Quantitative investigation of viral load in acute to subacute human adenovirus type 54 conjunctivitis

Evaluation of anti-adenoviral effects of the polyvinyl alcohol iodine ophthalmic solution

PURPOSE

To investigate the virucidal effects of a polyvinyl alcohol iodine, Saniode, against 16 types of human mastadenovirus (HAdV) causing ophthalmic, respiratory, gastrointestinal, urinary, and systemic infections.

STUDY DESIGN

Laboratory investigation METHODS: Fifty microliters of Saniode were exposed to 10 μL each containing HAdV virus stock solution of 1 × 106 copies/μL of HAdV-1, -2, -3, -4, 5, -6, -7, -8, -11, -37, -53, -54, -56, -64, -81, and -85 for 10 s, 30 s, 1 min, and 3 min. After neutralization with 0.5% sodium thiosulfate, the mixture was diluted by ten-fold serial dilution and inoculated into 24 wells containing confluent A549 cell monolayers. Virucidal effects were calculated relative to the positive control on days 7-10 and observed until 30 days post-infection.

RESULTS

Saniode satisfied the EN-14476 criterion for virucidal effects (>99.99%) for all HAdV types at all exposure times, including at 10 s on days 7 to 10 post-infection. All types of HAdVs that reacted for > 1 min achieved 99.99% reduction, including after 30 days.

CONCLUSION

Saniode displayed virucidal effects against all tested HAdV types. Currently, with no specific medication available for HAdVs in ocular infection, this could be an option to prevent the spread of keratoconjunctivitis.

Correlation of Adenoviral Titers with Severity of Adenoviral Conjunctivitis and Time to Viral Clearance for 21 Days

SIGNIFICANCE

This investigation reports the correlation of conjunctival viral titers in adenoviral conjunctivitis with patient-reported symptoms and clinician-graded signs for 21 days of follow-up.

PURPOSE

Adenoviral conjunctivitis is a highly contagious viral eye infection with significant morbidity and economic impact. This study investigates whether severity of signs and symptoms and time to viral clearance are correlated with conjunctival viral titers at baseline and during 21 days of follow-up.

METHODS

The Reducing Adenoviral Patient Infected Days study was a pilot study of the efficacy of a single in-office administration of ophthalmic 5% povidone-iodine. This article outlines longitudinal analyses after the primary outcome report. Of 212 participants screened, 28 participants with quantitative polymerase chain reaction-confirmed adenoviral conjunctivitis were randomized and had follow-up visits on days 1, 2, 4, 7, 14, and 21. At each visit, clinician-graded signs, participant-reported symptoms, and a conjunctival swab for quantitative polymerase chain reaction analysis were obtained. The correlation of viral titers with symptoms and signs was calculated: (1) cross-sectionally at each visit and (2) longitudinally for 21 days using a repeated-measures mixed-effects model.

RESULTS

Twenty-five of 28 participants had sufficient data for this report. Higher viral titers for 21 days were correlated with greater severity of symptoms (tearing, matting, and redness, r ≥ 0.70; P < .02) and greater severity of clinical signs (bulbar redness and serous discharge, r ≥ 0.60; P < .01). Eyes with highest baseline viral titers required longer time to viral clearance ( r = 0.59, P = .008). Signs and symptoms persisted in approximately half of the eyes even after viral clearance.

CONCLUSIONS

Higher conjunctival viral titers across 21 days were strongly correlated with more severe signs and symptoms and longer time to viral clearance. Our results also indicate that symptoms and signs can persist after viral clearance.

The relationship between clinical findings and viral load in Adenoviral Keratoconjunctivitis

The study aimed to evaluate the relationship between clinical findings and viral load in adenoviral keratoconjunctivitis (Ad-Kc). In this cross-sectional study, 30 eyes of 30 patients with Ad-Kc were enrolled. The real-time polymerase chain reaction was performed to detect and quantify adenovirus in all samples. The patient groups were divided into three subgroups according to baseline viral loads (<10⁷, 10⁷-10⁸, >10⁸ HAdV copies/ml). The follow-up duration, HAdV DNA copy number, treatment regimen, and detailed clinical findings including uncorrected visual acuity, eyelid edema, conjunctival hyperemia, chemosis, follicular reaction, corneal involvement, conjunctival pseudomembrane, and subepithelial infiltrates (SEIs) were recorded. The study showed that a high initial viral load was associated with the development of SEIs and pseudomembrane formation (p<0.05). Clinical findings and ocular complications of Ad-Kc were found similar in treatment groups at the final visit (p>0.05). Our results showed that a high initial viral load in Ad-Kc may be predictive of inflammatory sequelae. Determination of the initial viral load in Ad-Kc may be helpful to better understand the clinical course of the disease and prevent complications.