiation for 3, 4.5 and 8 hours.
Results: Statistically signifcant variations of sensitivity to antibiotics were found
for all studied antibiotics after 4.5 hours of RF exposure, compared to non-exposed
bacteria. Interestingly, the mean diameters of the inhibition zones after 3 hours of exposure were less than those exposed for 4.5 hours. Following this rise in the sensitivity
to antibiotics, a fall was observed in the bacteria exposed for 8 hours for all studied
antibiotics.
Conclusion: The fndings of this study show a statistically signifcant rise in the
sensitivity of Klebsiella pneumoniae to different antibiotics after 4.5 hours of exposure
to 2.4 GHz Wi-Fi radiation, followed by a fall after 8 hours of exposure. These observations can be interpreted by the concept of non-linearity in the responses of Klebsiella
pneumoniae to different antibiotics after exposure to electromagnetic radiofrequency
radiation. As in this study a minimum level of effect was needed for the induction of
adaptive response, these results also confrm the validity of the so-called “window
theory”.