Varicella-zoster Virus Vaccine Strain Research Articles

Disseminated vaccine-strain varicella-zoster virus reactivation in an adolescent with secondary immunodeficiency: a case report and literature review

BackgroundRoutine childhood immunization against varicella-zoster virus has led to a dramatic reduction in the incidence of primary varicella. However, there are rare, yet significant cases reported of reactivated Oka-strain varicella, primarily in immunocompromised hosts.Case presentationA 16-year-old female with Hodgkin’s lymphoma developed a vesicular rash shortly after completing all chemotherapy treatment. Swabs obtained from the vesicles were positive for varicella-zoster virus. By the time of hospitalization, the patient developed a disseminated rash involving multiple dermatomes. Subsequent polymerase chain reaction confirmed Oka vaccine-strain varicella-zoster virus. The patient had previously received a primary series of immunizations against varicella in 2008 and 2012, with her 2nd dose given 11 years prior to her development of vaccine-strain herpes zoster and 10 years prior to her diagnosis of Hodgkin’s lymphoma, respectively. The patient was treated with parenteral acyclovir upon hospitalization and monitored clinically for cutaneous disease progression as well as sequelae. After 8 days of inpatient treatment, her rash had stopped spreading with no new lesions. All earlier lesions had crusted over. No serious sequelae of disease such as pneumonitis, hepatitis, encephalitis, or meningitis occurred, and she made a complete recovery.ConclusionsThere are individual and community-wide benefits to childhood immunization against varicella. This case highlights an unusual presentation of disseminated vaccine-strain herpes zoster in an adolescent with secondary immunodeficiency 11 years after completing primary immunization. In addition, this case informs pediatricians of complications that can arise in immunized subjects if they become immunosuppressed years later. The only way to distinguish between wild-type and vaccine-strain herpes zoster was by viral genotyping. Providers should be cognizant of potential vaccine virus reactivation in their differential. Considerations for work-up and management should include infection control and viral resistance in refractory cases.

Nanopore sequencing in distinguishing between wild-type and vaccine strains of Varicella-Zoster virus

BackgroundThe introduction of varicella vaccines into routine pediatric immunization programs has led to a considerable reduction in varicella incidence. However, there have been reports of varicella, herpes zoster, and meningitis caused by the vaccine strain of varicella-zoster virus (VZV), raising concerns. Establishing the relationship between the wild-type and vaccine strains in VZV infections among previously vaccinated individuals is crucial. Differences in the single nucleotide polymorphisms (SNPs) among vaccine strains can be utilized to identify the strain. In this study, we employed nanopore sequencing to identify VZV strains and analyzed clinical samples. MethodsWe retrospectively examined vesicle and cerebrospinal fluid samples from patients with VZV infections. One sample each of the wild-type and vaccine strains, previously identified using allelic discrimination real-time PCR and direct sequencing, served as controls. Ten samples with undetermined VZV strains were included. After DNA extraction, a long PCR targeting the VZV ORF62 region was executed. Nanopore sequencing identified SNPs, allowing discrimination between the vaccine and wild-type strains. ResultsNanopore sequencing confirmed SNPs at previously reported sites (105,705, 106,262, 107,136, and 107,252), aiding in distinguishing between wild-type and vaccine strains. Among the ten unknown samples, nine were characterized as wild strains and one as a vaccine strain. Even in samples with low VZV DNA levels, nanopore sequencing was effective in strain identification. ConclusionThis study validates that nanopore sequencing is a reliable method for differentiating between the wild-type and vaccine strains of VZV. Its ability to produce long-read sequences is remarkable, allowing simultaneous confirmation of known SNPs and the detection of new mutations. Nanopore sequencing can serve as a valuable tool for the swift and precise identification of wild-type and vaccine strains and has potential applications in future VZV surveillance.

Progressive shingles in a toddler due to reactivation of Varicella Zoster vaccine virus four days after infection with SARS-CoV-2; a case report

BackgroundHerpes zoster (HZ) is the clinical syndrome associated with reactivation of latent varicella-zoster virus (VZV). Several factors have been implicated to promote VZV reactivation; these include immunosuppression, older age, mechanical trauma, physiologic stress, lymphopenia, and more recently, infection with severe acute respiratory syndrome coronavirus-2 (SARS- CoV-2). Recent reports suggest an increase in the number of HZ cases in the general population during the global COVID-19 pandemic. However, it is unknown what proportion of HZ during the pandemic is due to reactivation of wild-type or vaccine-strain VZV.CaseHere we report the first known case of HZ concomitant with SARS-CoV2 infection in a 20-month-old female who was treated with a single dose of dexamethasone, due to reactivation of the vaccine-type strain of VZV after presenting with a worsening vesicular rash.ConclusionIn this case, we were able to show vaccine-strain VZV reactivation in the context of a mild acute symptomatic COVID-19 infection in a toddler. Being able to recognize HZ quickly and effectively in a pediatric patient can help stave off the significant morbidity and mortality associated with disease process.

