Demographic data
After removing the invalid data, we finally obtained 47 valid questionnaires. The participants included 27 males (57.4%) and 20 females (42.6%). The mean age of all the patients was 53.09 ± 15.72 years. Thirty-four infected patients (72.3%) lived together with 2–3 family members, while 11 (23.4%) infected patients lived together with 4–6 family members. Only 2 (4.3%) infected patients lived together with more than 6 family members. The data showed that retirees were more likely to be infected with COVID-19, accounting for 34.4% (16/47) of all the patients. Nearly all of the patients (97.87%, 46/47) had confidence that they would recover from this infection.
Ocular symptoms
The ocular symptoms included blurred vision, conjunctival congestion, eye pain, photophobia, tearing, secretion, foreign body sensation, and inability to open the eyelid freely because of secretion or sticky feelings. The most common ocular symptom was secretion, which was present in 25 (53.19%) patients. Other symptoms that were also very common in the COVID-19-infected patients included foreign body sensation (21 patients, 44.68%), tearing (21 patients, 44.68%), conjunctival congestion or reddish eye (19 patients, 40.43%) and mild eye pain (19 patients, 40.43%). Fewer individuals presented with blurred vision (17 patients, 30.17%) and photophobia (13 patients, 27.66%). Additionally, 11 patients (23.4%) could not open their eyelid freely because of secretion or sticky feelings. We listed all the detailed data in Table 1.
As each of the self-reported symptoms or signs was given a weighted score of 1, 12 patients (25.5%) received a score of 0, which means they did not have any ocular symptoms. Conversely, 3 patients (6.4%) had scores of 8, which means that the individual had all the ocular symptoms listed above. Detailed information on the weighted scores is presented in Fig. 1.
These ocular symptoms can occur at any stage of the disease course, varying from 5 days before to 20 days after obtaining a confirmed diagnosis of COVID-19 infection by PCR. However, most of the patients presented with ocular symptoms in the early stage of infection, with a median of 1.35 (lower quartiles 0.25, upper quartiles 2.25) days after identification of the infection. However, this question was only answered by 30 patients.
Nasal symptoms and hand-to-eye/nose contact behaviour
Twenty-nine (61.7%) patients had nasal obstruction and running. Nineteen (40.4%) patients blew their nose more frequently than usual because of nasal symptoms. Direct hand-to-eye contact behaviour was evaluated by the number of times the eye was rubbed in one day. Most infected patients (63.8%, n = 30) rubbed their eyes 1–5 times with their hands in one day. In addition, 10.64% (5 patients) rubbed their eyes 6–10 times a day. A total of 2.13% of patients rubbed their eyes more than 10 times a day. Only 23.4% (11) of individuals denied hand-to-eye contact behaviour.
Additionally, we found that most patients did not wash their hands and face immediately after returning home in the week before diagnosis. Only 44.68% (21 patients) washed their hands immediately upon returning home more than 6 days per week. A total of 40.43% (19 patients) achieved this process 1–3 days per week. A total of 12.77% (6 patients) washed their hands immediately 4–5 days per week. One patient (2.13%) never washed his hands after returning home in the week before infection confirmation.
Compared to hands, much fewer people paid attention to washing their face immediately after returning home. Only 25.53% (12 patients) washed their faces immediately after returning home more than 6 days per week. Most infected individuals (23 patients, 48.94%) washed their face after returning home 1–3 days a week. Additionally, 21.28% (10 patients) of patients never washed their faces when they returned home. When they washed their faces, 38.3% (18 patients) also washed or cleaned their nasal cavity. Among these 18 patients, 11 (61.11%) preferred to clean their nasal cavity before washing the ocular portion of their face. When washing faces, 10.64% (5 patients) of patients shared towels with other family members. In addition, 48.94% (23 patients) used a basin to wash their face. Among them, 78.26% (18/23) shared the basin with others.
Correlation between ocular symptom grades and hand-to-eye/nose contact behaviour
Fisher’s exact test for cross table showed that only the increased frequency of blowing noses (p = 0.032, two sided), the frequency of washing hands (p = 0.025, two sided), and the frequency of rubbing eyes (p = 0.005, two sided) affected the ocular symptom grades. Other factors, including the frequency of washing faces, the way faces were washed, the use of a basin/towel or not, and the presence or absence of nasal obstruction/running, had no correlation with ocular symptom grades(Table 2).