Survey of Viral Signatures (Virome) among Patients with Microbial Keratitis

Abstract

Purpose : To document the presence and diversity of viral signatures in contact lens case ecosystems associated with patients presenting with microbial keratitis.

Methods : We used whole genome sequencing to document the prevalence and diversity of viral signatures in 28 contact lens cases including Herpesviruses, Molluscum contagiosum, and members of the Giant viruses families and in 14 patients with culture positive and culture negative microbial keratitis.

Results : While diverse (n=590 species), relative abundance for viral signatures were low (<1%, 46,597 tags) compared to bacterial signatures (44,275,248 tags). One third of the identified viral signatures were associated with bacteriophages, which harbored virulence factors and antibiotic resistance genes to common ocular pathogens. These were documented in all cases from all patients. The highest relative abundance among the remaining 8459 signatures (18.1%) included Human endogenous retrovirus K (42.4%, n=3590, 11 samples, 6 patients), Pandoravirus salinus giant virus (27.4%, n=2320, 26 samples, 14 patients), Pandoravirus dulcis giant virus (13.9%, n=1179, 16 samples, 8 patients) and Hepatitis C virus (5%,n=487, 17 samples, 11 patients) . All four isolates were significantly more likely to be associated with culture and Acanthamoeba positive (P<0.0001) samples. Less than 1% (n=134) of the viral signatures were documented for members of the Herpesviruses family, Molluscusm contagiosum (n=74) and Human mastadenovirus C (SEROTYPE 2, EKC, n=2).

Conclusions : Both acanthamoeba associated and non-acanthamoeba associated contact lens ecosystems may serve as reservoirs and possible transmission vehicles for common and uncommon viruses. The role of giant viruses among this group is yet to be determined.

This is a 2020 ARVO Annual Meeting abstract.