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Abstract: Three α-herpesviruses are known to be associated with central nervous system (CNS) infection; however, there are limited data on the incidence and clinical characteristics of α-herpesviruses CNS infections. This study aimed to assess the clinical manifestations, laboratory findings, and outcomes in patients with human herpes simplex virus 1 (HSV-1), human herpes simplex virus 2 (HSV-2), and varicella-zoster virus (VZV) CNS infections.We identified cases of HSV-1, HSV-2, and VZV CNS infections and reviewed their clinical and laboratory characteristics. The study population was drawn from patients with HSV-1, HSV-2, and VZV polymerase chain reaction positivity in cerebrospinal fluid (CSF) who visited Pusan National University Hospital between 2010 and 2018.During the 9-year study period, a total of 727 CSF samples were examined, with 72.2% (525/727) patients identified as having a CNS infection. Of 471 patients with aseptic meningitis and encephalitis, the causative virus was identified in 145 patients, and no virus was detected in 337 patients. A total of 15.2% (80/525) were diagnosed with one of the 3 herpesviruses as causative agents, 59 patients had meningitis, and 21 patients had encephalitis. Eleven patients with HSV-1, 27 patients with HSV-2, and 42 patients with VZV CNS infections were included. The distribution of cases by age showed different patterns depending on the type of herpesvirus infection. Compared with the HSV-1 group, the median age in the HSV-2 group was younger (HSV-1: 58 years; HSV-2: 38 years; P = .004), and patients with VZV infections showed a bimodal age distribution. Encephalitis was more common in the HSV-1 group, and HSV-1 infection was associated with a poor prognosis at discharge. CSF white blood cell counts were significantly lower in patients infected with HSV-1 (117 × 106 cells/L) than in patients infected with VZV (301 × 106 cells/L) (P = .008).These 3 herpesviruses are important causes of CNS infections regardless of immunologic status. HSV-1 infection was commonly associated with encephalitis and poor prognosis; HSV-2 and VZV CNS infections were associated with a low risk of mortality and neurological sequelae., Competing Interests: The authors have no funding and conflicts of interest to disclose., (Copyright © 2021 the Author(s). Published by Wolters Kluwer Health, Inc.)

Neonatal herpes simplex virus infection (HSV) is rare in neonates, with an estimated global incidence of 10 per 100,000 live births. Neonatal HSV is challenging to diagnose due to often vague signs and symptoms. Untreated, the mortality of some HSV subtypes exceeds 80%. Overtesting and overtreatment can result in prolonged hospitalizations and expose neonates to medication toxicity. In contrast, prompt evaluation and use of empiric antiviral therapy before the results of definitive testing can improve outcomes for infants with HSV. A wide degree of practice variation exists with respect to testing and treatment for neonatal HSV, and more research is required to safely risk-stratify this population. This review presents the epidemiology, risk factors, presenting features, and emergency department management of neonatal HSV infection.

Background: Lesions of herpes labialis are caused by the herpes simplex virus type 1 and cause pain and aesthetic compromise. It is characterized by the formation of small vesicles that coalesce and rupture forming extremely painful ulcers, that evolve to crusts, dry desquamations until their complete remission. Currently the treatment of these lesions is done with acyclovir. Although it diminishes the symptomatology, it causes viral resistance and does not prevent the recurrence of the lesions. It is known that antimicrobial photodynamic therapy (aPDT) has numerous advantages, among them: the reduction of the time of remission, and does not cause resistance. This protocol will determine the effectiveness of PDT in lesions of herpes labialis., Materials and Methods: A total of 30 patients with herpes labialis in the prodromal stage of vesicles, ulcers, and crusts will be selected to participate in the study and randomized into 2 groups: G1 control and G2 experimental. After signing Research Ethics Committee and TA, patients in group G1 will undergo the standard gold treatment for herpes labialis with acyclovir and simulated PDT treatment. Patients in the experimental G2 group will be treated simulating the gold standard treatment of herpes labialis (placebo) and PDT. In all patients, saliva samples will be collected for analysis of cytokines, and will be performed exfoliative cytology in the lesions. The pain will be assessed through a pain scale and a questionnaire of quality of life related to oral health (OHIP-14) will be given to them. Patients will continue to be followed up after 7 days, 1 month, 3 months, and 6 months; if there is a recurrence of the lesion, they will contact the researchers.Clinical registration: clinicaltrials.gov - NCT04037475. Registered on July 2019.

Purpose: To investigate the clinical characteristics and visual outcome of bilateral acute retinal necrosis., Methods: The study included 30 patients (60 eyes) who were diagnosed with bilateral acute retinal necrosis. The medical records were reviewed., Results: Twenty-five patients developed the disease in the contralateral eye within 5 months and 5 patients at >2 years after the initial onset. At presentation, 14 of 21 eyes suffered from retinal necrosis of more than 180° in the initially affected eye, whereas 3 of 22 eyes suffered it in the later-affected eye. Retinal detachment occurred in 23 of the 27 initially affected eyes and in 5 of the 27 later-affected eyes. The mean logarithm of the minimum angle of resolution best-corrected visual acuity decreased from 2.0 ± 1.1 (Snellen equivalent counting fingers) to 2.2 ± 1.0 (Snellen equivalent counting fingers) in the initially affected eyes after a follow-up of 34.1 ± 48.2 months (P = 0.529), and improved from 0.5 ± 0.4 (Snellen equivalent 20/66) to 0.3 ± 0.4 (Snellen equivalent 20/40) in the later-affected eyes after a follow-up of 21.2 ± 23.3 months (P = 0.005)., Conclusion: Bilateral acute retinal necrosis usually occurs in the contralateral eye within a few months, but sometimes after several years. Inflammation and retinal necrosis are less severe in the later-affected eye, with less retinal detachment and a better visual outcome.