A booster administration of the OKA/SK strain causes fatal disseminated varicellain an immunocompetent child.

Live varicella vaccines are known to provide robust immunity against varicella zoster virus (VZV) infections. However, problems with viral attenuation have led to pathogenic VZV vaccine strains causing varicella-like rash and herpes zoster in immunocompetent children after immunization. We report the first fatal case of VZV infection caused by OKA/SK strain contained in the vaccine administrated as a booster shot in an immunocompetent child,which has been independently developed from any currently available varicella vaccines that are OKA strain or MAV/06 strain based. The patient died due to sudden pulmonary alveolar hemorrhage as a secondary complication of VZV pneumonitis. Sequencing of the four SNPs unique to the OKA/SK strain (SNP loci 14 035T; 32 626C; 58 777G; 70 319G) enabled discrimination of the strain responsible for the disseminated infection. OKA/SK strain does not have any SNPs in ORF62 postulated to be responsible for the attenuation of varicella vaccines which have been safely and effectively used world-wide or locally, and exclusively enriches a virulent factor in ORF31 identified in parental OKA strain, thus possibly resulting in disseminated VZV infection leading to mortality. Therefore, actions need to be taken to prevent vaccine related morbidity and mortality in children.

Safety and immunogenicity of a skin- and neuro-attenuated live vaccine for varicella: a randomized, double-blind, controlled, dose-escalation and age de-escalation phase 1 clinical trial

Despite the success in decreasing varicella-related disease burden, live-attenuated Oka vaccine strain of varicella-zoster virus (vOka) remains neuro-virulence and may establish latency and reactivate, raising safety concerns. Here we aimed to evaluate the safety and immunogenicity of a skin- and neuro-attenuated varicella vaccine candidate (v7D). This is a randomized, double-blind, placebo-controlled, dose-escalation and age de-escalation phase 1 clinical trial conducted in Liuzhou, China (ChiCTR1900022284). Eligible healthy participants aged 1-49 years, with no history of varicella vaccination and had no history of varicella or herpes zoster were sequentially enrolled and allocated to subcutaneously receive one of the three doses (3.3, 3.9, and 4.2 lg PFU) of v7D, vOka or placebo in a dose-escalation and age de-escalation manner. The primary outcome was safety, assessed by adverse events/reactions within 42 days after vaccination and serious adverse events (SAEs) throughout six months after vaccination. The secondary outcome was immunogenicity, assessed by the VZV IgG antibodies measured with fluorescent antibody to membrane antigen (FAMA) assay. Between April 2019 and March 2020, totally 224 participants were enrolled. Within 42 days post-vaccination, the incidences of adverse reactions were 37.5%-38.7% in the three doses of v7D groups which were similar to that of the vOka (37.5%) and placebo (34.4%) groups. No SAE has been judged as causally related to vaccination. At 42 days post-vaccination, 100% of children aged 1-12 years in the per-protocol set of immunogenicity cohort of the v7D groups became seropositive. Meanwhile, in the intent-to-treat set of immunogenicity cohort of subjects aged 1-49 years, the geometric mean increases of the three groups of v7D vaccine were 3.8, 5.8 and 3.2, respectively, which were similar to that of the vOka vaccine group (4.4) and significantly higher than that of the placebo group (1.3). The candidate v7D vaccine has been preliminarily shown to be well-tolerated and immunogenic in humans. The data warrant further evaluation of the safety advantage and efficacy of v7D as a varicella vaccine. The National Natural Science Foundation of China, CAMS Innovation Fund for Medical Sciences, and Beijing Wantai CO., LTD.

Disseminated varicella zoster virus infection following live attenuated herpes zoster vaccine: descriptive analysis of reports to Australia’s spontaneous vaccine pharmacovigilance system, 2016–2020

ObjectivesTo examine the reported incidence and features of disseminated varicella zoster virus (VZV) infection following live attenuated herpes zoster vaccine live (ZVL: Zostavax, Merck) in immunocompromised people in Australia.Design and...

