Varicella Vaccine Effectiveness Research Articles

A population database analysis to estimate the varicella vaccine effectiveness in children < 14 years in a high vaccination coverage area from 2004 to 2022

IntroductionIn the Veneto Region of Italy, universal varicella vaccination (VV) started in 2007 with a two-dose schedule at 12–15 months and 5–6 years of age achieving 90 % coverage in 2019. The study aimed at evaluating the vaccine effectiveness (VE) in children using a primary-care database MethodsThis retrospective analysis used Pedianet, a comprehensive database of 73 family paediatricians in the Veneto Region. Incidence rates (IR) of varicella were evaluated in children aged <14 years enrolled since birth, between January 2004 to April 2022. Cases were classified as breakthrough if happening beyond 42 days post-VV. Complications and prescription were evaluated. Subject were followed up from 2004 or the enrollment date, until the end of assistance/study or the first or second VV dose. Kaplan-Meier curves and log-rank tests were used to compare the varicella incidence by vaccination status. Hazard ratios of varicella infection, adjusted (aHRs) for sex, vaccinal status, age group, prematurity and socioeconomic status were estimated with Cox's regression. VE for one and two VV doses was defined as 1-aHR*. Results36,498 children, followed for 233,508 person-years from 2004 to 2022 experienced 1006 cases of varicella (13 complicated and 35 breakthrough). Younger children had a higher risk of experiencing varicella compared to children aged >7 years, irrespective of their vaccination status. Indeed, the IR increased from 5.5 to 19.5 × 1000 person-years and from 1.1 to 5.4 × 1000 person-years in unvaccinated and vaccinated children aged <12 months versus those aged 5–6 years, respectively. Varicella VE was 83.4 % and 94.7 % in those vaccinated with one and two doses. After six years, the cumulative probability of experiencing varicella was 10.7 % for unvaccinated subjects, and 2.5 % and 0.4 % for those vaccinated with one and two-doses (log-rank test, p < 0.001). ConclusionsTwo-dose schedule VV is effective in drastically reduce varicella episodes. Breakthrough varicella episodes remain rare events.

Diurnal rhythms in varicella vaccine effectiveness.

BACKGROUNDImmune processes are influenced by circadian rhythms. We evaluate the association between varicella vaccine administration time of day and vaccine effectiveness.METHODSA national cohort, children younger than 6 years, were enrolled between January 2002 and December 2023. We compared children vaccinated during morning (7:00-10:59), late morning to afternoon (11:00-15:59), or evening hours (16:00-19:59). A Cox proportional hazards regression model was used to adjust for ethnicity, sex, and comorbidities. The first varicella infection occurring at least 14 days after vaccination and a second dose administration were treated as terminal events.RESULTSOf 251,141 vaccinated children, 4,501 (1.8%) experienced breakthrough infections. Infection rates differed based on vaccination time, with the lowest rates associated with late morning to afternoon (11:00-15:59), HR 0.88, 95% CI 0.82-0.95, P < 0.001, and the highest rates with evening vaccination (16:00-19:59), HR 1.41, 95% CI 1.32-1.52, P < 0.001. Vaccination timing remained significant after adjustment for ethnicity, sex, and comorbidities. The association between immunization time and infection risk followed a sinusoidal pattern, consistent with a diurnal rhythm in vaccine effectiveness.CONCLUSIONWe report a significant association between the time of varicella vaccination and its clinical effectiveness. Similar association was observed with the COVID-19 vaccine, providing proof of concept consistent with a diurnal rhythm in vaccine effectiveness.

Effectiveness of two-dose vs. one-dose varicella vaccine in children in Shanghai, China: a prospective cohort study.

Varicella, a highly contagious viral disease caused by the varicella-zoster virus (VZV), affects millions globally, with a higher prevalence among children. After the initial infection, VZV lies dormant in sensory ganglia and has the potential to reactivate much later, causing herpes zoster (HZ). Vaccination is one of the most effective methods to prevent varicella, and the two-dose varicella vaccine (VarV) regimen is widely used around the world. In China, the VarV has been included in the national immunization programme with a recommended single-dose regimen. This study aimed to compare the effectiveness of the two-dose vs. one-dose VarV regimen in children in Shanghai, China. A prospective cohort study was conducted in Shanghai, China, from September 2018 to December 2022. The study enrolled children aged 3-18 years who had received either the one-dose, two-dose, or 0-dose VarV regimen. Vaccination history, varicella infection status, and relevant variables, including demographic information (name, date of birth and sex) and medical history (clinical features of varicella and illness duration) were collected through medical record review and parental interviews. A total of 3,838 children were included in the study, with 407 in the 0-dose regimen group, 2,107 in the one-dose regimen group and 1,324 in the two-dose regimen group. The corresponding incidence density in these groups was 0.13, 0.05 and 0.03 cases per 1,000 person-days, respectively. The adjusted vaccine effectiveness (VE) was 81.7% (95%CI: 59.3-91.8%) for the two-dose regimen and 60.3% (95%CI: 29.3-77.7%) for the one-dose regimen, compared to the 0-dose regimen. The two-dose VarV regimen showed a protective effectiveness of 47.6% (95%CI: 2.5-71.9%) compared to the one-dose VarV regimen. This study provides evidence supporting the greater effectiveness of the two-dose VarV regimen in preventing varicella infection compared to the one-dose regimen.