Purpose: To analyze the clinical presentation, characteristics, treatment, recurrences, and final outcomes and complications of herpes simplex virus (HSV) disease of the anterior segment in patients aged 17 years or younger., Methods: This is an observational and retrospective study with review of the medical records of all the children diagnosed with herpes simplex infection of the anterior segment at an ophthalmologic referral center, from 2002 to 2012. The diagnosis was made on the basis of the history and examination of patients and in specific cases by viral culture and the polymerase chain reaction. Main outcome measurements included final visual acuity, bilateral disease, and recurrence. Recurrent disease was analyzed with Kaplan-Meier curves., Results: A total of 103 patients were included with a median age at presentation of 9 years. Of them, 6 had bilateral and simultaneous disease. The median follow-up time was 18 months (range, 18 days-12 years). The most common clinical manifestations were epithelial dendritic keratitis in 42 eyes (38.5%) and interstitial keratitis in 39 eyes (35.7%), with 15 patients presenting multiple forms of HSV disease. The median final visual acuity in the group of patients was 20/40. Recurrent disease was evident in 42 (38.5%) of the eyes, with a median recurrence time of 15 months (95% confidence interval, 8.1-26.2 months)., Conclusions: In this study, epithelial dendritic and interstitial keratitis were the most frequent forms of disease in the pediatric population with HSV of the anterior segment. A high rate of recurrent disease was present.

A woman with severe and longstanding systemic lupus erythematosus presented with a 1-week history of fever up to 38°C and pain in her right flank. Computed tomography scan of the chest revealed interstitial infiltrates and multiple nodules. Bronchoalveolar lavage did not show any inflammatory cells. Gram stain and cultures for aerobic and anaerobic bacteria, fungi, and Nocardia; acid-fast staining; polymerase chain reaction for tuberculosis, cytomegalovirus, herpesvirus 6, and parvovirus B19; and IF staining for pneumocystic and Legionella antigen were all negative. Transbronchial biopsy was nondiagnostic. Open lung biopsy with polymerase chain reaction and immunohistochemistry analyses revealed herpes simplex virus 1 infection. Acyclovir therapy was initiated and was followed by significant improvement. Herpes simplex virus 1 infection (although unusual) should be considered in patients with systemic lupus erythematosus with an atypical clinical presentation.

Purpose: To determine the prevalence of herpes simplex virus type 1 (HSV-1) DNA in failed Descemet membrane stripping automated endothelial keratoplasty (DSAEK) grafts., Methods: A retrospective interventional case series of patients with DSAEK graft failure treated at the New York Eye and Ear Infirmary between January 2009 and July 2012 was performed. Repeat DSAEK, penetrating keratoplasty, or keratoprosthesis procedure was subsequently performed on eyes with failed grafts. All failed grafts were examined immunohistochemically and with qualitative real-time polymerase chain reaction for HSV-1 DNA. In HSV-1-positive cases, corneoscleral donor rims from the original DSAEK procedures were also examined immunohistochemically and with polymerase chain reaction., Results: Fifty-one failed DSAEK grafts from 50 eyes of 49 patients were identified. Indications for DSAEK were pseudophakic bullous keratopathy (28/51, 55%), Fuchs corneal endothelial dystrophy (12/51, 23%), failed penetrating keratoplasty (7/51, 14%), corneal decompensation from glaucoma (2/51, 4%), herpetic endotheliitis (1/51, 2%), and failed DSAEK (1/51, 2%). Forty-three grafts (83%) were primary DSAEK graft failure. HSV-1 DNA was isolated from 2 of 51 failed DSAEK grafts (4.0%). The corresponding corneoscleral donor rims did not demonstrate the presence of HSV-1., Conclusions: Based on our results, HSV-1 infection plays a minor role in DSAEK graft failure. The data suggest that recipient reactivation, rather than donor transmission, plays a role in HSV infection.

Purpose of Review: To summarize the articles published in 2012 pertaining to the clinical presentation, diagnosis, and treatment of herpetic keratitis, with specific attention to pediatric population., Recent Findings: Liu et al. confirm prior literature that herpetic keratitis has higher recurrence rate in children than adults. Recurrences are more likely to occur as stromal disease. Vision loss in children is from corneal scarring leading to deprivation and/or refractive amblyopia. Acyclovir is safe and well tolerated as a treatment in pediatric population, and preferable to difficult and toxic eye-drop regimens.Immunochromatographic assay is an effective diagnostic tool to confirm diagnosis of herpes simplex virus-1 (HSV) in corneal scrapings with high specificity but poorer sensitivity.Real time PCR can be employed to follow changes in HSV viral load in patients where resistance is suspected., Summary: Delays in treatment related to misdiagnosis, as well as resistance to current antiviral therapeutics, can lead to visually devastating corneal opacification. In the pediatric population, already at risk for amblyopia, this can be especially damaging. Children are unique with regards to the way in which they manifest herpetic keratitis, making rapid diagnosis and treatment even more challenging.

Herpes simplex virus type 1 (HSV-1) establishes a latent infection in sensory neurons that can sometimes be reactivated. HSV-1 keratitis often recurs and can be vision threatening. Reactivation of the latent virus can be stimulated by stress, immunosuppression, trauma, adrenergic iontophoresis, and UV radiation. Healthy and asymptomatic individuals are known to shed HSV-1, and this is a major factor in the spread of the virus. We investigated the frequency of shedding of HSV-1 DNA in tears of dry eye patients and individuals with conjunctivitis. Subjects were divided into 3 groups: normal (12 eyes), dry eye (11 eyes), and conjunctivitis (15 eyes). Quantitative real-time polymerase chain reaction was used for HSV DNA detection. The incidences of HSV positivity in the normal, dry eye, and conjunctivitis groups were 1 of 12 (8.3%), 3 of 11 (27.3%), and 4 of 15 (26.7%), respectively. We have previously shown that bromfenac sodium eye drops, intramuscular adenosine monophosphate, and geldanamycin effectively lower HSV-1 recurrence rates in a mouse model. Recently, we also found that nuclear factor κ-B, an IκB kinase-β inhibitor, could be a candidate for reducing HSV-1 reactivation. We sampled recipients' corneal buttons during keratoplasty and performed polymerase chain reaction. Cytomegalovirus (CMV) DNA was detected in corneas obtained from some patients, and the copy number of the detected CMV DNA was quantified. CMV DNA-positive samples were taken from 2 of the 3 patients with ocular pemphigoid; thus, in future work, the relationship between CMV in the cornea and the incidence/onset of ocular diseases of the anterior segment needs to be evaluated.