Genetic analysis of varicella-zoster virus in patients with viral anterior uveitis

Objective: To analyze the intraocular varicella-zoster virus (VZV) infection and genetic characteristics in patients clinically diagnosed with viral anterior uveitis. Methods: A total of 83 aqueous humor samples were collected from patients clinically diagnosed with viral anterior uveitis infection in China from June 2018 to July 2019. The positive samples infected with VZV were screened by real time polymerase chain reaction, and the single nucleotide polymorphisms on the open reading frames 22, 38 and 62 of the positive samples were amplified and analyzed. According to the gene characteristics of the amplified target fragment, the vaccine strain and wild strain (8 vaccine strains and the rest were wild strains) were identified to determine the genotype. Results: There were 83 patients (31 females and 52 males) with viral uveitis infection, whose mean age was 51.0 (45.5, 61.0) (range: 15-83) years,, and, of which 57.8% (48 cases) were infected with viral uveitis over 50 years of age. None of the patients had a history of varicella or herpes zoster vaccination. Of the samples of 83 patients infected with viral uveitis, 57 (68.6%) were positive for VZV. Among them, 14 were successfully amplified to obtain the target fragment gene sequences, all of which were wild strains by analysis, and belonged to Clade2 of genotype, which was the same as the VZV vaccine strain types infected by varicella and herpes zoster patients in China. Conclusion: From 2018 to 2019, VZV infection in Chinese patients with viral anterior uveitis was a wild strain, and the genotype belonged to Clade2 as the vaccine strain, which was the same as the main epidemic genotype of VZV infection in Chinese patients with varicella and herpes zoster.

Herpes Zoster in a 23-month-old Girl: A Case Report

<p>帶狀疱疹是潛伏在人體的水痘帶狀疱疹病毒再活化所造成。兒童帶狀疱疹狀並不常見，未滿兩歲更是罕見。本個案為1歲11個月大的女孩，過去未長過水痘，滿一歲時曾打過活性減毒的水痘疫苗。接種後第348天，在施打疫苗的左大腿（第三及第四腰椎的神經皮節）長出帶狀疱疹。經Acyclovir治療後，恢復迅速。依此個案的病史和臨床特徵推測，其帶狀疱疹可能是水痘疫苗所造成。若想確認帶狀疱疹在曾打過水痘疫苗的病人身上，到底是野生株或疫苗株的病毒所造成，最好的方法是做PCR檢驗。根據研究，水痘疫苗的確可能造成帶狀疱疹，但有施打疫苗者，其發生率和症狀均低於未施打疫苗者。整體而言，施打水痘疫苗，不僅能預防水痘，亦能預防帶狀疱疹，施打兩劑保護力更好。</p> <p> </p><p>Herpes zoster, caused by reactivation of the varicella-zoster virus (VZV), is not commonly seen in children, especially in those under 2 years of age. We reported a case of a 23-month-old girl with herpes zoster. She had no personal history of chicken pox. She was immunized with the live attenuated varicella vaccine at 12 months of age. Nevertheless, she developed herpes zoster in the left thigh (L3-L4 dermatomes) around the immunization site 348 days after the varicella vaccination. Her clinical symptoms improved rapidly after acyclovir treatment. Based on the personal history and clinical presentation, it is possible that her herpes zoster was caused by the virus of varicella vaccine. The best way to identify wild-type or vaccine-strain VZV in a herpes zoster patient with a prior history of varicella vaccination is by viral genome detection using polymerase chain reaction (PCR). As previous studies indicate, vaccine-strain herpes zoster can occur after varicella vaccine. However, the incidence and symptoms of herpes zoster occur less often in vaccinated individuals than in unvaccinated ones. In general, varicella vaccine can prevent not only varicella but also herpes zoster. The preventive effect of two-dose varicella vaccination is better than that of one-dose vaccination.</p> <p> </p>

Deep Immune Profiling of Patients with STAT1 Gain-of-Function: Revealing New Mechanisms of Pathology

