Hand-to-face contact behaviors during indoor activities in daily life among Korean adults: an observational pilot study using videotaping

OBJECTIVES: Hand-to-face contact (HFC) is the major route for the self-inoculation of pathogens. This study aimed to describe the characteristics of HFC behaviors among Korean adults during indoor activities. METHODS: Thirty participants were enrolled in the study, and 2 hours of videotaped data were collected from each participant. Contact data were recorded by examining the frequency and duration of HFC on the videos. Three training sessions were conducted for 2 readers to ensure the accuracy and reliability of videotape reading. Re-reading and verification of selected video data were performed to confirm intrapersonal and interpersonal validity. Contact exposure (CE) was determined by multiplying the contact frequency (CF) by the contact duration (CD) to quantify the intensity of contact during the observation time (2 hours). RESULTS: A total of 3,007 HFCs (1,305 mucous membrane contacts and 1,702 non-mucous membrane contacts) were observed for 60 person-hours. The median CF (person/2 hr) of the mucous membranes (eye; 4.0, nose; 15.5, mouth; 16.5) was 39.5/person and the median total CD was 177.0 sec/person. The median CE (frequency-duration/sec/person) was 5,795.0 (mouth: 1,356.0, nose: 600.0, eye: 57.5). CONCLUSIONS: This study showed that the mouth and nose were the most frequent exposure sites for HFC. Avoiding habitual HFC, awareness of self-inoculation by HFC, and vigorous hand hygiene should be strengthened to prevent the spread of infections.