Purpose: : The purpose of this study was to determine the association of human herpes virus 6 (HHV-6) and/or other human herpesviruses in corneal inflammation using polymerase chain reaction (PCR)., Methods: : We collected tear films, conjunctival smears, and a corneal button of inflamed cornea, and the presence of HHV-6 and other herpesviruses in these samples were assessed by a nested PCR., Results: : In tear films collected from 3 of 9 patients with dendritic keratitis, HHV-6 DNA was positive twice, together with herpes simplex virus (HSV) or varicella zoster virus DNA most often, during the acute phase of the disease. Two other patients in this group were either positive for HSV-1 and varicella zoster virus or for HSV-1 and Epstein-Barr virus DNA but negative for HHV-6. When another 12 patients' smear samples from corneal ulcer or keratouveitis were examined, 9 were positive for HHV-6 DNA. Of these, 4 were positive for HSV-1 simultaneously, whereas the remaining 5 patients were negative for HSV-1. One patient's smear was positive for HSV-1 but not for HHV-6. In the corneal button, both HSV and HHV-6 DNAs were positive by nested PCR. HHV-6 was also positive by nested PCR in the conjunctival swab obtained from the contralateral inflamed eye of the patient., Conclusions: : In 22 patients with corneal inflammation, HHV-6 was positive in 14 of 22 patients and HSV-1 was found in 9 of those patients. These data indicated that the association of HHV-6 with disease was more frequent than with other herpesviruses and that HHV-6 may be another sole causative agent for corneal inflammation.

Aims: To characterise the epidemiology of anogenital herpes in Melbourne by detailing the age-specific prevalence of herpes simplex virus (HSV) 1 and HSV 2., Methods: A cross-sectional study of 2055 anogenital specimens assayed by polymerase chain reaction (PCR) for HSV 1 and 2 at Melbourne Pathology from 1 August 2004 to 11 May 2005 was conducted. Results were analysed by age and sex., Results: PCR demonstrated HSV 1 in 44.1% of all anogenital herpes cases. The relative prevalence of HSV 1 decreased as a function of increasing age. In patients under the age of 20, 18.2% of cases of anogenital herpes were due to HSV 2, as compared with 84.6% in patients over the age of 50., Conclusions: In this study population a clear relationship is seen between age and relative frequency of HSV 1 and 2 as a cause of anogenital herpes. HSV 2 accounts for only a small proportion of infections in younger patients.

Purpose: We detected herpes simplex virus types 1 (HSV-1) and 2 (HSV-2), varicella zoster virus (VZV), and cytomegalovirus (CMV) DNAs in recipient corneal buttons taken at the time of penetrating keratoplasty., Methods: Twenty-seven corneal buttons were obtained from 27 patients (10 men and 17 women), 7 of whom had a history of HSV keratitis. Excised corneal buttons were immediately frozen in liquid nitrogen in the operating theater and then stored at -80°C until DNA extraction. The detection of HSV-1, HSV-2, VZV, and CMV DNAs was carried out by a nested polymerase chain reaction (PCR) method. The genome copy numbers for the nested PCR-positive samples were subsequently quantified by real-time PCR., Results: HSV-1, HSV-2, VZV, and CMV DNAs were detected in 10, 1, 9, and 2 of the 27 recipient corneal buttons, respectively. HSV-1 or HSV-2 DNAs were also detected in 5 of 7 patients with a history of HSV keratitis. Both CMV-positive patients (patients 2 and 3) had ocular pemphigoid. Among the nested PCR-positive samples, 2 HSV-1, 1 HSV-2, 1 VZV, and 1 CMV sample could be quantified by real-time PCR. Copy numbers ranged from 19 to 928 copies., Conclusions: All 4 herpesviruses, including CMV, were detected in the corneal buttons. The relationship between CMV in the cornea and ocular diseases of the anterior segment should be further evaluated.

The authors present a case of environmentally acquired fatal herpes virus type I infection in a newborn after cesarean section and a discussion of the clinical presentation, pathogenesis and diagnosis of herpes simplex type I (HSV-1) at autopsy. Herpes simplex virus, both type I and type II, are well described infectious agents in newborns. Though herpes simplex type II (HSV-2) is commonly associated with fatal neonatal infections, it is important to consider HSV-1 to make the correct diagnosis. Additionally, although HSV infections are typically acquired during parturition, it is possible to be infected postpartum from the environment as occurred in this case. The diagnosis of neonatal HSV must also be communicated by the forensic pathologist to applicable healthcare providers and health care facilities, because of public health and medicolegal issues.

Summary: Although the standard of care in febrile neutropenic patients includes the initiation of empirical antibacterial and antifungal therapy, many patients do not respond and need further diagnostic work up and treatment. Here, we report on an immunosuppressed neutropenic patient with a prolonged episode of fever unresponsive to empirical antibacterial therapy. Herpes polymerase chain reaction revealed systemic reactivation of herpes simplex virus type 1 (HSV-1) infection and treatment with acyclovir was associated with the prompt resolution of signs and symptoms of infection. Screening for HSV in persistently febrile neutropenic patients may discover HSV reactivation that can be treated successfully by acyclovir administration.

Purpose: To characterize confocal scan features of keratic precipitates (KPs) in Fuchs heterochromic iridocyclitis., Methods: Confocal scans of KPs in patients with Fuchs uveitis were performed. Polymerase chain reaction technique of aqueous for herpes simplex, herpes zoster, Toxoplasma, cytomegalovirus, and rubella was performed for 4 patients., Results: Confocal scan was performed in 40 eyes of 34 patients [18 males and 16 females, mean age 30.7 +/- 10.5 years (range 18-57 years)]. Fuchs heterochromic iridocyclitis was bilateral in 6 and unilateral in 28 patients. All eyes had KPs: globular KPs were found in 34 eyes, infiltrating and dendritiform in 31 eyes, stippled in 27 eyes, and cruciform in 19 eyes. Polymerase chain reaction of aqueous specimens for the above-mentioned infectious agents was negative in 4 eyes of 4 individuals who had infiltrating and dendritiform KPs on confocal scan, with no other concurrent disorder., Conclusions: Confocal features of KPs in Fuchs uveitis are diverse. The presence of dendritiform and infiltrating KPs on confocal scan may not be suggestive of an infectious etiology.

