Varicella In Children Research Articles

Estimated value of productivity lost due to childhood chickenpox in the United Kingdom: a survey of parents.

While medical costs of chickenpox have been researched, little is known about indirect costs. Understanding total costs is important for decisions about vaccination. This study estimated the value of lost productivity of adults missing work to care for children with chickenpox. It comprised an international literature review, online survey of 1,526 parents of children aged 1 to 11 years, and computation of indirect costs of chickenpox in the UK. The survey covered chickenpox episodes amongst respondents' children, time children took off school/nursery, and work absenteeism by parents/caregivers caring for them. Respondents reported on 2,283 children, of whom 52% (1185/2283) experienced chickenpox. Almost half (591/1185) missed days of school/nursery, averaging 5.6 days missed. In 260 cases of 542 adults providing data with such a child, an adult missed work to care for the child. The daily value of this lost productivity was £170. There were approximately 200,000 GP consultations for chickenpox and 625,000 births annually, suggesting annual chickenpox incidence lies between these figures. The estimated annual UK productivity loss due to chickenpox is £20 -£70 million ($25-$90 million). Annual value of lost productivity due to chickenpox is in range £20 to £70 million.

Sequence analysis of isolated strains of herpes zoster virus among patients with shingles.

Herpes zoster, or shingles, is caused by the varicella-zoster virus (VZV), which initially presents as chickenpox in children. VZV is a global health concern, especially in winter and spring, affecting 10-20% of adults over 50 and posing a 30% risk for the general population. This study used PCR to detect VZV, confirming results with duplicated DNA samples and identifying 234 bp fragments by targeting the gpB gene. This study examined 50 herpes zoster cases from October 2020 to April 2021, involving 30 males and 20 females aged 10 to 90, diagnosed by dermatologists. Data were collected via a questionnaire. PCR detected VZV by amplifying the gpB and MCP genes from skin lesion samples. Six positive 234-bp PCR products were sequenced at Macrogen Inc. in Seoul, South Korea. Six DNA samples with 234 bp amplicons were sequenced, showing 99-100% similarity to human alpha herpesvirus sequences in the gpB gene. NCBI BLAST matched these sequences to a reference (GenBank acc. MT370830.1), assigning accession numbers LC642111, LC642112, and LC642113. Eight nucleic acid substitutions caused amino acid changes in the gpB protein: isoleucine to threonine, serine to isoleucine, and threonine to Proline. These variants were deposited in NCBI GenBank as gpB3 samples. The study found high sequence similarity to known VZV sequences, identifying six nucleic acid variations and eight SNPs. Notable amino acid changes in the gpB protein were deposited in NCBI GenBank as the gpB3 sample.

Cost-Effectiveness of Varicella Vaccination for 1–4-Year-Olds in Shanghai, China

IntroductionVaricella has not yet been included in the National Immunization Program (NIP) in China, and varicella vaccination strategies vary by region. To determine the optimal varicella vaccination strategy in Shanghai, China, the cost-effectiveness and five-year costs of five immunization scenarios were analyzed. MethodsA static decision tree-Markov model was developed in 2022 to assess the cost-effectiveness and five-year costs of voluntary and routine varicella vaccination programs in the 2019 birth cohort in Shanghai from a societal perspective. Parameters were collected in 2022 from the varicella surveillance system, a questionnaire survey of 414 guardians of patients with childhood varicella, and semi-structured interviews with 20 experts on varicella outbreaks from different institutions in Shanghai. The outcomes included varicella cases avoided, quality-adjusted life year (QALY) loss, and incremental costs per QALY (ICER). The five-year costs were compared with local medical expenditures. ResultsAmong the five scenarios, one dose of routine varicella vaccination was the most cost-saving (USD 70.2) and cost-effective (Dominant) with a five-year immunization expenditure of USD 9.9 million. Two doses of routine varicella vaccination had the highest QALY (29.9), and its ICER (USD 791.9/QALY) was below the willingness-to-pay threshold (USD 5,203-23,767/QALY). The five-year immunization expenditure was USD 19.8 million. The effectiveness and price of vaccines, vaccination coverage, and per capita income are the four main factors that affect ICERs. ConclusionsIn Shanghai, the two doses of routine varicella vaccination strategy for 1- and 4-year-olds with a 95% coverage rate was found to be the optimal varicella immunization strategy.

