Adenovirus type 8 keratoconjunctivitis--an outbreak and its treatment with topical human fibroblast interferon

Natural history of adenoviral conjunctivitis in a US-based population: Viral load, signs, and symptoms

PURPOSE

To report the clinical signs, symptoms, and viral clearance in individuals in the United States with adenoviral conjunctivitis (Ad-Cs).

METHODS

Individuals ≥ 18 years presenting within 4 days of symptoms of Ad-Cs who met eligibility criteria and tested positive with both point-of-care immunoassay antigen and quantitative polymerase chain reaction (qPCR) testing were enrolled. Patient-reported symptoms, clinician-graded signs, and qPCR viral titers were collected at baseline, days 1-2, 4 (days 3-5), 7 (days 6-10), 14 (days 11-17) and 21 (days 18-21).

RESULTS

There was no detectable viral titers by the day 14 visit in 6/8 patients. By day 21, there was no detectable viral titers in the 7 participants who completed the visit; however, signs and symptoms persisted including: blurry vision (5/7), discomfort (2/7) or redness (1/7). Masked clinicians also noted conjunctival redness (4/7), follicular conjunctivitis (4/7) and bulbar edema (3/7).

CONCLUSION

Many patient-reported symptoms and clinical signs persist after viral titers are no longer detectable by qPCR. Using clinical signs and symptoms to determine quarantine duration may result in patients being furloughed longer than the time that the patient is infectious.

Topical pharmacologic interventions versus placebo for epidemic keratoconjunctivitis

BACKGROUND

Viruses cause about 80% of all cases of acute conjunctivitis. Human adenoviruses are believed to account for 65% to 90% of cases of viral conjunctivitis, or 20% to 75% of all causes of infectious keratoconjunctivitis worldwide. Epidemic keratoconjunctivitis (EKC) is a highly contagious subset of adenoviral conjunctivitis that has been associated with large outbreaks at military installations and at medical facilities. It is accompanied by severe conjunctival inflammation, watery discharge, and light sensitivity, and can lead to chronic complications such as corneal and conjunctival scarring with discomfort and poor quality of vision. Due to a lack of consensus on the efficacy of any pharmacotherapy to alter the clinical course of EKC, no standard of care exists, therefore many clinicians offer only supportive care.

OBJECTIVES

To assess the efficacy and safety of topical pharmacological therapies versus placebo, an active control, or no treatment for adults with EKC.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL, which contains the Cochrane Eyes and Vision Trials Register; 2021, Issue 4); Ovid MEDLINE; Ovid Embase; Latin American and Caribbean Health Sciences database (LILACS); ClinicalTrials.gov; and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP), with no restrictions on language or year of publication. The date of the last search was 27 April 2021.

SELECTION CRITERIA

We included randomized controlled trials in which antiseptic agents, virustatic agents, or topical immune-modulating therapy was compared with placebo, an active control, or no treatment.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methodology.

MAIN RESULTS

We identified 10 studies conducted in Asia, Europe, the Middle East, and North Africa with a total of 892 participants who were treated for 7 days to 6 months and followed for 7 days up to 1.5 years. Study characteristics and risk of bias In most studies participants were predominantly men (range: 44% to 90%), with an age range from 9 to 82 years. Three studies reported information on trial registration, but we found no published study protocol. The majority of trials had small sample sizes, ranging from 18 to 90 participants enrolled per study; the only exception was a trial that enrolled 350 participants. We judged most studies to be at high or unclear risk of bias across risk of bias domains. Findings We included 10 studies of 892 EKC participants and estimated combined intervention effects in analyses stratified by steroid-containing control treatment or artificial tears. Six trials contributed to the comparisons of topical interventions (povidone-iodine [PVP-I], trifluridine, ganciclovir, dexamethasone plus neomycin) with artificial tears (or saline). Very low certainty evidence from two trials comparing trifluridine or ganciclovir with artificial tears showed inconsistent effects on shortening the mean duration of cardinal symptoms or signs of EKC. Low certainty evidence based on two studies (409 participants) indicated that participants treated with PVP-I alone more often experienced resolution of symptoms (risk ratio (RR) 1.15, 95% confidence interval (CI) 1.07 to 1.24) and signs (RR 3.19, 95% CI 2.29 to 4.45) during the first week of treatment compared with those treated with artificial tears. Very low certainty evidence from two studies (77 participants) suggested that PVP-I or ganciclovir prevented the development of subepithelial infiltrates (SEI) when compared with artificial tears within 30 days of treatment (RR 0.24, 95% CI 0.10 to 0.56). Four studies compared topical interventions (tacrolimus, cyclosporin A [CsA], trifluridine, PVP-I + dexamethasone) with topical steroids, and one trial compared fluorometholone (FML) plus polyvinyl alcohol iodine (PVA-I) with FML plus levofloxacin. Evidence from one trial showed that more eyes receiving PVP-I 1.0% plus dexamethasone 0.1% had symptoms resolved by day seven compared with those receiving dexamethasone alone (RR 9.00, 95% CI 1.23 to 66.05; 52 eyes). In two trials, fewer eyes treated with PVP-I or PVA-I plus steroid developed SEI within 15 days of treatment compared with steroid alone or steroid plus levofloxacin (RR 0.08, 95% CI 0.01 to 0.55; 69 eyes). One study found that CsA was no more effective than steroid for resolving SEI within four weeks of treatment (RR 0.84, 95% CI 0.67 to 1.06; N = 88). The evidence from trials comparing topical interventions with steroids was overall of very low level certainty. Adverse effects Antiviral or antimicrobial agents plus steroid did not differ from artificial tears in terms of ocular discomfort upon instillation (RR 9.23, 95% CI 0.61 to 140.67; N = 19). CsA and tacrolimus eye drops were associated with more cases of severe ocular discomfort, and sometimes intolerance, when compared with steroids (RR 4.64, 95% CI 1.15 to 18.71; 2 studies; N = 141). Compared with steroids, tacrolimus did not increase the risk of elevated intraocular pressure (RR 0.07, 95% CI 0 to 1.13; 1 study; N = 80), while trifluridine conferred no additional risk compared to tear substitute (RR 5.50, 95% CI 0.31 to 96.49; 1 study; N = 97). Overall, bacterial superinfection was rare (one in 23 CsA users) and not associated with use of the intervention steroid (RR 3.63, 95% CI 0.15 to 84.98; N = 51). The evidence for all estimates was of low or very low certainty.

