Do various personal hygiene habits protect us against influenza-like illness?

A cross-sectional study was undertaken in Riyadh city, the capital of Saudi Arabia.

Three thousand male and female youths and young adults aged from 16 to 45 years were selected. The authors were able to acquire their contact information through the official government Saudi Telecom database, which was clearly explained to them that the communication with them was purely for scientific purposes, and all data of their identities will remain confidential. A systematic random sampling of those randomly selected participant from different parts in Riyadh was applied using a computer generating system to make sure it is representative to the whole city.

The researcher first started by calling each participant. A full explanation was given to each participant in details (from the purpose of the research, consent to answer the questionnaire, to the explanation of the outcome definition). Each point of the questionnaire was explained to them to make sure they had excellent comprehension, and therefore, respond accurately. Survey Monkey program was used as it had easier presentation of the questions to the participant [18]. Next, the participants were asked to answer the questionnaire, which was designed to explore the participant’s personal hygiene habits, gender, age, social status, and level of education. The study questionnaire contained 20 questions regarding habits of personal hygiene and related information and four demographic questions. The participants were asked questions that were considered the study variables, which were as follows: hand hygiene habits, use of other personal items, the action is done when sneezing, influenza vaccination and the number of times they had influenza-like illness, in which all of these were asked to be answered from the participant’s past 4 weeks to minimize possible recall bias. The questionnaire was subjected to a pilot study by 36 youth and young adult volunteers. Further improvement and rephrasing were carried out accordingly. The influenza vaccination was considered a secondary investigation of the current research.

Different questions were asked. For example, in the past 4 weeks, do you wash your hands before eating? Always, sometimes, rarely, never. On your ordinary day, approximately how much time do you spend washing your hands? Less than 5 s, 5–10 s, 10–20 s, 20–30 s, More than 30 s. Do you wash your hands after handshaking? Always, sometimes, rarely, never. Do you wash your hands before handshaking? Do you wash your hands after getting back home? Do you wash your hands after getting out of the washroom (W.C)?

Do you use other people’s personal items? I use other people’s towels always, sometimes, rarely, never. I use other people’s used spoon. I share smoking shisha (habli babli) with others. I share the drinking straw with others. I share the same used drinking glass with others. I used to touch my eyes and nose? How many times do you get influenza-like illness in 1 year? 1–3 times/ year, 4–6 times / year, 7–10 times / year, more than 10 times / year. What do you do when you are about to sneeze? I sneeze on my hands; I sneeze on my clothes, I sneeze using napkins, I sneeze on my forearm, I sneeze on the air (empty space). Did you take the Influenza vaccine this year? Yes, no. If the answer yes in the previous question, do you take the Influenza vaccine every year? Yes, no.

The term influenza-like illness was defined based on the case definition of the World Health Organization, which is an acute respiratory infection with a measured fever of ≥38 C° and cough; with onset within the last 10 days [19].

The statistical package for social science version 17.0 (SPSS Inc. Chicago, IL) was used to analyze the collected data. Descriptive statistics and Odds Ratio and its 95% confidence intervals were used to determine the association between the frequency of influenza-like illness and the studied variables. Significant associations in the crude analysis were submitted into the multivariate logistic regression model, and the Odds Ratio was reported.

The authors had to make the age group from 16 to 45 years, as in Saudi Arabia, the middle age group of 16–64 makes up the greatest share of the total population (64.8%). There was a chance of recall bias among the participants. However, the participants were asked to answer the questions based on their behavior in the last 4 weeks, which minimized the recall bias. The duration of hand-washing reported by participants might not have been accurate 100%. However, they were asked to have an approximate estimation, as it is difficult to bring all participants in one place, and observe the time they spend washing their hands. Finally, there might have been some participants who did not answer the questionnaire as they should due to un-clear comprehension of the questions. However, this matter has been addressed since the beginning, as each participant was approached individually, and was given a full explanation of each part of the questionnaire.