PERIPHERAL FACIAL PARALYSIS FOLLOWING CHICKENPOX INFECTION IN ADULTS: A RARE COMPLICATION

Chickenpox is caused by the varicella-zoster virus (VZV/HHV-3), one of the eight human herpesviruses. VZV virus-associated peripheral neuropathies usually occur after shingles in adults and more rarely after chickenpox in children. Although chickenpox has a good prognosis, neurological complications such as encephalitis, acute cerebellar ataxia, myelitis, and meningitis are rarely associated with the disease. Peripheral facial paralysis (PFP) is an extremely rare complication in patients with chickenpox. We report the case of a 19-year-old woman with unilateral PFP, which developed after varicella infection, who was successfully treated with acyclovir, short-term steroids, and physical rehabilitation.

Effectiveness of the varicella vaccine in the real world, a matched case-control study

BackgroundUniversal varicella vaccination has been introduced in many countries, but there are a number of important differences in their vaccination strategies. It is essential to establish a vaccination program that can maximize the benefits of varicella vaccine, but there is a lack of comprehensive research on the effectiveness of varicella vaccine in different vaccination status. MethodsUsing data from population-based surveillance platforms we conducted a 1:2 matched case-control study. The cases were clinically diagnosed varicella with onset from 2017 to 2021, 1–14 years old in Chaoyang District, Beijing. The controls were matched according to date of birth (±1 month), sex and residence. The vaccination data of the subjects were obtained from the Childhood Immunization Information Management System in Beijing. Using conditional logistic regression models with or without interaction terms, we evaluated the effectiveness of varicella vaccine in different vaccination status. ResultsA total of 2528 cases and 5056 controls were enrolled. This study found that whether the time since last vaccination was adjusted had a substantial effect on the comparing vaccine effectiveness (VE) between subgroups. After adjustment for the time since last vaccination, 1) the incremental VE of 2-dose was 49.6 % (95 % Confidence Interval [CI], 38.8–58.6) compared with 1-dose (93.9 % vs. 88.0 %); 2) Among children who received one dose, the risk of chickenpox in children vaccinated at 18–23 months was 1.382 (95 %CI, 1.084–1.762) times that in children vaccinated at 12–17 months. 3) the VE with less than one, two, and three year intervals is higher than that with six-year-intervals (P < 0.05), respectively. ConclusionsWhen comparing VE between subgroups of different vaccination status, the time since last vaccination should be adjusted. The first dose of varicella vaccine should be given as early as the second year of life, and the second dose can improve vaccine effectiveness.

Differences and similarities between Monkeypox and Chickenpox in children during an outbreak

IntroductionHerein, we described cases of children under 16 years old suspected to be infected with Monkeypox virus (MKPV) and diagnosed with chickenpox in public hospitals of Marseille, south of France. Material and methodsWe conducted a retrospective study from March 23rd, 2022 to October 20th, 2022 in our institution of results of MKPV DNA and varicella-zoster virus (VZV) DNA detection by PCR performed on cutaneous lesions swabs collected from children <16 years old. ResultsNone of the cutaneous swabs collected from 14 children were positive for MKPV DNA. In contrast, 30/168 (17 %) cutaneous swabs collected from children were positive for VZV DNA. Of these 30 VZV-positive children, 7 had been suspected of MKPV infection because of their atypical rash, due to the location of the lesions and the chronology of their appearance. DiscussionAs in our cohort, pediatric cases of the 2022 Monkeypox outbreak in non-endemic developed countries have been very rare. This variant of MKPV does not normally spread easily and requires very close physical contact between an infected person (skin lesions, bodily fluids or respiratory droplets) and another person to be transmitted. It will nevertheless be a question of remaining vigilant as not to ignore the possibility of close contact or sexual transmission of Monkeypox in a child, or the possibility of a new and more contagious variant. ConclusionIt is difficult to differentiate Monkeypox infection from other infections associated with rashes, it is important to remember that viruses change as well as their forms of presentation.