Methods: We examined the cross-sectional relationships of subclinical atherosclerosis - expressed by carotid intimal-medial thickness and coronary calcification - with antibodies to Chlamydia pneumoniae, Helicobacter pylori, cytomegalovirus, herpes simplex virus, hepatitis A virus, and pathogen burden (number of positive pathogens). A random sample of 1056 individuals chosen from 5030 Multi-Ethnic Study of Atherosclerosis cohort participants were included., Results: After multiple adjustment, no associations were found between atherosclerosis measures and either individual pathogens or pathogen burden. Interactions with inflammatory and endothelial function markers, demographic factors, BMI, high-density lipoprotein, diabetes, and smoking were also explored. The only interaction that was large, qualitative, statistically significant (P < 0.05) and in the expected direction was that between hepatitis A virus and soluble intercellular adhesion molecule-1 with regard to Agatston calcium score: the difference between hepatitis A virus-positive and hepatitis A virus-negative participants was -186 units in participants with soluble intercellular adhesion molecule-1 below the median, and +162 units in those with soluble intercellular adhesion molecule-1 equal or above the median. However, given the number of interactions that were explored, these results must be interpreted cautiously., Conclusion: Findings from the present analyses do not provide support for an infectious etiology for subclinical atherosclerosis. However, the study's limitations, which include its cross-sectional design and insufficient statistical power, suggest that inferences from its findings should be made cautiously.

Purpose: To report a case of herpetic epithelial keratitis that developed after intravitreal bevacizumab (Avastin) injection., Methods: A 63-year-old man with diabetes with proliferative diabetic retinopathy and macular edema received intravitreal injection of bevacizumab (Avastin) in his right eye., Results: Three days after the injection, the patient presented with foreign body sensation, redness, tearing, photophobia, and decreased visual acuity in the right eye. The cornea showed an arborizing dendritic epithelial lesion with terminal bulb typical of herpes simplex virus (HSV) epithelial keratitis. HSV-DNA was detected in corneal scrapings using polymerase chain reaction. A diagnosis for herpes simplex epithelial keratitis was made. Topical acyclovir ointment therapy was initiated with good resolution of HSV signs and symptoms., Conclusions: Herpes simplex epithelial keratitis can be a possible complication of intravitreal bevacizumab (Avastin) injection. To our knowledge, this case is the first report of herpetic epithelial keratitis after intravitreal bevacizumab (Avastin) injection.

Purpose: To report the clinical characteristics and visual outcomes of pediatric herpes simplex virus (HSV) keratitis., Methods: The medical records of 29 patients younger than 16 years with HSV keratitis who were diagnosed and treated at Chang Gung Memorial Hospital, Taoyuan, Taiwan, between 1996 and 2004 were retrospectively reviewed. The diagnosis of HSV keratitis was proven by a positive viral culture and/or real-time quantitative polymerase chain reaction or by a clear history of dendritic keratitis or herpetic kerato-uveitis. Type of HSV keratitis, recurrence rate, and visual outcome were analyzed., Results: The average age at the entry into the study was 5.7 years (range: 7 months to 15 years). Mean follow-up time was 35.3 months (range: 2-69 months). Epithelial keratitis including dendritic and geographic ulcers was noted in 14 eyes, stromal keratitis in 2 eyes, stromal keratitis concurrent with epithelial keratitis in 8 eyes, and endotheliitis in 6 eyes. One patient had sequential involvement of both eyes. Thirteen patients (45%) developed recurrent HSV keratitis after the first documented episode. Female gender (but not age or the type of keratitis) was significantly associated with recurrences. Five patients who were maintained on oral valacyclovir prophylaxis up to 1 year had no recurrence during the period. Fifteen of 21 patients younger than 8 years of age had best-corrected visual acuity available at last follow-up, and 10 patients developed amblyopia., Conclusions: Children with HSV keratitis are at risk for recurrent keratitis and amblyopia. Prolonged systemic antiviral prophylaxis may help to prevent such consequences.

Purpose: To evaluate the presence of herpes simplex virus (HSV) in pterygia to study the possible association between HSV and pterygia in Taiwan, a tropical country with a high prevalence of pterygium., Methods: Sixty-five pterygia, 10 normal conjunctiva, 8 conjunctival nevi, and 2 malignant conjunctival melanomas were obtained. Clinical histories were recorded for each patient. HSV detection was accomplished by polymerase chain reaction amplification of viral sequences. HSV-positive specimens underwent subsequent DNA in situ hybridization. Results were statistically analyzed., Results: By using polymerase chain reaction, HSV was detected in 3 (5%) pterygia, and no conjunctival control displayed HSV. All 3 HSV-positive pterygia studies were DNA in situ hybridization negative. There was no statistically significant correlation between pterygium and the presence of HSV., Conclusions: HSV is not associated with pterygium formation in Taiwan; the pathogenesis of pterygia is still incompletely understood.

Purpose: To detect herpes simplex virus (HSV) genome in the cornea, we sampled the limbal corneas and scleras of the imported eye bank eyes and recipient's corneal buttons and quantitated HSV genome in them by real-time polymerase chain reaction (PCR)., Methods: Forty-four recipient corneas including 7 corneas with and 37 corneas without a history of herpetic keratitis, 70 eye bank donor limbal corneas, and 35 eye bank donor scleras were obtained. Primers for real-time PCR were synthesized using the HSV-1 and -2 common regions of the viral DNA polymerase. Primers for conventional PCR were designed to detect HSV-1 and -2 and varicella zoster virus (VZV)., Results: Significantly higher copy number of HSV DNA was detected in corneas with a history of herpetic keratitis 85.7% (6/7), with an average of 1.6 x 10(4) copies/mg tissue weight than in corneas without a history of herpetic keratitis 10.8% (4/37), with an average of 8.7 copies/mg tissue weight (P < 0.05, Mann-Whitney U test). HSV DNA was detected in 5.7% (4/70) of the eye bank donor corneas, with an average of 4.9 x 10(2) copies/mg tissue weight, and in 8.6% (3/35) of the donor scleras, with an average of 10.6 copies/mg tissue weight. HSV-2 and VZV-DNA were not detected in these samples., Conclusions: Real-time PCR quantitated HSV genome in the cornea even at a quiescent phase of infection. HSV genome was detected in the corneas and scleras without a past history of herpetic keratitis by this method.

Purpose: To introduce into the clinical nomenclature a sign frequently observed in our patients with persistent corneal inflammation associated with herpetic stromal keratitis., Methods: Case reports and review of the literature., Results: Four representative patients with herpesvirus stromal keratitis are presented. Herpes simplex virus-1 (HSV-1) was confirmed by culture in 1 case and by polymerase chain reaction in a second case. In the remaining 2 cases, the diagnosis was made based on characteristic clinical findings for herpes simplex virus and varicella zoster virus (VZV). On clinical examination, all 4 representative cases of stromal keratitis revealed a well-defined, localized region of intertwined, metallic-like, polychromatic material in the corneal stroma, a sign we have termed steel wool keratopathy. We have only rarely observed this finding in patients with stromal keratitis not caused by a herpesvirus., Conclusion: Steel wool keratopathy seems to represent a focal region of stromal degeneration or deposition associated with chronic inflammation. Although we most often observe this finding in patients with stromal keratitis secondary to HSV or VZV, we cannot exclude the possibility that this sign represents the sequelae of chronic/recurrent inflammation rather than a specific pathologic response to herpetic antigens.

