Outpatient human coronavirus associated conjunctivitis in India

Abstract

Background: Viral conjunctivitis (pink eye) can be highly contagious and is of public health importance. There remains significant debate whether SARS-CoV-2 can present as a primary conjunctivitis. The aim of this study was to identify pathogens associated with outpatient infectious conjunctivitis during the COVID-19 Delta surge.

Methods: This prospective study was conducted in the spring and summer months of 2021. 106 patients with acute conjunctivitis who presented to the Aravind Eye Center in Madurai, India were included. One anterior nasal swab and one conjunctival swab of each eye were obtained for each enrolled patient. Samples were subsequently processed for unbiased metagenomic RNA deep sequencing (RNA-seq). Outcomes included clinical findings and codetection of other pathogens with SARS-CoV-2 in patients with conjunctivitis.

Results: Among the 13 patients identified with human coronavirus RNA fragments in their swabs, 6 patients had SARS-CoV-2 infection, 5 patients had coinfections of SARS-CoV-2 and human adenovirus (HAdV), 1 patient had a coinfection with human coronavirus OC43 and HAdV, and 1 patient had a coinfection of Vittaforma corneae and SARS-CoV-2. 30% had bilateral disease and symptoms on presentation. Petechial hemorrhage was noted in 33% of patients with SARS-CoV-2 infection. No patients with SARS-CoV-2 or SARS-CoV-2 and HAdV infections had subepithelial infiltrates on presentation. All patients denied systemic symptoms.

Conclusions: Among the patients presented with conjunctivitis associated with human coronavirus infection, over 50% of the patients had co-infections with other circulating pathogens, suggesting the public-health importance of broad pathogen testing and surveillance in the outpatient conjunctivitis population.

Keywords: Conjunctivitis; Coronavirus; Delta surge; India; SARS-CoV-2.

Fig. 1

Characteristics of metagenomic RNA deep sequencing. Number of sequencing read counts as a function of total, host, and non-host for 318 samples. Each dot represents a sample. Bars represent mean and standard deviation.

Fig. 2

Identification of human coronaviruses by metagenomic RNA deep sequencing. A. Alignment of detected SARS-CoV-2 sequencing reads to the SARS-CoV-2 genome (NCBI reference sequence NC_045512) for each positive sample. B. Alignment of detected human coronavirus OC43 reads in the nasal sample of patient #7 to the NCBI reference sequence NC_006213.1. Abbreviations: OD, right eye; OS, left eye; N, nasal.

Fig. 3

Cases of human coronavirus-associated conjunctivitis during the Delta coronavirus variant surge at the Aravind Eye Center in southern India. Stacked bar graph of conjunctivitis cases enrolled in the study. Solid gray bar represents the stoppage of clinical activities at the Aravind Eye Center. Dotted gray line represents the new confirmed SARS-CoV-2 cases in the population in the Tamil region of India.

Fig. 4

Representative external ocular photos of patients with human coronavirus infections. Each row of images represents the right and left eyes of a unique patient. Abbreviations: HAdV, human adenovirus; HCoV-OC43, human coronavirus OC43; SARS-CoV-2, severe acute respiratory syndrome coronavirus 2.