A Metagenomic Deep Sequence Analysis of Infectious Conjunctivitis Etiology in Burkina Faso,
Africa and Berkeley, California
Gerami D. Seitzman1,2, Mamadou Bountogo3, Boubacar Coulibaly3, Ali Sie3, Kuniyoshi Kanai4, Meredith Whitesite4, Kevin Ruder,1,2, Cindi Chen1,2, Elodie Lebas1, Emily Colby1, Michael Deiner2, Thomas M. Lietman1,2, and Thuy Doan1,2 on behalf of the SCORPIO (Seasonal Conjunctivitis Outbreak Reporting for Prevention and Improved Outcomes) Study Group
1Francis. I Proctor Foundation, University of California, San Francisco, California USA; 2Department of Ophthalmology, University of California, San Francisco, California USA; 3Nouna Health Research Center (CRSN), Nouna, Burkina Faso, Africa;
4School of Optometry, University of California, Berkeley, California USA
Purpose: SCORPIO is an NEI-funded project to evaluate the causes of epidemic conjunctivitis around the world using metagenomic deep sequencing (MDS).
Background: Most cases of infectious conjunctivitis are not investigated microbiologically and presumed viral. Burkina Faso is a landlocked low-resource country in Western Africa, where seasonal epidemics of acute conjunctivitis occur in massive numbers. Over 780,000 cases have been reported in a four-year span. In contrast Berkeley, California has only isolated cases of infectious conjunctivitis.
Methods: Conjunctival swabs were obtained from patients with acute conjunctivitis symptoms for <14 days. Swabs were placed in DNA/RNA-Shield (Zymo Research) and transferred to a -20oC freezer for storage. Samples were shipped to the Proctor Foundation/UCSF on dry ice and stored at -80oC until tested. Details of sequencing, library preparation, and bioinformatics analyses have been previously described.
Results: In Burkina Faso, MDS identified a virus as the causative pathogen in 50% of the cases (10/19). Adenovirus was identified as the pathogen in 11% (2/19). Bacterial pathogens were identified in 26% (5/19) samples. No definitive pathogen was identified in 26% (6/19) samples. In Berkeley, MDS identified a virus as the pathogen in 29% (2/7) of call cases, one of which was adenovirus. Bacterial pathogens were identified in (3/7) and no identifiable pathogens in 29% (2/7). In both locations, unsuspected pathogens were identified where systemic treatment would be favored over observation.
Conclusions: In small samples of predominantly young patients in Burkina Faso, Africa and Berkeley, California, the causative pathogens of patients presenting with acute, mostly purulent, clinically presumed infectious conjunctivitis are surprising. Human adenoviruses were isolated in a minority of cases. In many countries, seasonal outbreaks of contagious conjunctivitis remain public health issues with school outbreaks and economic considerations with work absences. Effective surveillance and therapeutic strategies for conjunctivitis requires accurate identification of etiology.
Disclosure: S: R01EY032041;
C: Seitzman, work unrelated