An analysis of risk factors for visceral disseminated varicella in children.

Visceral disseminated varicella involves the internal organs, and complications such as encephalitis, hepatitis, and coagulation disorders threaten a patient's life. In this study, our aim is to analyze the risk factors for visceral disseminated varicella to enable the early identification of patients at a high risk of visceral disseminated varicella. We reviewed the medical records of children hospitalized with varicella. The data covered demographics, clinical manifestations, auxiliary examinations, treatments, and outcomes. Logistic regression was used to analyze the risk factors. A multivariate logistic regression analysis showed that abdominal pain [odds ratio (OR) 20.451, 95% CI 1.637-255.548], increased levels of C-reactive protein (OR 12.794, 95% CI 1.820-89.937), increased levels of alanine aminotransferase (OR 7.453, 95% CI 1.624-34.206), and the time between onset and antiviral therapy of more than 7 days (OR 12.451, 95% CI 1.569-98.810) were independent risk factors for visceral disseminated varicella. Patients with varicella who have the abovementioned risk factors need to be monitored for the risk of developing visceral disseminated varicella, for which timely antiviral therapy is necessary.

Rare Complication of Chicken Pox in Children - Acute Respiratory Distress Syndrome (ARDS): A Case Report

Abstract not available&#x0D; DS (Child) H J 2022; 38(2): 107-110

Prenatal Exposure to Poly- and Perfluoroalkyl Substances (2009-2014) and Vaccine Antibody Titers of Measles, Mumps, Rubella, and Varicella in Children Four to Eight Years Old from the Healthy Start Cohort.

Prenatal exposures to certain poly- and perfluoroalkyl substances (PFAS) are associated with reduced humoral responses to some childhood immunizations. We estimated associations between prenatal PFAS exposure and child antibody titers for measles, mumps, rubella (MMR), and varicella after immunization. We measured serum antibody titers of 145 children (4-8 y old) enrolled in the Healthy Start cohort in Colorado, whose mothers had PFAS quantified mid-pregnancy (2009-2014). We used linear and logistic regression models to assess the relationship between five PFAS detected in of mothers and continuous or non-high-censored ("low") antibody titers and quantile g-computation to evaluate the overall effect of the PFAS mixture. Median concentrations of individual PFAS were at or below the median reported among females in the United States. After receiving two vaccine doses, seropositive levels of antibodies were detected among most (93%-100%) children. Each log-unit increase in perfluorononanoate was associated with 2.09 [95% confidence interval (CI): 1.13, 3.87] times higher odds of a low measles titer, and each log-unit increase in perfluorooctanoate was associated with 2.46 (95% CI: 1.28, 4.75) times higher odds of a low mumps titer. Odds ratios for all other PFAS were elevated, but CIs included the null. Each quartile increase in the PFAS mixture was associated with 1.35 (95% CI: 0.80, 2.26) times higher odds of a low measles titer and 1.44 (95% CI: 0.78, 2.64) times higher odds of a low mumps titer. No significant associations were observed between PFAS and varicella or rubella antibodies. In stratified analyses, associations were negative among female children, except for perfluorohexane sulfonate and varicella, whereas they were positive among males. Some prenatal PFAS were associated with lower antibody titers among fully immunized children. The potential for immunotoxic effects of PFAS requires further investigation in a larger study, because exposure is ubiquitous globally. https://doi.org/10.1289/EHP12863.

Post-Exposure Prophylaxis for Varicella-Zoster Virus Exposure in High-Risk Children.

