PURPOSE: Conjunctivitis epidemics and pandemics remain a global burden. This study aims to comprehensively identify pathogens associated with conjunctivitis in Vietnam.

METHODS: Patients with acute conjunctivitis presented to an outpatient clinic in Ho Chi Minh City, Vietnam, were enrolled from September 2022 to March 2023. Swabs were obtained from conjunctiva and anterior nares of all patients. Unbiased RNA deep sequencing (RNA-seq) was used to identify any replicating pathogens in the samples.

RESULTS: Samples from 35 patients were analyzed. A pathogen was identified in 80% of the patients. 72% (95% confidence interval: 54% to 85%) were infected with either HAdV-D or HAdV-B. RNA viruses detected were rhinoviruses and human coronavirus 229E. Bacteria etiologies included , , and One patient had co-infection of rhinovirus A and HAdV-B. , a fungus, was identified in one patient. Corneal sub-epithelial infiltrates, pseudomembranes, or pre-auricular lymphadenopathy were not reported in any patient.

CONCLUSIONS: Human adenoviruses are the common circulating pathogens associated with infectious conjunctivitis in Vietnam. HAdV species, however, appear to vary between geographic locations within Vietnam. Other under-recognized pathogens identified in this study, such as RNA viruses, suggest broader pathogen surveillance may be beneficial.