NEHA October 2023 Journal of Environmental Health

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high (10 7 PFU/cm 2 ) and low (10 3 PFU/cm 2 ) concentrations are shown in Table 3. The transfer rates from surfaces to hands were found to be higher when compared with hands to surface. The only exceptions to this finding were at the low concentration, where hands to desk (37% versus 38%), door han- dle (28% versus 29%), and faucet (both 29%) were slightly higher or equal. At the high concentration, all surfaces were found to have transfer rates above 50% and above the detection limit of 0.9 log PFU/cm 2 . Bathroom faucets had the highest transfer rate at 74%. At the low concentra- tion, light switches had the highest transfer rate at 45% and were the only surface above the detection limit. Curtains had the lowest transfer rate at 20%. Previous research has indicated that clean- ing is an important factor for hotel selection by consumers and that specific customer seg- ments are willing to pay more for enhanced cleaning methods (Zemke et al., 2015). Thus, increased vigilance in cleaning procedures would be beneficial for public health as well as for hotel business. Conclusion According to our study results, phi 6 bacte- riophages—a surrogate of the SARS-CoV-2 virus—can survive for up to 4 days on light switches, remote controls, and bathroom faucets; up to 3 days on hotel room beds, wooden desks, door handles, and hotel ame- nities; and up to 2 days on the carpet, hotel room curtains, and leather coupon samples. Our findings suggest that high-touch areas in hotel guest rooms could be a potential source of virus transmission, and cross-contamina- tion from these surfaces to hands and vice versa is possible and perhaps even likely. Therefore, based on our data, it is recom- mended that hotel businesses establish stan- dard operating procedures (SOPs) to ensure that these potential hot spots are eectively

TABLE 3

Transfer Rate of Phi 6 From Hotel Guest Room Surfaces to Hands

Log and Transfer Rate With Low Level Inoculation (10 3 PFU/cm 2 )

Surface

Log and Transfer Rate With High Level Inoculation (10 7 PFU/cm 2 )

Log PFU/cm 2

Transfer Rate b (%)

Transfer Rate (%)

Log PFU/cm 2 a

Bed to hands Desk to hands Light switch to hands Door handle to hands Remote control to hands Room curtain to hands Hotel amenities to hands Leather to hands Bathroom faucet to hands

2.0 ± 0.2 1.6 ± 0.1 2.1 ± 0.2

50 63 57

0.4 ± 0.3 0.7 ± 0.2 0.9 ± 0.2

25 37 45

1.9 ± 0.3

0.5 ± 0.3

1.6 ± 0.4

0.6 ± 0.2

1.5 ± 0.3

0.3 ± 0

1.7 ± 0.1

0.4 ± 0.1

1.4 ± 0.1 2.3 ± 0.2

50 74

0.3 ± 0.1 0.6 ± 0.3

20 29

a Mean and standard deviation of phi 6 from each inoculated hotel guest room surface (10 7 or 10 3 PFU/cm 2 ) to hands after touching each inoculated surface for 20 s ( N = 6). b The transfer rate of mean and standard deviation of phi 6 from each inoculated hotel guest room surface (10 7 or 10 3 PFU/cm 2 ) to hands after touching each inoculated surface for 20 s ( N = 6).

cleaned to minimize the risk of potential virus transmission. Although CDC (2021) and AHLA (2020b) have provided enhanced cleaning and disinfecting guidelines to aid the hotel industry in specific protocols for minimizing risk, SOPs are still needed. The results from our study might not rep- resent a real-world hotel room environment, as our experiments were conducted under laboratory conditions and the surfaces were inoculated with a high concentration of phi 6 to simulate a worst-case scenario. Thus, more research is needed to investigate potential viral transmission via hotel room surfaces to confirm our findings.

Acknowledgement: The authors acknowledge the Food Safety Research Funds at the Con- rad N. Hilton College of Global Hospitality Leadership. Furthermore, the authors declare no conflict of interest in the publication of this article. Corresponding Author: Sujata A. Sirsat, Asso- ciate Professor, Conrad N. Hilton College of Global Hospitality Leadership, University of Houston, 4450 University Drive, S230, Hous- ton, TX 77204-3028. Email: sasirsat@central.uh.edu.

References

Almanza, B.A., Kirsch, K., Kline, S.F., Sirsat, S., Stroia, O., Choi, J.K., & Neal, J. (2015a). How clean are hotel rooms? Part I: Visual observations vs. microbiological contamination. Journal of Envi- ronmental Health , 78 (1), 8–13.

Almanza, B.A., Kirsch, K., Kline, S.F., Sirsat, S., Stroia, O., Choi, J.K., & Neal, J. (2015b). How clean are hotel rooms? Part II: Examin- ing the concept of cleanliness standards. Journal of Environmental Health , 78 (1), 14–18.

Volume 86 • Number 3