Investigation of SARS-CoV-2 in tear and conjunctival secretions of hospitalized patients with clinically-confirmed COVID-19 pneumonia

Abstract

Background The aim of this study was to demonstrate the presence of the virus in tear and conjunctival secretions of clinically-confirmed COVID-19 pneumonia patients. Methods This prospective study was conducted at Bakirkoy Dr. Sadi Konuk Training and Research Hospital (2020/190). Nasopharyngeal and ocular samples were obtained by swab technique and investigated by RT-PCR. Results A total of 83 patients were included. The mean age was 61.88 ± 16.04 years. 28.92% of the patients had mild, 65.06% moderate and 6.02% severe pneumonia radiologically. RT-PCR was positive in 31 (37.35%) patients in the first nasopharyngeal swabs and in 19 (22.89%) in the second swabs. 17 of 19 patients had positive both first and second nasopharyngeal swabs; only the second swabs of two patients were positive. The first conjunctival swabs RT-PCR were positive in 5 out of 83 clinically-confirmed patients or 33 laboratory-confirmed patients (rates: 6.02% and 15.15%). There were no positives detected in the second conjunctival swabs. Conclusions SARS-CoV-2 can be detected in the conjunctival swabs of patients with COVID-19 pneumonia.

Detection of coronavirus in tear samples of hospitalized patients with COVID-19

“…Only a few studies in the literature comparing CT values in ocular and nasopharyngeal samples have been published. Ares et al, Karabela et al, and Gijs et al reported results similar to ours [ 18 , 26 , 27 ].…”

Incidence and clinical characteristic of ocular surface manifestation: an evaluation of conjunctival swab results in Corona Virus 2019 (COVID-19) patients in Jakarta, Indonesia

“…The second probable reason was a fast clearance rate of the virus from the ocular surface due to drainage via the nasolacrimal pathway, evaporation, and its low volume [ 7 , 25 ]. The third reason was the fact that ocular secretions were known to have a strong local immune system (lactoferrin and immunoglobulins) against coronavirus[ 7 , 24 , 25 ]. Lastly, the low number of ACE-2 receptors to have been shown in conjunctival tissue (< 50% lower than other tissues), thus their ability to bind to the virus is very poor [ 25 , 26 ].…”

“…The third reason was the fact that ocular secretions were known to have a strong local immune system (lactoferrin and immunoglobulins) against coronavirus[ 7 , 24 , 25 ]. Lastly, the low number of ACE-2 receptors to have been shown in conjunctival tissue (< 50% lower than other tissues), thus their ability to bind to the virus is very poor [ 25 , 26 ]. It is also possible that the viruses appear at specific period of time in the ocular surface, thus requiring price collection time in order to gain positive results [ 10 , 27 ].…”

Covid-19 and its relation to the human eye: transmission, infection, and ocular manifestations

“…The first conjunctival swabs were positive in 5 out of 83 clinically confirmed patients or 33 laboratory-confirmed patients expressed as 6.02% and 15.15%, respectively. However, there were no positives detected in the second conjunctival swabs [ 37 ]. On the other hand, the nasopharyngeal swabs tested positive in 31 (37.35%) patients in the first nasopharyngeal swabs and 19 (22.89%) in the second swabs.…”

“…On the other hand, the nasopharyngeal swabs tested positive in 31 (37.35%) patients in the first nasopharyngeal swabs and 19 (22.89%) in the second swabs. Karabela et al mentioned that coronavirus can be detected in the conjunctival swabs of patients with Covid-19 pneumonia [ 37 ].…”