AUTHORS' CONCLUSIONS

The evidence for the seven specified outcomes was of low or very low certainty due to imprecision and high risk of bias. The evidence that antiviral agents shorten the duration of symptoms or signs when compared with artificial tears was inconclusive. Low certainty evidence suggests that PVP-I alone resolves signs and symptoms by seven days relative to artificial tears. PVP-I or PVA-I, alone or with steroid, is associated with lower risks of SEI development than artificial tears or steroid (very low certainty evidence). The currently available evidence is insufficient to determine whether any of the evaluated interventions confers an advantage over steroids or artificial tears with respect to virus eradication or its spread to initially uninvolved fellow eyes. Future updates of this review should provide evidence of high-level certainty from trials with larger sample sizes, enrollment of participants with similar durations of signs and symptoms, and validated methods to assess short- and long-term outcomes.

Efficacy of a Single Administration of 5% Povidone-Iodine in the Treatment of Adenoviral Conjunctivitis

PURPOSE

To evaluate the safety and efficacy of a single, in-office administration of 5% povidone-iodine (PVP-I) compared to artificial tears (AT) for adenoviral conjunctivitis (Ad-Cs).

DESIGN

Double-masked pilot randomized trial.

METHODS

Patients presenting with presumed adenoviral conjunctivitis were screened at 9 U.S. clinics.

INCLUSION CRITERIA

≥18 years of age, symptoms ≤4 days, and a positive AdenoPlus test.

EXCLUSION CRITERIA

thyroid disease, iodine allergy, recent ocular surgery, and ocular findings inconsistent with early-stage Ad-Cs. Randomization was to a single administration of 5% PVP-I or AT in 1 eye and examinations on days 1-2, 4, 7, 14, and 21 with conjunctival swabs taken at each visit for quantitative polymerase chain reaction. Primary outcome was percent reduction from peak viral load. Secondary outcomes were improvement in clinical signs and symptoms.

RESULTS

Of 56 patients randomized, 28 had detectable viral titers at baseline. Day 4 posttreatment, viral titers in the 5% PVP-I and AT groups were 2.5% ± 2.7% and 14.4% ± 10.5% of peak, respectively (P = .020). Severity of participant-reported tearing, lid swelling, and redness as well as clinician-graded mucoid discharge, bulbar redness, and bulbar edema were lower in the 5% PVP-I group than AT group on day 4 (P < .05). After day 4, viral titers and severity of signs and symptoms decreased markedly in both groups and no differences between groups were detected.

CONCLUSIONS

Pilot data suggest a single, in-office administration of 5% PVP-I could reduce viral load and hasten improvement of clinical signs and symptoms in patients with Ad-Cs.

An outbreak of epidemic keratoconjunctivitis caused by human adenovirus type 8 in primary school, southwest China

Background

Two outbreaks of epidemic keratoconjunctivitis (EKC) occurred successively with an interval of 5 days in two primary boarding schools in Weixi Lisu Autonomous County, Diqing, and Tibetan Autonomous Prefecture, Yunnan. The aims of this study were to determine the intensity and characteristics of the outbreaks, as well as the clinical manifestations in the patients, the risk factors for infection and the pathogen responsible for the two outbreaks.