Background: Patients with heterozygous signal transducer and activator of transcription 1 (STAT1) gain-of-function (GOF) pathogenic variants exhibit an array of clinical phenotypes including susceptibility to multiple infections, autoimmunity, and cancer predisposition. Previous studies to characterize the pathways involved and explore therapeutic interventions have been constrained by the technology to perform in-depth immunophenotyping. Mass cytometry has allowed us to perform extensive immune profiling of patients with inborn errors of immunity (IEI) to help gain a better understanding of disease pathology. STAT1 gain-of-function (GOF) mutations have demonstrated higher levels of phosphorylated STAT1 in response to type I and II interferons, but the response to other cytokines is less understood. Using advanced cytometry, we demonstrate a unique pattern of STAT1 phosphorylation in response to IL-6 stimulation in T-cell subsets and this differential pattern may play a role in T-cell differentiation and memory in STAT1 GOF patients.Cases: We report two patients with heterozygous STAT1 GOF mutations in the coiled-coil domain. For both patients, the clinical phenotype was largely consistent with other STAT1 GOF patients, one (P1, c.800C>T; p.ala267Val) presented with secondary HLH due to histoplasmosis, and the second (P2, c.866A>G; p.Tyr289Cys) presented with presumed vaccine strain varicella zoster virus (VZV) meningitis and subsequent history of recurrent herpes simplex virus (HSV) skin lesions. Patient peripheral blood mononuclear cells (PBMCs) were evaluated by fluorescence flow cytometry and cytometry by time of flight (CyTOF) as previously described (Roussel et al. J Leukoc Biol. 2017) to evaluate the impact of STAT1 GOF mutations on T-cell immunophenotype and cytokine signaling.Results: Utilizing cytometric data, we were able to identify similar patterns of T cell distribution on t-distributed stochastic neighbor embedding (t-SNE) plots for both patients with STAT1 GOF that were distinct compared to healthy controls (Fig 1a). In the T-cell compartment, both patients had decreased Th17 and Treg populations and an increased Th1/Th2 ratio compared to healthy donor (Fig 1b). In response to stimulation with IFNg or IL-6, there were also clear patterns with the two patients compared to healthy controls. Levels of p-STAT1 and p-STAT3 were assessed in STAT1 GOF and health donor PBMCs at several times points between 15 and 120 minutes, after stimulation with either IFNg or IL-6. Using fluorescence flow, we found that IL-6 stimulation led to greater than anticipated p-STAT1 response at all timepoints compared to a much more muted response to IFNg. The cell subsets highlighted in the t-SNE after IL-6 stimulation differ from the cell subsets that respond to IFNg stimulation in patients and healthy control (Fig 2a), suggesting that distinct cell populations are driving the response to IL-6. By evaluating these IL-6 responsive subsets in comparison with healthy control by CyTOF, we identified an exaggerated p-STAT1 response to IL-6 in the memory T-cell populations in P2 (Fig 2b).Conclusions: These two unique clinical presentations demonstrate that with similar mutations in the coiled-coil domain of STAT1, yet largely differing clinical presentations, the immune profiling patterns of the patients compared to healthy controls can drive further work on disease characterization and therapeutic interventions. This is relevant for this patient cohort, as treatment recommendations for STAT1 GOF are not well established. Long-term outcomes with JAK inhibition are lacking and transplant survival rates to date have been very poor compared to other immune diseases including familial HLH. With identification of IL-6 signaling playing a potential role in T-cell maturation, further studies will need to be performed to determine if IL-6 modulation could be used as a treatment modality. We conclude that performing deep immunophenotyping of patients with inborn errors of immunity (IEIs) such as STAT1 GOF can point to new disease mechanisms of human immunity and inflammation and lead to improved understanding of the role of cytokine and cellular signaling in normal hematopoiesis and cellular maturation. [Display omitted] DisclosuresRathmell: Sitryx: Consultancy, Current equity holder in publicly-traded company, Research Funding; Caribou: Consultancy, Current equity holder in publicly-traded company, Current holder of stock options in a privately-held company; Nirogy: Consultancy, Current holder of stock options in a privately-held company; Merck: Speakers Bureau; Pfizer: Speakers Bureau; Mitobridge: Consultancy; Incyte: Research Funding; Calithera: Research Funding; Tempest: Research Funding.

Genetic changes in plaque-purified varicella vaccine strain Suduvax during in vitro propagation in cell culture.

Infection by varicella-zoster virus (VZV) can be prevented by using live attenuated vaccines. VZV vaccine strains are known to evolve rapidly in vivo, however, their genetic and biological effects are not known. In this study, the plaque-purified vaccine strain Suduvax (PPS) was used to understand the genetic changes that occur during the process of propagation in in vitro cell culture. Full genome sequences of three different passages (p4, p30, and p60) of PPS were determined and compared for genetic changes. Mutations were found at 59 positions. The number of genetically polymorphic sites (GPS) and the average of minor allele frequency (MAF) at GPSs were not significantly altered after passaging in cell culture up to p60. The number of variant nucleotide positions (VNPs), wherein GPS was found in at least one passage of PPS, was 149. Overall, MAF changed by less than 5% at 52 VNPs, increased by more than 5% at 42 VNPs, and decreased by more than 5% at 55 VNPs in p60, compared with that seen in p4. More complicated patterns of changes in MAF were observed when genetic polymorphism at 149 VNPs was analyzed among the three passages. However, MAF decreased and mixed genotypes became unequivocally fixed to vaccine type in 23 vaccine-specific positions in higher passages of PPS. Plaque-purified Suduvax appeared to adapt to better replication during in vitro cell culture. Further studies with other vaccine strains and in vivo studies will help to understand the evolution of the VZV vaccine.