Post-exposure prophylaxis (PEP) with varicella immunoglobulin is recommended to minimize risk of varicella complications for high-risk children. However, providers frequently use alternatives like acyclovir or intravenous immunoglobulin. A retrospective cohort study was conducted of PEP for varicella in children from January 2009 to December 2019. Data were provided by 47 children's hospitals who participate in the Pediatric Health Information Systems database. Patients with clinical encounters for varicella exposure were reviewed. Choice of varicella PEP regimens, including differences by underlying condition and institution, and incidence of varicella disease were determined. A total of 1704 patients with first clinical encounters for varicella met inclusion criteria. Of these patients, 509 (29.9%) were prescribed PEP after varicella exposure, and 65 (3.8%) ultimately had a subsequent encounter for varicella disease. Of 509 patients who received PEP, acyclovir was most frequently prescribed (n = 195, 38.3%), followed by varicella immunoglobulin (n = 146, 28.7%), IVIG (n = 115, 22.6%), and combination therapy (n = 53, 10.4%). The highest proportion of varicella immunoglobulin use (10/20, 50%) was amongst children with diagnoses of rheumatological/gastrointestinal conditions. The highest proportion of acyclovir use (29/684, 4.2%) was amongst children with diagnoses of oncology/stem cell transplant conditions. The proportion of patients who subsequently had clinical encounters for varicella disease was highest for Acyclovir (30/195, 15.4%) followed by varicella immunoglobulin (5/146, 3.4%), combination therapy (2/53, 3.8%), and intravenous immunoglobulin alone (0/115) (P < .0001). Varicella PEP in high-risk children was highly varied among children's hospitals. In our dataset, use of acyclovir was associated with a higher rate of subsequent encounters for Varicella disease.

Trends in age-specific varicella incidences following the introduction of the general recommendation for varicella immunization in Germany, 2006–2022

BackgroundIn Germany, general childhood varicella vaccination has been recommended since 2004. A feared effect of low vaccination coverage is a possible shift in incidence from children to teenagers and young adults who are at higher risk of severe outcomes. If true, this shift would possibly necessitate changes to the national immunization strategy.We aimed to evaluate the effects of the general vaccination recommendation on age-specific varicella incidences in Germany in general and examine specifically whether a shift from children to teenagers (15 to 19 years) has occurred.MethodsTrends in age-specific incidences were evaluated using triangulation with the following datasets: national mandatory notification data (N) (2014–2022), billing data of the statutory health insurance associations (I) (2009–2017) and data from a doctor's sentinel system (S) (2006–2017). Similar clinical case definitions were used in N and S, while I used ICD-10-codes. Age groups were stratified as available in all three systems. Incidences per year were calculated based on the total population (N), the number of statutory health insured (I), and extrapolated from S to the total population.ResultsDuring all years of observation, age-specific incidences have dropped significantly across all age-groups for S und I. The age groups (under 10 years) with initially highest incidences were the ones with the strongest reductions (under 1 year: -90%, 1–4 years: -95.5%, 5–9 years: -89.2% for S; -67.7%, -78%, -79.3% for I). A single 53.1% increase in the low incidence in S among 15–19-year olds observed in 2017 compared to 2016 could not be confirmed in N or I. Increases in incidences during the first two years of N are probably due to improved notification behaviour over these years. In 2019, all age-specific incidences increased (N), with 15 to 19-year olds showing the highest relative increase (28.2%).ConclusionsSince the introduction of the general vaccine recommendation against varicella, incidences across all age-groups have declined significantly. Available data indicate no evidence for a shift in disease incidence to older age groups. Every incidence increase beyond childhood age should however be followed up closely. So far, children and adolescents have both benefitted from the current vaccination strategy.

Catch-up vaccination and enhanced immunization against hepatitis B, hepatitis A, measles, mumps, rubella and varicella in children with idiopathic thrombocytopenic purpura.