Background: Acute liver failure (ALF) in neonates is rare but carries a high mortality without liver transplantation. Herpes simplex virus (HSV) is one of the microbes that more commonly causes ALF and is potentially treatable; hence, early diagnosis and treatment are important to avoid progression to liver failure., Patients and Results: We have analysed retrospectively the case notes of 11 patients with HSV-induced ALF. A history of possible herpes infection was elicited in 5 parents, but HSV had not been suspected clinically. All patients were asymptomatic when discharged from postnatal units and were presented with nonspecific symptoms of poor feeding and lethargy within 2 weeks from birth. Seven of the 11 patients had HSV-1 infection, 4 HSV-2. Only 2 patients who received early treatment with intravenous acyclovir survived., Conclusions: HSV-related ALF in the neonatal period carries high morbidity and mortality and needs a high index of suspicion so that life-saving treatment can be started promptly. Both HSV-1 and HSV-2 can cause severe neonatal infection. It is important to recognise HSV infection in women of childbearing age and their sexual partners.

Objectives: The objectives of this study were to study the role of herpes virus reactivation in the onset of delayed facial paralysis (DFP) occurring more than 72 hours after vestibular schwannoma (VS) surgery and to advocate specific medical management., Study Design: We conducted a retrospective case review., Setting: University-based, tertiary care center., Patients: Eight patients managed for DFP in a series of 348 patients operated for a VS., Interventions: Patients were evaluated and graded according to the House and Brackmann grading system and followed up for 1 year. A serologic search for specific antiherpes simplex viruses type 1 and 2 (HSV-2) and varicella zoster virus (VZV) antibodies at the onset of DFP and 2 weeks later was possible in three cases. Seven of the eight patients were given intravenous acyclovir (30 mg/kg/ for 5 days) and methylprednisolone (2 mg.kg/ for 7 days)., Results: Mean delay of DFP onset was 8.75 days. All treated patients had a House and Brackmann Grade 1 recovery: mean time to recovery was 40.4 days. The last one had only a Grade 3 recovery because he could not be treated because of postoperative transient psychiatric problems. Serologic testing in those patients in whom it could be done revealed either a high level of anti HSV or VZV antibodies at the time of onset or a dramatic increase in anti-HSV or anti-VZV antibodies between the two samples, strongly suggesting an HSV or VZV reactivation., Conclusion: HSV or VZV reactivation might be responsible for most cases of DFPs, thus suggesting the usefulness of immediate steroid and acyclovir administration to obtain total recovery. The viral reactivation mechanism is comparable to that already suspected in DFP occurring with the same delay in middle ear surgical procedures.

Objective: To report recurrent herpetic keratouveitis following YAG laser peripheral iridotomy., Methods: Case report., Results: A 64-year-old woman with a history of dendritic keratitis underwent Nd:YAG laser peripheral iridotomy and developed geographic epithelial keratitis with stromal keratouveitis. Culture of a corneal swab grew herpes simplex virus type I. Keratouveitis subsided with acyclovir and corticosteroid therapy., Conclusions: Recurrent herpetic keratouveitis may be induced by YAG laser iridotomy.

Objective: To report three cases of herpetic infection in recipients of organ-cultured donor corneas among 586 consecutive corneal transplantation procedures., Methods: Three patients with no history of symptomatic herpes infection underwent corneal transplantation for keratoconus (2 patients) and Fuchs dystrophy (1 patient). Two patients developed keratouveitis and primary graft failure. The third patient developed dendritic keratitis in the graft. Culture of corneal scrapings and the patient's bandage contact lens were positive for herpes simplex virus type 1 (HSV-1). Donor and recipient sera were tested for HSV serology by EIA. Recipient corneal buttons were studied by means of transmission electron microscopy and immunohistochemistry. The three HSV-1 strains were genotyped by sequencing part of a variable antigenic domain of glycoprotein B (gB)., Results: None of the donor corneas showed endothelial cell necrosis after organ culture. All keratoplasties performed with the three mate donor corneas had an uncomplicated course. All three donor sera were positive for HSV. Preoperative recipient sera were positive for HSV. Analysis of the recipient corneal buttons showed no evidence of herpetic infection. Sequence analysis revealed three different gB genotypes., Conclusion: Ascertaining that a postoperative herpetic infection in a corneal transplant originates from the donor tissue is still difficult. Although some features of the reported cases suggest donor-to-host transmission of herpes simplex virus, the recipients could have been the source of the virus.

The authors report a fatal outcome in a 4-year-old boy with herpes simplex virus (HSV) pneumonia and ependymoma. The patient had respiratory distress that worsened despite antibiotic treatment. Bronchoalveolar lavage showed intranuclear viral inclusions, and culture was positive for HSV type 1. His T-cell count was significantly decreased. Although acyclovir and foscarnet were given, the patient died. Postmortem examination showed HSV pneumonitis with severe alveolar damage and severe involutional changes of the thymus with absence of Hassall's corpuscles. HSV must be considered in the differential diagnosis of patients with interstitial pneumonia and T-cell deficiency, especially after craniospinal irradiation.

Unlabelled: PURPOSE The purpose of this analysis was to determine whether present National Federation of State High School Associations (NFHS) guidelines adequately prevent and control outbreaks of primary herpes gladiatorum (HG) in high-school wrestlers., Methods: Using telephone interviews, direct physical examinations, and review of medical charts, data were collected on HG outbreaks among participating teams in the 1999 Minnesota State High School League (MSHSL) wrestling season and on HG outbreaks for 3 yr at a 28-d summer wrestling camp., Results: The outbreak during the 1999 MSHSL wrestling season involved 61 wrestlers and three coaches on 19 teams over 42 d, with a 32.7% probability of transmission to sparring partners. Typical length of time from exposure to outbreak varied from 4 to 11 d with an average of 6.80 +/- 1.70 d. Analysis of data from three outbreaks at a 28-d wrestling camp showed that most outbreaks (96%) occurred on the ventral surface of the body, with 71.9% on the head, face, and neck, areas in direct contact when wrestlers are engaged in the lock-up position. Analysis of data from the 2001 camp outbreak showed that the locations of the lesions reflected the handedness of the wrestler., Conclusion: The NFHS guidelines are inadequate to prevent and control outbreaks of HG. The focus of preventive efforts needs to change from mat cleanliness to more rapid detection of outbreaks by requiring culture results and appropriate therapy for all suspected bacterial and herpes lesions before allowing return to contact. To minimize and control spread of HG, treatment and isolation should be implemented based not only on vesicle formation but also on systemic signs and symptoms.