Preventing Transmission of Vaccine-Associated Viral Infections from a Patient With Severe Combined Immune Deficiency

Background: The transmissibility of vaccine-strain viruses from immunocompromised patients, such as those with severe combined immune deficiency (SCID) is unknown. The infection control management of a patient diagnosed with SCID and infected with vaccine-strain varicella zoster virus (VZV) and measles virus is described below. A previously healthy, full-term boy was vaccinated at 14 months with measles mumps rubella varicella (MMR) vaccine. He had received prior vaccinations, including rotavirus, without adverse effects. During the 6 weeks after vaccination, the patient developed signs and symptoms clinically consistent with chicken pox and measles. An immune work-up revealed SCID. Methods: The Alberta Health Services (AHS) SCID protocol was followed to manage the patient upon admission at 17 months of age. Multiple meetings with various stakeholders were held to ensure appropriate precautions were followed to minimize the risk of pathogen transmission. Results: The patient was placed on airborne and contact precautions in a negative-pressure room. The pressure differential of the room to the corridor was continually monitored and displayed at the entry to the room. Staff known to be immune to VZV or measles were not required to wear an N95 respirator. All intrahospital movement of the patient was coordinated with the respective care teams and departments, including infection prevention and control, facilities maintenance and engineering, respiratory therapy, and diagnostic imaging. A mask was placed on the patient when movement outside the room was required. VZV testing was positive for the Oka/vaccine strain on all samples tested (ie, nasopharyngeal, skin, blood, and cerebrospinal fluid). Nasopharyngeal swabs and blood were PCR positive for measles genotype A/vaccine strain virus. Both viruses were persistently positive in spite of treatment with acyclovir, valganciclovir, varicella zoster immune globulin, and intravenous immune globulin. Conclusions: There is currently no documented transmission of measles vaccine-strain virus, and transmission of VZV vaccine-strain virus is rare. According to the AHS SCID protocol, the use of airborne and contact precautions for a patient identified with measles and/or VZV supersedes the use of a positive-pressure room for patients identified with SCID. Newborn screening for SCID was implemented in Alberta in June 2019. As a result, more SCID patients will be diagnosed earlier in their course, and therefore prior to most routine vaccinations. However, newborn screening will not pick up some types of combined immune deficiencies. Some children may still be at risk of vaccine-associated illnesses due to undiagnosed underlying immune deficiencies.Funding: NoneDisclosures: None

Characterization of binding of Varicella zoster virus vaccine strains to preparations of mouse brain membrane receptors

Purpose: characterization of vFiraVax (the causative agent of chickenpox - VZV) and vZelVax (the causative agent of shingles - HZ) vaccine strains by their ability to bind to preparations of brain membrane receptors of SPF BALB/c mice.Materials and Methods. The study was performed on cold-adapted vFiraVax VZV and vZelVax HZ vaccine strains developed by the authors on the basis of the wild-type parental pFira VZV virus (chickenpox causative agent) and the latent parental lpZel HZ virus (shingles causative agent); vOka vaccine strains isolated from vaccines against VZV infection from two manufactures (United Kingdom and USA); the HEL-3 strain of diploid cells from human embryonic lung tissue, the MC 27 strain of diploid cells from human embryonic musculocutaneous tissue, primary and diploid cells from guinea pig fetal fibroblasts. The VZV infectivity was estimated by the limiting dilution method using MC 27 cell cultures or guinea pig fetal fibroblasts. The virus titer was measured by the hemadsorption test performed with suspensions of red blood cells from guinea pig or human type 0 positive blood. Negative staining and electron microscopy were used to study the virus preparation. The immunogenicity of vFiraVax VZV and vZelVax HZ virus strains was compared with the immunogenicity of vOka VZV virus strains from different manufacturers by using a cross-neutralization test with immune sera.Results. The Russian cold-adapted vFiraVax VZV and vZelVax HZ vaccine strains, the latent parental lpZel HZ virus and the vOka VZV vaccine strain (United Kingdom) did not bind to preparations of brain neuroreceptors of SPF BALB/c mice as distinct from the wild-type parental pFira VZV variant and vOka VZV vaccine strains (USA); the absent neurotropism of Russian vFiraVax VZV and vZelVax HZ vaccine strains is not connected with the decreased immunogenicity in relation to foreign counterparts; the electron microscope study of the vFiraVax VZV virus containing liquid concentrate detected VZV nucleocapsids.Conclusion. The differences in the VZV ability to bind to preparations of brain membrane receptors of SPF BALB/c mice can be explained by the differences in the technology of vaccine manufacturing, including attenuation techniques, obtaining of the vaccine strain, specific characteristics of the latent parental lpZel HZ virus. The absence of the binding with brain neuroreceptors of SPF mice has been proved for the Russian vFiraVax VZV and vZelVax HZ vaccine strains which was is not connected with a decrease in their immunogenicity. The method of assessment of the binding ability of VZV vaccine strains can be used as a preliminary characteristic of neurotropism for newly created vaccine strains and for vaccine products.