Limited data exist about the vaccination of children with idiopathic thrombocytopenic purpura (ITP) against vaccine preventable diseases. This study identified the vaccination status of children with ITP against hepatitis A, hepatitis B, measles, mumps, rubella and varicella, completed the immunization of children with inadequate immunization, re-evaluated post-vaccination antibody titers and identified probable vaccination-related complications. All of 46 children had chronic ITP were included. Seroconversion of hepatitis A, hepatitis B, varicella, measles, rubella and mumps vaccines was screened. All children with seronegative antibodies against vaccine preventable disease were given a vaccination appointment. Antibody levels were re-measured during a period ranging from 1 to 6 months. Potential complications were detected. There were 46 children with a mean age of 12.25 years. All children had chronic ITP and received intravenous immunoglobulin at least once previously. Considering the vaccination status, 50% (23 children) had vaccinations appropriate for their age, 47.8% (22 children) did not know their vaccination status and 2.2% (1 patient) did not have vaccinations. Seven children (15.2%) were seropositive for all antibody types and the remaining 39 children were scheduled for vaccination. Post-vaccination antibody titers confirmed that all children became seropositive for each disease. There was no complication in any patient. Immunization against hepatitis B, hepatitis A, measles, mumps, rubella and varicella is insufficient in a considerable number of children with ITP, Hepatitis B Virus (HBV) and Hepatitis A Virus (HAV) immunization being the most frequently inadequate. After immunization, adequate seroconversion levels were achievable without complications.

Chickenpox in Poland in 2020.

Chickenpox is an infectious disease caused by the varicella zoster virus. The characteristic feature of this virus is very high visibility of 90-95%. The most common connection is direct contact with the disease or via droplets. The United States was the first country to introduce a universal, population-based childhood varicella vaccination program in 1995. In its 25 years of implementation, this program has significantly reduced the burden of chickenpox. There was a more than 97% reduction in varicella incidence and a 90% reduction in varicella-related hospitalizations and deaths, the highest (99%) in those under the age of 20 (born after starting the vaccination programme). Chickenpox is very common in Poland. In recent years, starting from 2002, there has been an upward trend in the incidence of chickenpox, except for 2020. In 2020, a decrease in the number of cases was recorded. The aim of the study was to assess the epidemiological situation of chickenpox in Poland in 2020 and to compare it with the situation in previous years. Evaluation of the epidemiological situation of chickenpox in Poland in 2020 was based on the results of the analysis of aggregate data published in the annual bulletins: "Infectious diseases and poisonings in Poland in 2020." and "Vaccinations in Poland in 2020". In addition, recommendations from the Protective Vaccination Program for 2020 were used. In 2020, 71,567 cases of chickenpox were registered in Poland, i.e. 39.6% less than in the previous year. The incidence of chickenpox in 2020 was 186.6 per 100,000 and was lower than in 2019. The lowest incidence was recorded in the Świętokrzyskie Voivodship - 118.5/100,000, while the highest in the Kujawsko-Pomorskie Voivodeship - 263.5/100,000. Most cases concerned children aged 0-4 years (36,661). The incidence of chickenpox in men was higher than in women, and in rural areas higher than in urban dwellers. Hospitalization due to chickenpox in 2020 covered 1,368 people, which accounted for 0.51% of the total number of registered cases. In 2020, there was a decrease in the number of cases of chickenpox compared to the previous year. The lower incidence may have been the result of reduced transmission of the varicella virus due to changes in the health behavior of the population during the COVID-19 pandemic (isolation measures and the introduction of a lock down throughout Poland limiting the activity of the population).