Methods

An outbreak investigation was conducted in two primary schools, and a case-control study including patients from the Weixi County Ethnic Primary School was performed. Relevant specimens were collected according to the case definition, and next-generation sequencing was employed to identify the pathogen. An epidemiological investigation method was used to analyse the related epidemiological characteristics, such as risk factors. The phylogenetic tree was constructed by MEGA 7.0.

Results

A total of 331 acute conjunctivitis cases, including probable cases of EKC, were reported in the two schools, and the attack rates were 30.59% (171/559, 95%CI: 26.76–34.42) and 20.41% (160/784, 95%CI: 17.58–23.24), respectively. Cases occurred in all grades and classes in both schools, and only one staff member in each school presented illness. The epidemics lasted for 54 days and 45 days, respectively. The patients had typical manifestations of EKC, such as acute onset, follicular hyperplasia, pseudomembrane formation, preauricular lymphadenopathy, corneal involvement and blurred vision, and a relatively long disease course (average 9.40 days, longest 23 days and shortest 7 days). The risk factor for infection was close contact with a patient or personal items contaminated by a patient. The pathogen responsible for the outbreaks was HAdV-8. The virus was highly similar to the 2016 HAdV-8 strain from Tibet, China.

Conclusions

This study strongly suggests that HAdV-8 could lead to serious consequences. This is the second report of a HAdV-8-associated EKC outbreak in mainland China. Tibetan HAdV-8 might be circulating in southwest China; therefore, it is necessary to monitor the pathogens causing acute conjunctivitis in this area.

Oral steroid therapy as an adjuvant treatment for severe epidemic keratoconjunctivitis in patients younger than 3 years

PURPOSE

To evaluate the therapeutic effect of oral steroids given to patients younger than 3 years with epidemic keratoconjunctivitis (EKC) accompanied by severe eyelid edema and inflammatory ptosis, in whom eye drops were not feasible.

METHODS

This study included 9 patients treated for EKC in local clinics whose condition failed to improve due to severe eyelid swelling together with difficulties in application of eye drops and pseudomembrane removal. We analyzed the extent of eyelid swelling, corneal damage, follicles, chemosis, and pseudomembrane formation in these patients before and after oral corticosteroid therapy in collaboration with the pediatrics department.

RESULTS

After a mean of 1.8 ± 0.7 days of oral steroid treatment, eyelid edema, corneal damage, conjunctival injection, follicles, and chemosis improved in all patients.

CONCLUSIONS

Oral steroids are an effective adjuvant treatment for EKC in patients younger than 3 years in whom eye drops could not be administered frequently due to severe eyelid edema.

Epidemic keratoconjunctivitis: the current situation and recommendations for prevention and treatment

BACKGROUND

Epidemic keratoconjunctivitis (EKC) is a highly contagious infection of the ocular surface. 316 cases were diagnosed in Germany in the first 8 months of 2010, corresponding to a 300% increase above the typical figures for recent years. This outbreak motivates us to present the current recommendations concerning EKC.

METHODS

Selective literature review.

RESULTS

EKC is an adenoviral infection that typically starts with a unilateral foreign body sensation and then develops, within a few hours or days, into bilateral keratoconjunctivitis with marked chemosis, epiphora, and photophobia. Visual impairment can persist for months because of subepithelial corneal infiltrates (nummuli) and irregular astigmatism. Randomized clinical trials have not shown any clear benefit in the acute phase from any of a variety of treatments, including steroids, calcineurin inhibitors, virostatic drugs and disinfecting agents. In the chronic phase, cyclosporin A eye drops can accelerate the regression of subepithelial infiltrates. Hygienic measures, including conscientious hand and surface disinfection, can lessen the spread of the disease.

CONCLUSION

The first priority in the treatment of patients with definite or suspected EKC is the rigorous application of hygienic measures in medical facilities, particularly because there is still no effective drug treatment for this disease. No virostatic agent has yet been demonstrated to influence its course, either subjectively or objectively.

Adenoviral keratoconjunctivitis

Acute epibulbar infections in humans are one of the most frequently diagnosed eye diseases. The majority of these are thought to be caused by the adenovirus. This review focuses on the features of the human adenovirus eye diseases, mode of transmission, signs and symptoms, available interventions, and preventive measures. It is concluded that infection control is still widely accepted to be the key to the management of human adenovirus infection in order to prevent the spread, individual suffering and economic damage.