Viral and bacterial infectious agents have been implicated in the etiology of atherosclerosis. We have previously shown that a gamma-herpesvirus can accelerate atherosclerosis in the apolipoprotein E-deficient (apoE-/-) mouse. To address whether a virally induced systemic immune response is sufficient to trigger enhanced atheroma formation, we infected apoE-/- mice with murine gamma-herpesvirus-68 (MHV-68) or herpes simplex virus-1 (HSV-1). In this study, we show that both viruses were able to induce a cell-mediated and humoral immune response in the apoE-/- mouse, which was sustained over a period of 24 weeks. Although intranasal or intraperitoneal infection with MHV-68 induced similar levels of virus-specific IgG1 and IgG2a antibodies in the serum of apoE-/- mice, those infected with HSV-1 showed higher anti-HSV-1 IgG2a compared with IgG1 antibody levels. In addition, viral message was not detected in the aortas of HSV-1-infected animals, whereas we have shown previously that MHV-68 mRNA can be detected in the aortas of infected mice as early as 5 days after infection. Compared with control mice, apoE-/- mice infected with MHV-68 showed accelerated atherosclerosis, whereas mice infected with HSV-1 did not. These data indicate that a systemic immune response to any particular infectious agent is insufficient to induce enhanced atherosclerosis in the apoE-/- mouse and point to specific infections or immune mechanisms that might be essential for virally enhanced atherogenesis.

Objective: This study investigated whether magnetic resonance imaging (MRI) patterns were different between patients with Bell's palsy and those with herpetic facial palsy in whom varicella-zoster virus (VZV) or herpes simplex virus type 1 (HSV-1) reactivation had been confirmed by polymerase chain reaction (PCR) or serologic assay., Study Design: A retrospective study of 15 patients with acute peripheral facial palsy was performed to compare virologic tests and gadolinium (Gd)-enhanced MRI findings., Results: Ramsay Hunt syndrome was diagnosed in one patient. By use of virologic tests, zoster sine herpete (VZV reactivation without zoster) was diagnosed in four patients and HSV-1 reactivation in three. Bell's palsy was diagnosed in the remaining seven patients. No significant difference in the frequency of Gd-enhanced MRI was observed between herpetic facial palsy and Bell's palsy. However, in those patients who underwent MRI on the day viral reactivation was confirmed by PCR, Gd enhancement of the meatal fundus was observed infrequently. In addition, when MRI was performed within 10 days of the onset of palsy, Gd enhancement was not detected at the geniculate ganglion in any patients with herpetic facial palsy. By contrast, both the meatal fundus and the geniculate ganglion were enhanced in all patients with Bell's palsy, regardless of when MRI was performed with respect to the onset of palsy., Conclusion: This study shows a difference in the pattern of Gd enhancement at the meatal fundus and the geniculate ganglion between patients with Bell's palsy and those with herpetic facial palsy. The results suggest that the meatal fundus or the geniculate ganglion may be affected first by virus reactivation in patients with herpetic facial palsy.

Background: Considerable evidence suggests the role of an infectious agent in MS. The presence of Chlamydophila pneumoniae in CSF from patients with MS was shown earlier; to further examine this association the reactivity of the oligoclonal antibody response in the CSF of patients with MS to C pneumoniae antigens was determined and compared with other antigens., Methods: Seventeen patients with MS and 14 control subjects with other neurologic disease were studied. Affinity-driven immunoblot studies and solid-phase adsorption of CSF oligoclonal bands by elementary body antigens of C pneumoniae, viral antigens (measles and herpes simplex virus-1), bacterial antigen (Escherichia coli and Staphylococcus aureus), and heat shock protein-60 were performed., Results: Affinity-driven immunoblot studies demonstrated reactivity of oligoclonal bands in CSF samples from 16 patients with MS against elementary body antigens of C pneumoniae. None of the control subjects showed a prominent reactivity to elementary body antigens of C pneumoniae. In 14 of 17 patients with MS examined, oligoclonal bands were adsorbed either partially or completely from the CSF by elementary body antigens of C pneumoniae, but not by myelin basic protein, heat shock protein-60, or bacterial or viral antigens. In three patients with subacute sclerosing panencephalitis, adsorption of oligoclonal bands was seen with measles virus antigens but not with elementary body antigens of C pneumoniae., Conclusions: Oligoclonal bands in CSF of patients with MS include antibodies against Chlamydophila antigens.

We present three examples of patients with seborrheic keratoses complicated by necrotizing herpesvirus infection. Two patients had localized cutaneous herpetic infections, and the third patient had a generalized cutaneous herpesvirus infection. Two of the lesions were thought to be squamous cell carcinoma. The third was clinically identified as inflamed seborrheic keratosis. Herpesvirus infection was not clinically suspected in two of the patients. The histologic changes were similar in all cases. Epidermal proliferation was accompanied by hyperkeratosis and pseudo horn cyst formation. Extensive keratinocyte necrosis was present along with balloon degeneration of keratinocytes, herpetic viral inclusions, and multinucleated giant cells. Viral lesions of molluscum contagiosum and human papillomavirus have been observed in benign skin proliferations. Nevertheless, we were unable to find descriptions of herpesvirus involvement in seborrheic keratosis in a Medline search. Necrotic seborrheic keratoses should be carefully examined for the possibility of herpesvirus infection, a condition that may be improved by prompt medical intervention as demonstrated in one of our cases.