Rapid, sensitive, and specific lateral-flow immunochromatographic point-of-care device for detection of varicella-zoster virus immunoglobulin G antibodies in fingerstick blood

Varicella zoster virus (VZV) causes childhood chickenpox, becomes latent in sensory ganglia and reactivates years later to cause shingles (Zoster) and postherpetic neuralgia in the elderly and immunosuppressed individuals. Serologic IgG tests can be used to determine if a person has antibodies to VZV from past varicella infection or had received varicella or zoster (shingles) vaccination. Commercial enzyme-linked immunosorbent assays (ELISAs) are currently used for the detection of VZV IgG antibodies in patient serum samples. However, ELISA tests require collection and processing of blood samples in a CLIA laboratory to separate serum or plasma for further testing. In this paper, we describe the development and testing of an antibody based Lateral Flow Immunochromatographic assay (LFA) device for the detection of VZV IgG in fingerstick whole blood. Analytical and clinical analyses were performed to compare the performance characteristics of the Viro VZV IgG LFA (VZV LFA) and the Diamedix VZV IgG ELISA. Analytical studies demonstrated the higher sensitivity of the VZV LFA compared to the ELISA by testing dilutions of the WHO VZV IgG serum International Standard. Clinical performance characteristics of the VZV LFA fingerstick whole blood assay were assessed at three point of care (POC) facilities by untrained users testing samples from 300 prospectively enrolled study subjects. VZV LFA results were compared with results obtained by testing serum samples obtained from the same study participants by the Diamedix VZV IgG ELISA. Two specimens with invalid results by the LFA assay were not included in the LFA performance calculations and nine equivocal ELISA results were included as positive for IgG results. The results from all three POC clinical sites demonstrated the higher sensitivity/positive percent agreement (PPA) (99.26%, 95% CI: 97.34–99.80) of the VZV LFA compared to the Diamedix VZV IgG ELISA (94.08%, 95% CI: 90.72–96.27). The specificity/negative percent agreement (NPA) of the VZV LFA compared to the ELISA test was calculated initially to be 39.29% (95% CI: 23.57–57.59) with 19 discordant test results out of 298 test results between the two assays (17 LFA positive/ELISA negative and two LFA negative/ELISA positive). The PPA and true NPA of the VZV LFA were determined by testing all 298 samples, including the discordant (19) and all concordant negative and positive (279) study subject serum samples, before and after blocking VZV gE antibody sites in the samples by spiking with VZV LFA gE capture antigen. The NPA improved to 100% (95% CI: 74.12–100) after the procedure when compared to the ELISA test results. The comparator ELISA PPA based on the spiking/blocking study remained as 94.08%, (95% CI: 90.72–96.27), comparable to test results from untreated samples.The VZV LFA has been demonstrated to be simple and sufficiently robust for use in CLIA-waived POC facilities by untrained healthcare professionals and to detect VZV IgG in 20 min from fingerstick whole blood. The VZV LFA therefore provides a fast, reliable, and highly sensitive method of determining prior VZV viral infection or varicella and zoster vaccination status.

801. IDSA Featured Oral Abstract: 25 Years of Varicella Vaccination Program in the United States: Health Impact during 1995–2019

Abstract Background In 1995, the United States was the first country to introduce universal childhood varicella vaccination. High vaccine coverage was attained among young children, ≥ 90% since 2007. In 2007, the policy was changed from 1-dose to a 2-dose program. We describe the impact of 25 years of the U.S. varicella vaccination program on varicella disease nationally. Methods We reviewed published data and analyzed overall and age-specific trends for rates from the pre-vaccine period (1990–1994) through 2019 for varicella incidence using National Notifiable Diseases Surveillance System data, hospitalizations using National Inpatient Sample data, and deaths using National Center for Health Statistics data. We present trends in persons aged &amp;lt; 50 years, which captures most varicella burden and avoids misclassified herpes zoster in older people. Outbreak (≥ 5 varicella cases epidemiologically linked) characteristics were assessed for 1995–2019 and were informed by published data and analysis of surveillance data reported to CDC. Results Within the 10 years of the 1-dose program, varicella incidence, hospitalization, and mortality rates declined dramatically (71%–90%) vs. pre-vaccine. However, limited transmission continued in school settings which informed the change to a 2-dose policy. By 2019, declines reached &amp;gt; 97% for incidence and 94% and 97% for hospitalizations and deaths, respectively. The greatest decline occurred among persons aged &amp;lt; 20 years, born during the varicella vaccination program, with 99%, 97%, and &amp;gt; 99% reduction in incidence, hospitalizations, and deaths, respectively. The 2-dose program further reduced the number, size, and duration of outbreaks vs. the 1-dose program; over the entire program, the proportion of outbreaks with &amp;lt; 10 cases increased from 28% to 73%. Conclusion The varicella vaccination program significantly reduced varicella morbidity and mortality in the U.S. Twenty-five years into the program, pediatric varicella hospitalization has become a rare event and varicella deaths in persons aged &amp;lt; 20 years are practically eliminated in the U.S. Annually, &amp;gt; 3.8 million cases, 10,500 hospitalizations, and 100 deaths from varicella are now prevented in the United States due to the varicella vaccination program. Disclosures All Authors: No reported disclosures.

