Current Microbiology

, Volume 75, Issue 3, pp 336–342 | Cite as

Microbial Contamination of Smartphone Touchscreens of Italian University Students

  • Silvia Di Lodovico
  • Angela Del Vecchio
  • Valentina Cataldi
  • Emanuela Di Campli
  • Soraya Di Bartolomeo
  • Luigina Cellini
  • Mara Di Giulio
Article

Abstract

In this study, the microbial contamination of smartphones from Italian University students was analyzed. A total of 100 smartphones classified as low, medium, and high emission were examined. Bacteria were isolated on elective and selective media and identified by biochemical tests. The mean values of cfu/cm2 were 0.79 ± 0.01; in particular, a mean of 1.21 ± 0.12, 0.77 ± 0.1 and 0.40 ± 0.10 cfu/cm2 was present on smartphones at low, medium, and high emission, respectively. The vast majority of identified microorganisms came from human skin, mainly Staphylococci, together with Gram-negative and positive bacilli and yeasts. Moreover, the main isolated species and their mixture were exposed for 3 h to turned on and off smartphones to evaluate the effect of the electromagnetic wave emission on the bacterial cultivability, viability, morphology, and genotypic profile in respect to the unexposed broth cultures. A reduction rate of bacterial growth of 79 and 46% was observed in Staphylococcus aureus and Staphylococcus epidermidis broth cultures, respectively, in the presence of turned on smartphone. No differences in viability were observed in all detected conditions. Small colony variants and some differences in DNA fingerprinting were detected on bacteria when the smartphones were turned on in respect to the other conditions. The colonization of smartphones was limited to human skin microorganisms that can acquire phenotype and genotypic modifications when exposed to microwave emissions.

Notes

Acknowledgements

We thank Prof. Rossella Grande for her contribution in the collection of the data from the Microbiology Teaching Laboratory and all students of the Microbiology Teaching Laboratory of the Department of Pharmacy of University “G. d’Annunzio” Chieti-Pescara A.A. 2015/2016 who participated in this study.

Compliance with Ethical Standards

Conflict of interest

The authors declare that they have no conflict of interest.

Ethical Approval

All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards.

Informed Consent

Informed consent was obtained from all individual participants included in the study.

