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Introduction

This preprint is a timely and useful addition to the current conversations about hygiene habits after the pandemic. The study looks at how people in India, Pakistan, Saudi Arabia, and the United Arab Emirates (UAE) wash their hands and whether the cleaning chemicals they use still work even though they wash their hands less often. The authors use observational data from 901 individuals along with in vitro testing of the antimicrobial effectiveness of body washes, hand washes, and sanitizers that are already on the market. Their main argument is that well-formulated hygiene products can still achieve significant pathogen reduction within short contact times, even though global guidelines recommend longer handwashing durations.

The research brings up crucial issues concerning how hygiene products are made and how public health messages are sent, but there are some problems with the study's design, generalizability, and possible conflicts of interest that need to be looked at closely.

Strengths

The study underlines the gap between suggested and actual hand cleanliness behaviors, a critical issue in infection management. By using videography for behavioral observation, the study improves its validity by lowering reliance on self-reported data, which is susceptible to recall bias.

Furthermore, combining behavioral data with laboratory efficacy testing creates a useful framework for determining whether marketed hygiene products are suitable for real-world use. The use of standardized antimicrobial testing procedures, such as ASTM E2783-22 for bactericidal activity and ASTM E1052-20 for virucidal efficacy, adds credibility to the study's conclusions.

Concerns and Limitations

Despite its merits, the study raises concerns. The most crucial issue is the potential conflict of interest, as all authors are linked with Unilever, the business that manufactures the studied hygiene products. This raises issues about bias, especially since no independent laboratories evaluated the antimicrobial efficacy data and the study did not compare Unilever formulations to competing products. Because there is no benchmarking component, it is difficult to determine whether the claimed effectiveness is unique to these products or a characteristic of all well-formulated hygiene cleansers.

Furthermore, the study's observational data has significant limitations in terms of generalizability. The sample size of 901 participants, while instructive, is insufficient to draw broad conclusions about global hand hygiene behaviors. Furthermore, the study is limited to urban populations, leaving out rural groups where access to hygiene goods and adherence to hygiene practices may vary greatly. Furthermore, the study did not stratify findings by crucial demographic parameters such as age, gender, or socioeconomic status, resulting in a missed chance to learn how hygiene behaviors change among population groups.

Pathogen testing's scope is another constraint. The study compares bacterial efficacy against Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus to virucidal efficacy against Influenza A (H1N1) and Respiratory Syncytial Virus (RSV). However, it excludes non-enveloped viruses like norovirus, which are more resistant to surfactants and disinfectants.

Another issue is that the study focuses on product efficacy at short contact times, which may imply that shorter handwashing durations are equally protective. This violates public health guidelines, which emphasizes good technique, friction, and coverage above product formulation alone. Public health messaging should continue to prioritize behavioral adherence rather than relying exclusively on formulation improvement.

Areas for Improvement

Refinements may improve the study's credibility and impact. The methodology section might benefit from more clarity about inter-observer reliability in video analysis, as well as a more thorough discussion of ethical considerations in video data collecting, such as participant consent and data privacy. Furthermore, the statistical analysis of antimicrobial efficacy results should incorporate confidence intervals and significance testing to determine microbial decrease variability.

A comparison analysis of various hygiene brands could also be useful for the study. Researchers could better determine whether the stated efficacy is unique to Unilever formulas or constant across similar items if they evaluated many commercial products. Extending the study's scope to include non-enveloped viruses and potential AMR threats would provide a more complete picture of hygiene product performance.

Conclusion

This preprint gives useful information about post-pandemic hygiene practices and the antibacterial efficacy of marketed formulations. However, the study is restricted by its strong industrial association, low breadth of pathogen testing, and lack of independent confirmation. Future research should include third-party verification, increase the diversity of study participants, and compare tested goods to competitive formulations.

Competing interests

The authors declare that they have no competing interests.