Adenoviruses in the immunocompromised host

Adenoviruses are among the many pathogens and opportunistic agents that cause serious infection in the congenitally immunocompromised, in patients undergoing immunosuppressive treatment for organ and tissue transplants and for cancers, and in human immunodeficiency virus-infected patients. Adenovirus infections in these patients tend to become disseminated and severe, and the serotypes involved are clustered according to the age of the patient and the nature of the immunosuppression. Over 300 adenovirus infections in immunocompromised patients, with an overall case fatality rate of 48%, are reviewed in this paper. Children with severe combined immunodeficiency syndrome and other primary immunodeficiencies are exposed to the serotypes of subgroups B and C that commonly infect young children, and thus their infections are due to types 1 to 7 and 31 of subgenus A. Children with bone marrow and liver transplants often have lung and liver adenovirus infections that are due to an expanded set of subgenus A, B, C, and E serotypes. Adults with kidney transplants have viruses of subgenus B, mostly types 11, 34, and 35, which cause cystitis. This review indicates that 11% of transplant recipients become infected with adenoviruses, with case fatality rates from 60% for bone marrow transplant patients to 18% for renal transplant patients. Patients with AIDS become infected with a diversity of serotypes of all subgenera because their adult age and life-style expose them to many adenoviruses, possibly resulting in antigenically intermediate strains that are not found elsewhere. Interestingly, isolates from the urine of AIDS patients are generally of subgenus B and comprise types 11, 21, 34, 35, and intermediate strains of these types, whereas isolates from stool are of subgenus D and comprise many rare, new, and intermediate strains that are untypeable for practical purposes. It has been estimated that adenoviruses cause active infection in 12% of AIDS patients and that 45% of these infections terminate in death within 2 months. In all immunocompromised patients, generalized illness involving the central nervous system, respiratory system, hepatitis, and gastroenteritis usually have a fulminant course and result in death. Treatments for adenovirus infections are of little proven value, although certain purine and pyrimidine analogs have shown beneficial effects in vitro and may be promising drugs.

Inhibitory effect of (S)-HPMPC, (S)-HPMPA, and 2'-nor-cyclic GMP on clinical ocular adenoviral isolates is serotype-dependent in vitro

Currently, there is no effective treatment for ocular adenoviral infections that occur in epidemics worldwide, produce significant patient morbidity, and cause substantial economic losses. We tested several new antivirals in vitro, and found that (S)-HPMPC, (S)-HPMPA, and 2'-nor-cyclic GMP demonstrated significant serotype-dependent inhibitory activity by plaque reduction assay (ID50 = 0.017-17.0 micrograms/ml) against common clinical ocular isolates and standard adenoviral serotypes (Ad 1, Ad 5, Ad 8, and Ad 19). (S)-HPMPC was the least toxic (CD50 in A549 cells = 306 micrograms/ml), and (S)-HPMPC and (S)-HPMPA had high selectivity indices.

Molecular epidemiology of two consecutive outbreaks of adenovirus 8 keratoconjunctivitis

Eleven strains of adenovirus 8 (Ad 8) isolated during two consecutive outbreaks of epidemic keratoconjunctivitis (EKC) in the Ophthalmology Department of a University Hospital in France were compared by DNA restriction analysis. The results indicated that isolates from the two outbreaks belong to the same genome type, which is also the most predominant genome type of Ad 8. The usefulness of molecular epidemiology in Ad 8 infections is briefly discussed.

Topical human fibroblast interferon for acute adenoviral conjunctivitis

We conducted a prospective, randomized, double-blind, placebo-controlled clinical trial investigating the use of topical human fibroblast interferon (HuIFN-beta) 7.5 x 10(5) IU/ml, one drop 5 times daily, in the treatment of acute epidemic conjunctivitis. Of 50 patients who were initially enrolled, tear-film cultures for adenovirus were positive from 26% for type 8, 12, or 19. Based upon a quantifiable conjunctivitis severity score of 37 patients evaluated after approximately 1 week of therapy, analysis of covariance showed a statistically significant greater improvement with topical HuIFN-beta compared with placebo for affected left eyes (P = 0.02) but not for right eyes (P = 0.5), an effect that could not be adequately explained. We suggest that a higher dosage of topical HuIFN-beta may prove useful in the control of more severely affected cases. This trial provides guidelines for future investigations of interferon in the treatment and prophylaxis of adenoviral keratoconjunctivitis.

Evaluation of a commercial monoclonal antibody for detection of adenovirus antigen

The Adenoclone monoclonal antibody for detection of adenovirus antigen was evaluated by enzyme immunoassay and a 72-h indirect fluorescent-antibody test in shell vials and compared with standard culture. The sensitivity and specificity of the Adenoclone test were both 100% with 114 cell culture isolates. With 310 direct clinical specimens, the Adenoclone enzyme immunoassay sensitivity varied from 14.3 to 66.6%, but the Adenoclone indirect fluorescent-antibody test sensitivity was 86.7%, with 100% specificity.