Purpose: To present a cluster of four patients with primary graft failure (PGF) who consecutively underwent a penetrating keratoplasty (PKP) during a period of 17 days in one institution. PKP was performed for reasons unrelated to herpes simplex infection. Herpes simplex virus type 1 (HSV-1) is presented as the possible cause of these PGFs., Methods: Viral culture of conjunctival swabs and of a bandage contact lens was performed on VERO, MRC-5, and Hep-2 cells. The four patients underwent subsequent regrafting. Polymerase chain reaction (PCR) for HSV-1 was carried out on aqueous humor and on a sample of iris and cornea with primers. Aqueous humor specimens were pretreated by boiling, and a qiagen extraction was performed according to the instructions of the manufacturer on biopsies of iris and cornea. Immunohistopathology was performed with polyclonal antibodies directed against HSV-1 and -2., Results: Culture of a conjunctival swab in three patients and culture of a bandage contact lens in the fourth patient were positive for HSV-1. In three of the four patients, PCR was positive for HSV-1 on aqueous humor and corneal graft tissue. PCR on iris tissue was positive in all patients. In three patients, culture for HSV-1 of aqueous humor and of iris tissue could not be carried out because of insufficient sample. Viral culture of the iris tissue in one patient and of the corneal graft in the four patients were negative. Immunohistopathologic examination was positive for HSV-1 in three cases., Conclusion: These case reports strongly support the hypothesis that HSV-1 can be the cause of PGF.

Purpose: Determinants of the natural history of recurrent herpes simplex virus (HSV) keratitis have not been consistently established. We assessed how previous HSV eye disease affects the risk of recurrent HSV keratitis and evaluated whether demographic and other variables play any predictive role., Methods: Three hundred forty-six patients in the placebo group of the Herpetic Eye Disease Study's Acyclovir Prevention Trial who had experienced an episode of HSV eye disease in the previous year were followed up for 18 months. Recurrences were categorized according to the type of involvement. Relative rates of recurrence were compared for categories of demographic variables, types and number of previous ocular HSV episodes, previous nonocular HSV infection, and month of the year., Results: Fifty-eight (18%) of the 346 patients developed epithelial keratitis and 59 (18%) developed stromal keratitis during the 18 months of follow-up. Previous epithelial keratitis did not significantly affect the risk of epithelial keratitis (p = 0.84). In contrast, previous stromal keratitis increased the risk of stromal keratitis 10-fold (p < 0.001), and the risk was strongly related to the number of previous episodes (p < 0.001). Age, gender, ethnicity, and nonocular herpes were not significantly associated with recurrences, and no seasonal effects were observed., Conclusion: Among patients who experienced active ocular HSV disease in the previous year, a history of epithelial keratitis was not a risk factor for recurrent epithelial keratitis. In contrast, previous, especially multiple, episodes of stromal keratitis markedly increased the probability of subsequent stromal keratitis.

Purpose: To evaluate the presence of herpes simplex virus (HSV) and human papilloma virus (HPV) in pterygia and phenotypically normal conjunctiva and the possible relation between viral presence and clinical information., Methods: Fifty pterygia and respective conjunctival specimens were obtained. A personal and family history was recorded for each patient. HSV and HPV detection and typing were accomplished by polymerase chain reaction amplification of viral sequences. Results were statistically analyzed., Results: HSV (type 1) was detected in 11 (22%), HPV (type 18) in 12 (24%), and both HSV-1 and HPV-18 in 3 (6%) of pterygia. No conjunctival specimen displayed HSV, whereas HPV was detected in four (8%). Postoperative recurrence and history of conjunctivitis were significantly more common in patients with simultaneous detection of HSV and HPV., Conclusion: The fact that HSV was not detected in conjunctival specimens implies a more specific correlation with pterygium, as compared with HPV. The detection of potentially oncogenic viruses, such as HSV and HPV, supports the concept that pterygium can be considered a neoplastic condition. The correlation of postoperative recurrence and a history of conjunctivitis with the simultaneous detection of HPV and HSV, implies a possible viral cooperation affecting the clinical profile of pterygium.

Purpose: To report the diagnosis, management, and outcome of acute retinal necrosis syndrome in children., Method: Case series of three consecutive children aged 11 years and younger who were diagnosed with acute retinal necrosis. In addition to full ocular and systemic examinations, the children underwent vitreous biopsy (Patients 1 and 2) or aqueous tap (Patient 3) for polymerase chain reaction analysis., Results: All patients had unilateral retinitis that was associated with preexisting chorioretinal scars, and two patients (Patients 1 and 3) had concurrent extraocular central nervous system abnormalities. Intraocular herpes simplex virus was detected in all three children: Type 1 in Patient 1 and Type 2 in Patients 2 and 3. In addition, all three children had a history of extraocular herpes simplex virus infection., Conclusions: Retinitis associated with preexisting chorioretinal scars and detectable intraocular herpes simplex virus on polymerase chain reaction was common to all three children with acute retinal necrosis.

The distribution of herpes simplex virus type 1 (HSV-1) in human geniculate, vestibular ganglia, and vestibular nuclei was determined in 10 human temporal bones and brainstems of five individuals by PCR. HSV-1 was found in 3 of 10 of each ganglia and vestibular nuclei. The various patterns of HSV-1 infection of vestibular structures are compatible with virus migration from the vestibular ganglia to the vestibular nuclei and from the ipsilateral to the contralateral vestibular nucleus via commissural fibers.

Purpose: To demonstrate the presence of an active herpetic dendrite in an eye-bank cornea., Case Report: One eye-bank cornea was studied. Viral cultures and polymerase chain reaction (PCR) testing were performed 4 days after tissue preservation. The presence or absence of herpes simplex virus (HSV) type 1 was investigated., Results: The presence of an active HSV dendrite in an eye-bank cornea was verified. HSV type 1 was confirmed using PCR amplification and restriction endonuclease DNA fragment analysis., Conclusion: This case suggests that HSV may remain viable in stored corneal tissue at 4 degrees C.

Purpose: To evaluate the clinical treatment efficacy of a long-lasting intravitreous injectable anti-cytomegalovirus (CMV) liposomal drug, 1-O-octadecyl-sn-glycerol-3-phosphonoformate (ODG-PFA)., Methods: Sixty-four pigmented rabbits were used for evaluation of the potency and duration of action of ODG-PFA after intravitreal injection using a herpes simplex virus (HSV)-1 retinitis model. For the potency evaluation, liposomal ODG-PFA was injected into rabbit vitreous at the same time that HSV-1 virus was inoculated onto the retina (simultaneous treatment). For the duration evaluation, ODG-PFA was injected days or weeks before inoculation (pretreatment). Retinitis was clinically graded by indirect ophthalmoscopy, and the retinitis scores were compared across the treatment and control groups., Results: Simultaneous treatment study revealed that ODG-PFA was much more potent than its parent compound, foscarnet (P = 0.0027). Pretreatment study indicated that ODG-PFA possesses a much longer antiviral effect (at least 2 weeks) than foscarnet after a single intravitreal injection., Conclusion: Liposomal ODG-PFA is a potent long-lasting intravitreal injectable antiviral compound that may be an ideal alternative for treatment of CMV retinitis in patients with acquired immunodeficiency syndrome.