Frequency of subclinical herpes zoster in pediatric hematology-oncology patients receiving chemotherapy: A retrospective cohort analysis.

Varicella-zoster virus (VZV) reactivation from the enteric nervous system can cause ileus (Ogilvie's syndrome) in adult patients. Since no pediatric cases have been described, we sought to retrospectively analyze VZV reactivation in pediatric hematology-oncology patients to determine whether VZV infection including subclinical VZV reactivation can induce gastrointestinal complications such as Ogilvie's syndrome. Thirty-five patients who received chemotherapy at our institution between September 2013 and June 2018 were included. Serum samples were collected weekly during hospitalization and every 3 months during outpatient maintenance chemotherapy. A real-time polymerase chain reaction assay was used to measure VZV DNA load in serum. The clinical features of patients with VZV infection were retrospectively analyzed. Of 1165 serum samples, 7 (0.6%) were positive for VZV DNA. VZV DNA was detected in 3 of 35 patients. In patient A, VZV DNA was detected during two episodes. The first episode involved varicella-like eruptions caused by the Oka VZV vaccine strain. The second episode involved herpes zoster (HZ) caused by the same strain. Patients B and C had a clinical course that was typical for HZ caused by wild-type VZV. No gastrointestinal symptoms were observed at the time of VZV infection in these three patients. VZV DNA was not detected in any other samples. No pediatric cases with Ogilvie's syndrome caused by VZV reactivation were demonstrated in this cohort. Additionally, no subclinical VZV reactivation was found in this cohort. Further study is needed to elucidate the precise incidence of pediatric Ogilvie's syndrome caused by VZV reactivation.

2767. Variation in Incidence of Pediatric Herpes Zoster by First- and Second-Dose Varicella Vaccine Formulations

BackgroundVaricella (VAR) and measles-mumps-rubella (MMR) vaccines are recommended for children at ages 12–15 months and 4–6 years. These are administered as separate MMR and VAR vaccines (MMR+VAR) or as combined measles-mumps-rubella-varicella (MMRV) vaccine. Herpes zoster (HZ), caused by wild-type or vaccine-strain varicella-zoster virus, can occur in children after varicella vaccination. It is unknown whether HZ incidence after varicella vaccination varies by vaccine formulation or simultaneous receipt of MMR.MethodsUsing data from six integrated health systems, we examined HZ incidence among children who turned 12 months old during 2003–2008 and received varicella and MMR vaccines according to routine recommendations. All HZ cases ≥ 21 days after first varicella vaccination were identified using ICD-9 codes from inpatient, outpatient, emergency room encounters, and claims data, through 2014. HZ incidence was examined by vaccine formulation (MMR+VAR, MMRV, or VAR without same-day MMR) and doses received and compared using incidence rate ratios (IRR).ResultsAmong 199,797 children, we identified 601 HZ cases. Crude HZ incidence after first-dose MMR+VAR (18.6 [95% CI 11.1–29.2] cases/100,000 person-years) was similar to the rate after first-dose MMRV (17.9 [95% CI 10.6–28.3] cases/100,000 person-years), but approximately double the rate among those with first-dose VAR without same-day MMR (7.5 [95% CI 3.1–15.0] cases/100,000 person-years); see Table 1. The IRR for HZ after first-dose MMR+VAR or MMRV, compared with VAR, was 2.5 (95% CI 1.4–4.4; P = 0.002). When examining any first or second dose formulation, crude HZ incidence was lower after the second varicella vaccine dose (13.9 cases/100,000 person-years), than in the period before the second dose (i.e., between first and second doses or after the first dose in children with only one dose; 21.8 cases/100,000 person-years, P < 0.0001). HZ incidence was also lower after two varicella vaccine doses in each of the three first-dose formulation groups.ConclusionHZ incidence among children varied by first-dose varicella vaccine formulation and number of varicella vaccine doses. Regardless of the first-dose varicella vaccine formulation, children who received two vaccine doses had lower HZ incidence after the second dose. Disclosures All authors: No reported disclosures.

Transmission of Vaccine-Strain Varicella-Zoster Virus: A Systematic Review.