Safety of varicella vaccination strategies: An overview of reviews.

The safety of new vaccines under development as well as existing vaccines is a key priority for national and international public health agencies. A number of countries have implemented universal childhood varicella vaccination programmes over the past 30years. However, strategies differ in terms of the number of doses, type of vaccine(s) recommended, age at vaccination and interval between doses for a two-dose schedule. An overview of reviews was undertaken to assess the existing systematic review evidence of the safety of varicella vaccination strategies. The review was restricted to immunocompetent children aged 9months to 6years inclusive. A comprehensive search of databases, registries and grey literature was conducted up to 2 February 2022. Two reviewers independently screened, extracted data and assessed the methodological quality of included reviews. Overlap of included reviews was also assessed. A total of 17 reviews, incorporating both the monovalent varicella only and quadrivalent measles-mumps-rubella-varicella (MMRV) vaccines were included in the overview; six assessed the safety of one-dose strategies, four assessed the safety of two-dose strategies and 14 reviews did not specify the dosing strategy. The evidence suggests that mild local and systemic reactions are relatively common with varicella vaccination. Febrile seizures are also possible adverse effects of both the monovalent and quadrivalent MMRV vaccine, but serious adverse reactions are rare. While most reviews contained methodological flaws, and analysis by vaccine type and dosing strategy was restricted due to lack of detail in reporting of the reviews, there was clear and consistent evidence from a substantial evidence base, comprising 34 randomised controlled trials and 62 other primary studies/reviews, that varicella vaccination is safe.

Features of course of chickenpox and immunization of children with congenital epidermolysis bullosa from &lt;i&gt;Varicella zoster virus&lt;/i&gt;: Results of retrospective and prospective study

Patients with congenital epidermolysis bullosa (CEB) are at increased risk of developing skin infections. In this category of patients, infection with the varicella zoster virus (VZV) can lead to such complications.Purpose of the study. To assess the severity of Varicella (VA) and the immune status of patients with CEB who had a history of VA. To study the efficacy and safety of the varicella vaccine in patients with CEB.Methods. During the study, two groups were formed: children with CEB who had a history of VO (group 1), children who received one dose of vaccine against VO (group 2). The severity of chickenpox in children from group 1 was assessed based on the survey data. The immune status of participants in groups 1 and 2 was determined by the level of serum IgG antibodies to VZV by enzyme immunoassay. The safety of immunization against varicella in children with CEB was assessed by the number of adverse events in the post-vaccination period.Results. The study included 16 children with CEB who had a history of chickenpox and 30 children with CEB who were vaccinated against chickenpox. According to the survey, in group 1 5 (31.25%) people had mild chickenpox, 8 (50.00%) children had moderate severity, and 3 (18.75%) children had a severe course of the disease. According to the results of laboratory data, in 15 (94.00%) children, a sufficient level of protective antibodies was formed after the disease. Thirty patients were immunized with the first dose of varicella vaccine. The vast majority of patients developed a level of protective antibodies to the varicella-zoster virus. All patients did not have serious adverse events and worsening of the underlying disease in the post-vaccination period.Conclusion. The data obtained indicate a good safety profile and efficacy of the first dose of the varicella vaccine and allow us to proceed with further observations after the completion of the course of immunization of children with CEB against this infection.