References

  1. 1.
    Akinyemi KO, Atapu AD, Adetona OO, Coker AO (2009) The potential role of mobile phones in the spread of bacterial infections. J Infect Dev Ctries 3:628–632CrossRefPubMedGoogle Scholar
  2. 2.
    Al-Abdalall AHA (2010) Isolation and identification of microbes associated with mobile phones in Dammam in eastern Saudi Arabia. J Family Community Med 17:11–14CrossRefPubMedPubMedCentralGoogle Scholar
  3. 3.
    Bhoonderowa A, Gookool S, Biranjia-Hurdoyal SD (2014) The importance of mobile phones in the possible transmission of bacterial infections in the community. J Community Health 39:965–967.  https://doi.org/10.1007/s10900-014-9838-6 CrossRefPubMedGoogle Scholar
  4. 4.
    Cellini L, Grande R, Di Campli E, Di Bartolomeo S, Di Giulio M, Robuffo I, Trubiani O et al (2008) Bacterial response to the exposure of 50 Hz electromagnetic fields. Bioelectromagnetics 29:302–311CrossRefPubMedGoogle Scholar
  5. 5.
    Cellini L, Grande R, Di Campli E, Di Bartolomeo S, Capodicasa S, Marzio L (2006) Analysis of genetic variability, antimicrobial susceptibility and virulence markers in Helicobacter pylori identified in Central Italy. Scand J Gastroenterol 41:280–287CrossRefPubMedGoogle Scholar
  6. 6.
    Di Giulio M, D’Ercole S, Zara S, Cataldi A, Cellini L (2012) Streptococcus mitis/human gingival fibroblasts co-culture: the best natural association in answer to the 2-hydroxyethyl methacrylate release. APMIS 120:139–146.  https://doi.org/10.1111/j.1600-0463.2011.02828 CrossRefPubMedPubMedCentralGoogle Scholar
  7. 7.
    Egert M, Späth K, Weik K, Kunzelmann H, Horn C, Kohl M, Blessing F (2015) Bacteria on smartphone touchscreens in a German university setting and evaluation of two popular cleaning methods using commercially available cleaning products. Folia Microbiol 60:159–164.  https://doi.org/10.1007/s12223-014-0350-2 CrossRefGoogle Scholar
  8. 8.
    Gerner-Smidt P, Graves LM, Hunter S, Swaminathan B (1998) Computerized analysis of restriction fragment length polymorphism patterns: comparative evaluation of two commercial software packages. J Clin Microbiol 36:1318–1323Google Scholar
  9. 9.
    Hammon M, Kunz B, Dinzl V, Kammerer FJ, Schwab SA, Bogdan C, Uder M et al (2014) Practicability of hygienic wrapping of touchscreen operated mobile devices in a clinical setting. PLoS ONE 9:e106445.  https://doi.org/10.1371/journal.pone.0106445 CrossRefPubMedPubMedCentralGoogle Scholar
  10. 10.
    Jayalakshmi J, Appalaraju B, Usha S (2008) Cellphones as reservoirs of nosocomial pathogens. J Assoc Physicians India 56:388–389PubMedGoogle Scholar
  11. 11.
    Loyola S, Gutierrez LR, Horna G, Petersen K, Agapito J, Osada J, Rios P et al (2016) Extended-spectrum β-lactamase—producing Enterobacteriaceae in cell phones of health care workers from Peruvian pediatric and neonatal intensive care units. Am J Infect Control 44:910–916.  https://doi.org/10.1016/j.ajic.2016.02.020 CrossRefPubMedPubMedCentralGoogle Scholar
  12. 12.
    Masika MM, Omondi GB, Natembeya DS, Mugane EM, Bosire KO, Kibwage IO (2015) Use of mobile learning technology among final year medical students in Kenya. Pan Afr Med J 21:127.  https://doi.org/10.11604/pamj.2015.21.127.6185 CrossRefPubMedPubMedCentralGoogle Scholar
  13. 13.
    McIntosh RL, Iskra S, McKenzie RJ, Chambers J, Metzenthen B, Anderson V (2008) Assessment of SAR and thermal changes near a cochlear implant system for mobile phone type exposures. Bioelectromagnetics 29(1):71–80CrossRefPubMedGoogle Scholar
  14. 14.
    Meadow JF, Altrichter AE, Green JL (2014) Mobile phones carry the personal microbiome of their owners. PeerJ 2:447.  https://doi.org/10.7717/peerj.447 CrossRefGoogle Scholar
  15. 15.
    Melendez JH, Santaus TM, Brinsley G, Kiang D, Mali B, Hardick J, Gaydos CA, Geddes CD (2016) Microwaves-accelerated method for ultra-rapid extraction of Neisseria gonorrhoeae DNA for downstream detection. Anal Biochem 510:33–40.  https://doi.org/10.1016/j.ab.2016.06.017 CrossRefPubMedPubMedCentralGoogle Scholar
  16. 16.
    Pal S, Juyal D, Adekhandi S, Sharma M, Prakash R, Sharma N, Rana A, Parihar A (2015) Mobile phones: reservoirs for the transmission of nosocomial pathogens. Adv Biomed Res 4:144.  https://doi.org/10.4103/2277-9175.161553 CrossRefPubMedPubMedCentralGoogle Scholar
  17. 17.
    Ruediger HW (2009) Genotoxic effects of radiofrequency electromagnetic filds. Pathophysiology 16:89–102CrossRefPubMedGoogle Scholar
  18. 18.
    Shahin-Jafari A, Bayat M, Shahhosseiny MH, Tajik P, Roudbar-Mohammadi S (2016) Effect of long-term exposure to mobile phone radiation on alpha-Int1 gene sequence of Candida albicans. Saudi J Biol Sci 23:426–433.  https://doi.org/10.1016/j.sjbs.2015.05.001 CrossRefPubMedGoogle Scholar
  19. 19.
    Soghomonyan D, Trchounian K, Trchounian A (2016) Millimeter waves or extremely high frequency electromagnetic fields in the environment: what are their effects on bacteria? Appl Microbiol Biotechnol 100:4761–4771.  https://doi.org/10.1007/s00253-016-7538-0 CrossRefPubMedGoogle Scholar
  20. 20.
    Taheri M, Darabyan M, Izadbakhsh E, Nouri F, Haghani M, Mortazavi SAR, Mortazavi G, Mortazavi SMJ, Moradi M (2017) Exposure to visible light emitted from smartphones and tablets increases the proliferation of Staphylococcus aureus: can this be linked to acne? J Biomed Phys Eng 7:163–168PubMedPubMedCentralGoogle Scholar
  21. 21.
    Torgomyan H, Trchounian A (2013) Bactericidal effects of low-intensity extremely high frequency electromagnetic field: an overview with phenomenon, mechanisms, targets and consequences. Crit Rev Microbiol 39:102–111CrossRefPubMedGoogle Scholar
  22. 22.
    Tubby S, Wilson M, Wright JA, Zhang P, Nair SP (2013) Staphylococcus aureus small colony variants are susceptible to light activated antimicrobial agents. BMC Microbiol 13:201.  https://doi.org/10.1186/1471-2180-13-201 CrossRefPubMedPubMedCentralGoogle Scholar
  23. 23.
    Ulger F, Esen S, Dilek A, Yanik K, Gunaydin M, Leblebicioglu H (2009) Are we aware how contaminated our mobile phones with nosocomial pathogens? Ann Clin Microbiol Antimicrob 8:7.  https://doi.org/10.1186/1476-0711-8-7 CrossRefPubMedPubMedCentralGoogle Scholar
  24. 24.
    Walia SS, Manchanda A, Narang RS, N A, Singh B, Kahlon SS (2014) Cellular telephone as reservoir of bacterial contamination: myth or fact. J Clin Diagn Res 8:50–53.  https://doi.org/10.7860/JCDR/2014/6398.3948 PubMedPubMedCentralGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2017

Authors and Affiliations

  1. 1.Department of Pharmacy“G. d’Annunzio” University, Chieti-PescaraChieti ScaloItaly

Personalised recommendations