Live vaccines usually provide robust immunity but can transmit the vaccine virus. To assess the characteristics of secondary transmission of the vaccine-strain varicella-zoster virus (Oka strain; vOka) on the basis of the published experience with use of live varicella and zoster vaccines. Systematic review of Medline, Embase, the Cochrane Library, Cumulative Index to Nursing and Allied Health Literature, and Scopus databases for articles published through 2018. Articles that reported original data on vOka transmission from persons who received vaccines containing the live attenuated varicella-zoster virus. We abstracted data to describe vOka transmission by index patient's immune status, type (varicella or herpes zoster) and severity of illness, and whether transmission was laboratory confirmed. Twenty articles were included. We identified 13 patients with vOka varicella after transmission from 11 immunocompetent varicella vaccine recipients. In all instances, the vaccine recipient had a rash: 6 varicella-like and 5 herpes zoster. Transmission occurred mostly to household contacts. One additional case was not considered direct transmission from a vaccine recipient, but the mechanism was uncertain. Transmission from vaccinated immunocompromised children also occurred only if the vaccine recipient developed a rash postvaccination. Secondary cases of varicella caused by vOka were mild. It is likely that other vOka transmission cases remain unpublished. Healthy, vaccinated persons have minimal risk for transmitting vOka to contacts and only if a rash is present. Our findings support the existing recommendations for routine varicella vaccination and the guidance that persons with vaccine-related rash avoid contact with susceptible persons at high risk for severe varicella complications.

Current In Vitro Models to Study Varicella Zoster Virus Latency and Reactivation.

Varicella zoster virus (VZV) is a highly prevalent human pathogen that causes varicella (chicken pox) during primary infection and establishes latency in peripheral neurons. Symptomatic reactivation often presents as zoster (shingles), but it has also been linked to life-threatening diseases such as encephalitis, vasculopathy and meningitis. Zoster may be followed by postherpetic neuralgia, neuropathic pain lasting after resolution of the rash. The mechanisms of varicella zoster virus (VZV) latency and reactivation are not well characterized. This is in part due to the human-specific nature of VZV that precludes the use of most animal and animal-derived neuronal models. Recently, in vitro models of VZV latency and reactivation using human neurons derived from stem cells have been established facilitating an understanding of the mechanisms leading to VZV latency and reactivation. From the models, c-Jun N-terminal kinase (JNK), phosphoinositide 3-kinase (PI3K) and nerve growth factor (NGF) have all been implicated as potential modulators of VZV latency/reactivation. Additionally, it was shown that the vaccine-strain of VZV is impaired for reactivation. These models may also aid in the generation of prophylactic and therapeutic strategies to treat VZV-associated pathologies. This review summarizes and analyzes the current human neuronal models used to study VZV latency and reactivation, and provides some strategies for their improvement.

Adverse events after vaccination among HIV-positive persons, 1990-2016.

Human immunodeficiency virus (HIV) causes immune dysregulation, potentially affecting response to vaccines in infected persons. We investigated if unexpected adverse events (AEs) or unusual patterns of AEs after vaccination were reported among HIV-positive persons. We searched for domestic reports among HIV-positive persons to the Vaccine Adverse Event Reporting System (VAERS) during 1990–2016. We analyzed reports by age group (<19 and ≥19 years), sex, serious or non-serious status, live vaccine type (live versus inactivated), AEs reported, and CD4 counts. Of 532,235 reports received, 353 (0.07%) described HIV-positive persons, of whom 67% were aged ≥19 years, and 57% were male; most reports (75%) were non-serious. The most commonly reported inactivated vaccines were pneumococcal polysaccharide (27%) and inactivated influenza (27%); the mostly reported common live virus vaccines were combination measles, mumps, and rubella (8%) and varicella (6%). Injection site reactions were commonly reported (39%). Of 67 reports with CD4 counts available, 41 (61%) described persons immunocompromised at time of vaccination (CD4 count <500 cells/mm3), and differed from overall reports only in that varicella was the most common live virus vaccine (4 reports). Of 22 reports describing failure to protect against infection, 6 described persons immunocompromised at time of vaccination, among whom varicella vaccine was most common (3 reports). Of 66 reports describing live virus vaccines, 7 described persons with disseminated infection: 6 had disseminated varicella, 3 of whom had vaccine strain varicella-zoster virus. Of 18 reported deaths, 7 resulted from disseminated infection: 6 were among immunocompromised persons, 1 of whom had vaccine strain varicella-zoster virus. We identified no unexpected or unusual patterns of AEs among HIV-positive persons. These data reinforce current vaccine recommendations for this risk group. However, healthcare providers should know their HIV-positive patients’ immune status because immunocompromising conditions can potentially increase the risk of rare, but severe, AEs following vaccination with live virus vaccines.