Purpose: A new class of antiviral agent, cobalt chelates (the CTC series), was evaluated for treating epithelial herpetic keratitis, consequent stromal disease being the major infectious cause of blindness in industrial nations., Methods: Effects of CTC complexes were monitored in cell cultures and in a rabbit eye model, either infected with herpes simplex virus type 1 (HSV-1) or uninfected. Several antiviral concentrations of CTC complexes nontoxic to Vero cells were administered to rabbit eyes with HSV-1-induced keratitis. Corneal surface virus titers were measured, and corneal lesions of epithelial keratitis were monitored by slit-lamp microscopy and scored. Recovery rates and incidence were compared in eyes treated with CTC complexes, placebo, or clinically formulated trifluorothymidine (Viroptic), using nonparametric statistics., Results: All CTC complexes inhibited HSV-1 replication in vitro, CTC-96 being best. CTC-96, CTC-23, and CTC-67 eliminated (<1 plaque-forming unit[pfu]) corneal surface HSV-1 (otherwise >10(5) pfu) in order of descending potency, but CTC-82 was ineffective. CTC-96 (either 5 microg/ml six times daily or 10 microg/ml five times daily) accelerated herpetic dendritic keratitis recovery better than or the same as trifluorothymidine (10 mg/ml nine times daily). CTC complexes were nontoxic to Vero cells continuously exposed to < or =25 microg/ml; 50 microg/ml of CTC 96 nine times daily did not irritate uninfected rabbit eyes., Conclusion: Topical CTC-96 applications were at least as effective as Viroptic in diminishing disease signs and corneal surface virus at concentrations less than one-thousandth that of Viroptic.

Purpose: The goal of our study was to describe the herpes simplex virus type 1 (HSV 1) pneumonia patterns on CT scans and chest radiographs., Method: We retrospectively reviewed clinical records and chest radiographs of 24 patients with HSV 1 pneumonia and 10 with pneumonia from combined HSV and mixed flora infection. We also reviewed CT scans available for eight patients with HSV pneumonia and four with mixed pneumonia., Results: CT scans of eight patients with HSV pneumonia demonstrated multifocal segmental and subsegmental ground-glass opacities (n = 8), additional focal areas of consolidation (n = 6), scattered distribution (n = 6), and pleural effusions (n = 7). Chest radiographs (23 patients) showed patchy segmental and subsegmental ground-glass opacities and consolidation (n = 23), scattered distribution (n = 20), and pleural effusions (n = 12). Radiographic patterns for isolated HSV pneumonia and mixed flora pneumonia were not significantly different., Conclusion: With a growing population of at-risk immunosuppressed patients, it is important to recognize CT and chest radiography patterns consistent with, although nonspecific for, HSV 1 pneumonia.

Background: Chlamydia pneumoniae and the herpes viruses cytomegalovirus (CMV) and herpes simplex virus type 1 (HSV-1) have been associated with human atherosclerosis in seroepidemiological and separate histopathological studies. We investigated the concurrent presence of these microorganisms in patients undergoing carotid endarterectomy., Methods and Results: Endarterectomy specimens from 76 patients with carotid artery stenosis were stained for C. pneumoniae, CMV, and HSV-1 particles with specific IgG monoclonal antibodies by the avidin-biotin-peroxidase method. IgG antibodies to CMV and C. pneumoniae were also measured in the serum. These were correlated with plaque morphology and the presence of the microorganisms in the atherosclerotic plaques. C. pneumoniae was detected in 54 (71%) (95% confidence interval [CI], 59.5% to 80.9%), CMV was detected in 27 (35.5%) (CI, 24.9% to 47.3%), and HSV-1 was detected in 8 (10.5%) (CI, 4.7% to 19.7%) versus none of 20 (0%) control normal carotid artery and aortic tissue (autopsy) specimens (CI, 0% to 16.8%) (P<.001 for CMV and C. pneumoniae). At least one microorganism was detected in 59 of the specimens (77.6%) (CI, 66.6% to 86.4%), with a single microorganism present only in 35 (46%), two microorganisms present in 18 (23.7%) (CI, 14.7% to 34.8%), and all three present in 6 (7.9%) (CI, 3.0% to 16.4%). Atherosclerotic plaques with thrombosis were more likely to have C. pneumoniae (80.4%) or CMV (57.8%) than were plaques without thrombosis (56.7% and 16.7%, respectively; P=.04 and .007). There was no correlation between the presence of CMV and C. pneumoniae in the atherosclerotic vessels and serum antibody titers., Conclusions: C. pneumoniae and CMV are commonly detected in atherosclerotic plaques of the carotid arteries, but their presence cannot be predicted by measuring serum antibodies. The presence of these microorganisms may predispose to a greater risk of thrombosis in the plaques, but further studies are needed to confirm this observation.

The purpose of our study was to develop a method for detecting herpes simplex virus (HSV) DNA that combined the high sensitivity of the polymerase chain reaction (PCR) with the precise anatomical localization provided by in situ hybridization (ISH). We used in situ PCR (ISPCR), ISH, and standard PCR methods to determine the proportion of Vero cells carrying HSV-1-specific DNA before and after 1, 2, and 4 h of infection with HSV-1 or with HSV-2. Uninfected Vero cells and Vero cells infected with HSV-2 were never found to be positive for HSV-1 DNA by either ISPCR, ISH, or PCR. In contrast, using ISPCR, HSV-1 infected Vero cells showed an increase in the percentage of cells containing HSV-1 DNA from 20% at 1 h to 76% at 4 h after infection. Comparing the ISPCR results with ISH and standard PCR demonstrated that ISPCR was markedly more sensitive than ISH; in fact, the sensitivity of in situ PCR was similar to that seen with standard PCR. These results demonstrate that ISPCR is a highly sensitive method for amplifying genomic DNA sequences within intact single cells. This technique combines the exquisite sensitivity of conventional PCR technology with the precise cellular localization afforded by ISH. In addition, it allows for an accurate quantitative determination of the number of virally infected cells.