Discussion

Hand hygiene is one of the most effective measures to reduce the spread of pathogens and prevent infections. ¹ The level of knowledge regarding the effectiveness of hand hygiene among our participants is high as almost all of them knew that hand hygiene can protect against the spread of infection from person to person by means of hands and surfaces. The study found that two-thirds of participants believed that hand hygiene with an alcohol-based hand rub is most appropriate for the community. This is probably because the alcohol-based hand rub is convenient and requires less time for application. ^{Reference Chan and Chan7} The study also found an association between this belief and health majors, which may be due to the common practices of hand hygiene with an alcohol-based hand rub among health professionals in their daily practice that have influenced health students. ^{Reference Chan and Chan7} Almost all students washed their hands before wearing (99.5%) and after removing (99.3%) a face mask. Once again, the study found a statistical association between health majors and hand hygiene with an alcohol-based hand rub when study participants washed their hands before wearing a face mask. Most (92.6%) students washed their hands when hands are both visibly dirty and not visibly dirty which is good, while the remaining (7.4%) students reported to wash hands only when hands are visibly dirty only.

In addition, although WHO recommends hand hygiene with water and soap when hands are visibly dirty, ^{Reference Chan and Chan7} 18% of our participants washed their hands with an alcohol-based hand rub in this situation and health majors were statistically associated with these practices. The findings of our study show that, although the proportion of hand hygiene compliance is high among study participants, health students tend to practice hand hygiene with alcohol-based handrub in all situations, including those that require hand hygiene with water and soap. This highlights an urgent need to improve community education to help reinforce correct hand hygiene.

WHO emphasizes an important role of community members in fighting COVID-19 by adopting frequent hand hygiene as part of their day-to-day practices. ^{Reference Chan and Chan7} WHO has also indicated 7 specific situations in which handwashing must be performed. ^{Reference Chan and Chan7} However, the proportions of those who washed their hands often in a normal day and after sneezing or coughing were suboptimal in our study. Although we did not examine reasons for not regularly performing hand hygiene, the availability of handwashing equipment would have an impact on hand hygiene practices. ^{Reference Jing, Pei Yi and Bose8}

There are five 7-level buildings with several lecture rooms on each level at Phenikaa University. Of these buildings, 2 toilets with 6 handwashing with soap and clean water stations in each toilet were available on each level. Two hand hygiene stations with an alcohol-based hand rub were provided in each lecture room. A special team was responsible for regularly checking these hand hygiene stations to make sure they were in working order and refilling soap and alcohol-based hand rub. However, hand dryers and disposable paper towels to dry hands were not available at all handwashing stations at the time the study was conducted. Given it is important to thoroughly dry hands after each wash, the unavailability of hand-drying equipment could be attributable to the suboptimal hand hygiene frequency in our study participants. In addition, hand hygiene with an alcohol-based hand rub can cause skin reactions with symptoms such as dryness, pruritus, and erythema. ^{Reference Jing, Pei Yi and Bose8} This may adversely affect the willingness to perform hand hygiene with an alcohol-based hand rub among our study participants.

A comparable study was conducted to examine the levels of hand hygiene practices in the Vietnamese community in the middle of 2020. ^{Reference Huong, Hoang and Tuyet-Hanh9} Although this study did not examine the hand hygiene frequency like ours, this study found that 39.4% of their respondents did not perform handwashing, when necessary, which is in line with our findings. ^{Reference Huong, Hoang and Tuyet-Hanh9} The COVID-19 outbreak was under good control in Vietnam at the time when that study and our study were conducted. Perhaps, this made our study participants feel reluctant to frequent wash their hands, which was originally not their habit. Given the ongoing COVID-19 pandemic, this emphasizes the importance of continuous community education regarding hand hygiene practices as a disease prevention and control measure. The role of coughs and sneezes in disseminating respiratory pathogens has been well documented. ^{Reference Dhand and Li10} The respiratory transmission of the SARS-CoV-2 virus that causes COVID-19 is mainly by respiratory droplets created by coughs and sneezes. ^{Reference Dhand and Li10} In light of this, it is important to educate the community that a simple, effective measure to minimize the spread of COVID-19 is to not only covering coughs and sneezes, but also performing correct hand hygiene right after this action.

This study has some limitations. Given it was a single-center study, the study population may not be representative of all Vietnamese university students. Nevertheless, 81% of all enrolled students of one of the largest multidisciplinary universities in Vietnam were participated in our study. Given COVID-19 is a novel disease, there was no internationally validated questionnaire developed to examine hand hygiene practices and other preventive measures in the community. The questionnaire used in this study was developed based on the recommendations of WHO and Vietnam Ministry of Health. ^1,2,6 To the best of our knowledge, most similar, published studies also used questionnaires that were developed by the same method as ours.