The overall knowledge of hand hygiene was high which was a positive finding. Table 2 shows that respondents have good knowledge on basic hand hygiene where about 70.0% answered 5.5 out of 8 questions correctly. This was perhaps due to their usual understanding on personal and hand hygiene, obtained from formal and informal training processes. Figure 3 revealed that that only 0.7% of participants (3 out of 434) had low knowledge level regarding hand hygiene and 99.31% of participants had good levels of knowledge of hand hygiene. The proportions of knowledge level in our study is higher compared to similar study for hand hygiene knowledge among healthcare workers 14 and similar survives for residents, nurses and students where the knowledge levels were found to be moderate 151617. Despite the lack of hand hygiene resources in Sudan hospitals, this finding is higher than that reported in other studies this is maybe due to that the knowledge guidelines are simple to learn, but translating them into skill in practice environment is a challenge. A more detailed view of knowledge scores in table 3, (70.7%) respondents answered correctly when asked about the main route of transmission of potentially harmful germs. Our results are comparable with other studies 18 which reported 72% of participants knew that the unhygienic hands of health care workers were the main route of transmission. Although participants in this current study had high knowledge of hand hygiene and achieved a satisfactory score on the knowledge questionnaire, the results showed deficits in their knowledge, most notably in the area of when to perform alcohol hand rub or handwashing, and time length to perform both hand wash and hand rub. Our findings were similar to a study carried out by Khaled M. Abdelaziz 23 at Ain Shams University, Cairo, where in 23.2% of observed candidates showed inappropriate hand washing time length (less than 30 seconds). Also this finding in line with the study done by Maheshwari et al, 15 where participants had answered below satisfaction level regarding the type of hand hygiene method required for decontaminant hands in the different clinical situations. Also, an important observation in this study (43%) of the participants answer that they can wear gloves as a substitute for hand hygiene and that was similar to study done by Wilcox et al, 24 for nurses showed that many nurses prefer to wear gloves instead of washing hands and to dispose it after using glove without washing hands and/or they use the same glove for different patients. This was in line with other studies describe that gloves may mistakenly be taken as a substitute for hand hygiene or as protection of the professional only 25. Also a previous study by Jang et al, 26 indicated that various health professionals have admitted to using the same pair of gloves, for long periods and in various activities, because they felt to be protected. Non removal of gloves between patients contributes to the transmission of pathogens and cross-infection 27. However, in our study the knowledge about 5 moments of hand hygiene by WHO, and handwashing right steps were good. But the poor knowledge about the time length for hand hygiene affects the quality of hand hygiene practices.

The  results of the current study showed a negative significant association between the knowledge about the hand hygiene of respondents and gender (P = 0.187), similar to other studies 2829 found that no significant difference between male and female health-care workers in terms of their knowledge about hand hygiene. The result of this study showed there is no significant difference in knowledge levels between the healthcare workers who had formal training of hand hygiene and who had not (P = 0.575). Also this consistent with a study in South Sudan 30 refute the association between and hygiene training and knowledge levels.

Our results showed that the perception finding was 197 of 437 participants (45.2%) had a good awareness of the importance of hand hygiene (positive perception), and 239 of participants (54.8%) had fair awareness of hand hygiene importance (negative perception).This  supports other studies in the extanal literature, such as the investigation in Korea by Kim et al.,31 which found that the perception toward hand hygiene among health-care workers is poor. In contrast, in a study among health-care workers in Switzerland, Pessoa-Silva et al. 3233 reported that 64% of the respondents have a positive perception of hand hygiene.

The age, the type and nature of the hospital, and the formal training courses was significantly affecting the perception of hand hygiene. Higher perception was found in participants who are working in private hospitals and specialized hospitals. The HCWs who get formal training courses of hand hygiene were found to have better perception than those who didn t. The training courses of hand hygiene were significant factor affect the perception of hand hygiene importance among HCWs. The higher perception of HCWs upon hand hygiene importance that assessed in the private and specialized hospitals may be due to better resource availability than public, general, and teaching hospitals. We suggest to encourage the positive hand hygiene environment, that can be led by management to guarantee continues presentation of role model and the feedback response to support the good practice of hand hygiene. Also the instructional papers of hand washing, hand disinfecting and training courses may be useful in reminding staff with the need to perform hand hygiene and that is similar to suggestions by Birks et al.34. These findings are supported by the findings of some studies, 3132333435 and conflicting with other. 36.

Generally; the results obtained from this study confirmed that there is an improvement in Sudanese HCWs awareness compared to a previous study done in 2009 assess the awareness to use alcoholic formulations among ICU workers in 3 Sudanese tertiary hospitals which show that it was very low (2.8%). 19 Also compared to another study there was improvement regarding the time to perform hand disinfection in this study with a similar study done in specialized Sudanese hospital in 2010; wherein this study the perception in performing hand disinfection before and after touching the patient was high (96.6%), while in 2010 study hand disinfection was more after (68.1%) than before (39.1%) touching the patient and thus aware to protect themselves rather than to protect patients at that time 20. This may indicate that good effort in educating and training HCWs was done since 7-8 years ago. So our findings implied that full compliance with hand hygiene guidelines may be unrealistic and difficult, but continuous interventions in educating and training HCWs that aimed at improving hand hygiene attitudes and habits may be effective in increasing knowledge and perception which accordingly would lead to better compliance and adherence to hand hygiene practice.  

The  major limitations of this study that the data about hand hygiene evaluated based on information provided by health care workers through self-administered questionnaires instead of observing hand hygiene practices as well as individual opportunities and observations. Usually; data regarding personal practices and behaviors are subjected to informant bias. In addition, the data presented in this study are self-reported and partly dependent on the participants' honesty and recall ability; thus, they may be subject to recall bias. The other limitation is that data collection was done as online survey through social media rather than personal interviews or focus groups. In-person interviews allow you to not only ask the network planned questions but to probe more deeply into an individual s response. Focus group; which are essentially guided conservation, can help in eliciting information underlying complex behavior and motivation.