Analysis of IE62 mutations found in Varicella-Zoster virus vaccine strains for transactivation activity.

Live attenuated vaccine strains have been developed for Varicella-Zoster virus (VZV). Compared to clinically isolated strains, the vaccine strains contain several non-synonymous mutations in open reading frames (ORFs) 0, 6, 31, 39, 55, 62, and 64. In particular, ORF62, encoding an immediate-early (IE) 62 protein that acts as a transactivator for viral gene expression, contains six non-synonymous mutations, but whether these mutations affect transactivation activity of IE62 is not understood. In this study, we investigated the role of non-synonymous vaccine-type mutations (M99T, S628G, R958G, V1197A, I1260V, and L1275S) of IE62 in Suduvax, a vaccine strain isolated in Korea, for transactivation activity. In reporter assays, Suduvax IE62 showed 2- to 4-fold lower transactivation activity toward ORF4, ORF28, ORF29, and ORF68 promoters than wild-type IE62. Introduction of individual M99T, S628G, R958G, or V1197A/I1260V/L1275S mutations into wild-type IE62 did not affect transactivation activity. However, the combination of M99T within the N-terminal Sp transcription factor binding region and V1197A/I1260V/L1275S within the C-terminal serine-enriched acidic domain (SEAD) significantly reduced the transactivation activity of IE62. The M99T/V1197A/I1260V/L1275S mutant IE62 did not show considerable alterations in intracellular distribution and Sp3 binding compared to wild-type IE62, suggesting that other alteration(s) may be responsible for the reduced transactivation activity. Collectively, our results suggest that acquisition of mutations in both Met 99 and the SEAD of IE62 is responsible for the reduced transactivation activity found in IE62 of the VZV vaccine strains and contributes to attenuation of the virus.

Post-licensure safety surveillance of zoster vaccine live (Zostavax®) in the United States, Vaccine Adverse Event Reporting System (VAERS), 2006–2015

ABSTRACTBackground: Herpes zoster (HZ), or shingles, is caused by reactivation of varicella-zoster virus in latently infected individuals. Live-attenuated HZ vaccine (zoster vaccine live, ZVL) is approved in the United States for persons aged ≥50 years and recommended by the CDC for persons ≥60 years. Methods: We analyzed U.S. reports of adverse events (AEs) following ZVL submitted to the Vaccine Adverse Event Reporting System (VAERS), a spontaneous reporting system to monitor vaccine safety, for persons vaccinated May 1, 2006, through January 31, 2015. We conducted descriptive analysis, clinical reviews of reports with selected pre-specified conditions, and empirical Bayesian data mining. Results: VAERS received 23,092 reports following ZVL, of which 22,120 (96%) were classified as non-serious. Of reports where age was documented (n = 18,817), 83% were in persons aged ≥60 years. Reporting rates of AEs were 106 and 4.4 per 100,000 ZVL doses distributed for all reports and serious reports, respectively. When ZVL was administered alone among persons aged ≥50 years, injection site erythema (27%), HZ (17%), injection site swelling (17%), and rash (14%) were the most commonly reported symptoms among non-serious reports; HZ (29%), pain (18%), and rash (16%) were the most commonly reported symptoms among serious reports. Six reports included laboratory evidence of vaccine-strain varicella-zoster virus (Oka/Merck strain) infection; AEs included HZ, HZ- or varicella-like illness, and local reaction with vesicles. In our review of reports of death with sufficient information to determine cause (n = 46, median age 75 years), the most common causes were heart disease (n = 28), sepsis (n = 4), and stroke (n = 3). Empirical Bayesian data mining did not detect new or unexpected safety signals. Conclusions: Findings from our safety review of ZVL are consistent with those from pre-licensure clinical trials and other post-licensure assessments. Transient injection-site reactions, HZ, and rashes were most frequently reported to VAERS following ZVL. Overall, our results are reassuring regarding the safety of ZVL.

A Case of Herpes Zoster and Meningitis in a Twice-Vaccinated Healthy Adolescent

Since the adoption of the varicella-zoster virus (VZV) vaccine, the incidence of varicella infections of all types has declined. Although uncommon, local cutaneous herpes zoster secondary to vaccine-strain VZV has been well documented in healthy children. However, there are few reports of vaccine-strain VZV central nervous system disease in this same population. We present a case of a previously healthy twice-VZV vaccinated 14-year-old girl who presented with rash and headache who was found to have herpes zoster complicated by meningitis. Cerebrospinal fluid polymerase chain reaction confirmed zoster infection secondary to reactivation of vaccine-strain VZV. Her disease course and response to therapy are reviewed.