Clinical efficacy and effectiveness of alternative varicella vaccination strategies: An overview of reviews.

A number of countries have implemented universal childhood varicella vaccination programmes over the past 30years. However, strategies differ in terms of dosing schedule (one- or two-dose), type of vaccine(s) recommended (monovalent, quadrivalent measles-mumps-rubella-varicella, or both), age at vaccination, and dosing interval for a two-dose schedule. An overview of reviews was undertaken to assess the existing systematic review evidence of the clinical efficacy/effectiveness of alternative varicella vaccination strategies. A comprehensive search of databases, registries and grey literature was conducted up to 2 February 2022. Two reviewers independently screened, extracted data and assessed the methodological quality of included reviews. A total of 20 reviews were included in the overview; 17 assessed the efficacy/effectiveness of one-dose strategies and 10 assessed the efficacy/effectiveness of two-dose strategies. Although the quality of most reviews was deemed 'critically low', there was clear and consistent evidence that vaccination is very effective at reducing varicella. While the analysis was restricted due to lack of detail in reporting of the reviews, the evidence suggests that two-dose strategies are more efficacious/effective than one-dose strategies in preventing varicella of any severity, but that both strategies have similar high efficacy/effectiveness in preventing moderate or severe varicella. Based on this evidence in this overview of reviews, a key consideration for policymakers on the possible introduction of a childhood varicella vaccination programme and the choice between a one- or two-dose strategy, will be whether the objective of a programme is to prevent varicella of any severity or to prevent moderate to severe varicella.

National and provincial burden of varicella disease and cost-effectiveness of childhood varicella vaccination in China from 2019 to 2049: a modelling analysis

In China, varicella is the third most frequently reported vaccine-preventable infectious disease after tuberculosis and influenza, and imposes a heavy burden on families and society. To inform future immunization policy, we investigated disease burden of varicella in China and explored cost-effectiveness of different varicella vaccination strategies at national and provincial levels. A dynamic transmission model was developed to assess disease burden of varicella and the impact of varicella vaccination in China. A cost-effectiveness analysis of three alternative vaccination strategies in China's National Immunization Program (NIP) compared with no vaccination was conducted. Scenario analyses and sensitivity analyses were performed to check the robustness of the results. It was estimated that 3.35 million new varicella cases occurred in 2019, more than three times of 982 thousand cases officially reported from National Notifiable Infectious Disease Surveillance System (NNIDSS). The under-reported rate was approximately 71%. The economic analysis revealed that from the societal perspective, the incremental cost-effectiveness ratio (ICER) for one dose of varicella vaccination in NIP was US$ 2357 per QALY at the national level and it was cost-effective in 22 of 31 provinces. The ICER for one dose varicella vaccination plus a mass catch-up for unvaccinated children aged 2-11 years old would be US$-5260 per QALY, cost-saving at the national level. The one dose plus mass catch-up NIP strategy was also cost-saving in 24 of the 31 provinces. Varicella incident cases were substantially under-reported in China. Varicella vaccination in the NIP could significantly contribute to reducing the burden of varicella disease. From the societal perspective, including varicella vaccination into China's NIP was highly cost-effective at the national level and in most provinces. Bill & Melinda Gates Foundation.

Mechanism, impact, and effectiveness of herpes zoster vaccines: A comprehensive review

In the past decade, there has been increasing interest in whether a widespread childhood varicella immunization scheme may increase the age-specific incidence of herpes zoster in adults. This proposition is based on evidence that exposure to endemic varicella boosts varicella-zoster virus-specific immunity in adults and that cessation of varicella in the community would result in a decline in the T cell-mediated immunity required to maintain dormancy of varicella-zoster virus in neurons. However, numerous epidemiological studies have failed to fully explore this effect. Quantifying the efficacy of the varicella vaccine is a crucial step in understanding its benefits.