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.

Varicella vaccine effectiveness evaluation in Wuxi, China: A retrospective cohort study.

Varicella is a vaccine-preventable infectious disease. Since 1 December 2018, the varicella vaccine has been included in the local Expanded Programme on Immunization (EPI) in Wuxi, China, and children born after 1 December 2014 are eligible for free vaccination. To evaluate the effect of varicella vaccination in Wuxi city, we selected 382397 children born from 2012 to 2016 as subjects. Their disease data were obtained from the Chinese Disease Prevention and Control Information System, and their vaccination data were obtained from the Jiangsu Province Vaccination Integrated Service Management Information System. The incidence of breakthrough varicella cases increased in the first 4years and reached the peak in the fifth year. With the increase of vaccination rate, the incidence of varicella decreased significantly. The vaccine effectiveness (VE) was found to be 88.17%-95.78% for one dose and 98.65%-99.93% for two doses. Although the VE per dose decreased from 99.57% in the first year to 93.04% in the eighth year, it remained high. These findings confirmed the effectiveness of varicella vaccination in children, supported the use of a two-dose varicella vaccination strategy to achieve better protection, and provided important insights into the optimal vaccination strategy for varicella prevention in children.

Real-World Effectiveness of the Varicella Vaccine among Children and Adolescents in Qatar: A Case-Control Study.

Despite the availability of a highly efficacious vaccine, varicella outbreaks are still being reported globally. In this study, we evaluated the real-world effectiveness of varicella vaccination among children between the ages of 1 and 18 years old during the period 2017 to 2019 in Qatar. A matched case-control study was conducted that included all reported varicella-infected children who visited the primary healthcare system in Qatar from January 2017 to December 2019. The cases were children under the age of 18 years who were clinically diagnosed with varicella. The controls were of the same age, who visited the Primary Health Care Corporation (PHCC) during 2017-2019 with a skin rash where varicella infection was ruled out. The data on varicella vaccination for each participant were obtained from the electronic database in the PHCC during the study period. We included 862 cases of varicella and 5454 matched controls, with a median age of 8 years (IQR 3-12); 47.4% were female and almost 50% were of Qatari nationality. The year 2019 had the highest varicella infection count with a total of 416 cases. The cases were less likely to be vaccinated against varicella, with approximately a quarter (25.6%) of cases and 36.7% of the controls having either one or two doses of the vaccine (p < 0.001). Compared to not being vaccinated, a single dose vaccination showed a 56% reduction in the odds of varicella infection [OR 0.44, 95% CI: 0.34-0.55; p < 0.000], and a two-dose vaccination showed an 86% reduction in the odds of varicella infection [OR 0.13, 95% CI: 0.06-0.29; p < 0.000]. In this multicultural setting, a two-dose varicella vaccination shows reasonable protection against varicella infection.

The epidemiology of varicella and effectiveness of varicella vaccine in Ganyu, China: a long-term community surveillance study

BackgroundThe real-world data of long-term protection under moderate vaccination coverage is limited. This study aimed to evaluate varicella epidemiology and the long-term effectiveness under moderate coverage levels in Ganyu District, Lianyungang City, Jiangsu Province.MethodsThis was a population-based, retrospective birth cohort study based on the immunization information system (IIS) and the National Notifiable Disease Surveillance System (NNDSS) in Ganyu District. Varicella cases reported from 2009 to 2020 were included to describe the epidemiology of varicella, and eleven-year consecutive birth cohorts (2008–2018) were included to estimate the vaccine effectiveness (VE) of varicella by Cox regression analysis.ResultsA total of 155,232 native children and 3,251 varicella cases were included. The vaccination coverage was moderate with 37.1%, correspondingly, the annual incidence of varicella infection increased 4.4-fold from 2009 to 2020. A shift of the varicella cases to older age groups was observed, with the peak proportion of cases shifting from 5–6 year-old to 7–8 year-old. The adjusted effectiveness of one dose of vaccine waned over time, and the adjusted VE decreased from 72.9% to 41.8% in the one-dose group.ConclusionsThe insufficient vaccination coverage (37.1%) may have contributed in part to the rising annual incidence of varicella infection, and a shift of varicella cases to older age groups occurred. The effectiveness of one dose of varicella vaccine was moderate and waned over time. It is urgent to increase varicella vaccine coverage to 80% to reduce the incidence of varicella and prevent any potential shift in the age at infection in China.

Assessing vaccine effectiveness for varicella in Wuxi, China: a time-series analysis

Objective The varicella vaccine is not included in the national childhood immunization schedules in China. Varicella epidemics and outbreaks are frequently reported, and the evidence for the effectiveness of the varicella vaccine remains unclear. The aim of this study was to investigate varicella vaccine effectiveness in Wuxi, China. Methods Varicella surveillance data were extracted from the China Information System for Disease Control and Prevention, and vaccination data were obtained from the Vaccination Integrated Service Management Information System of Jiangsu Province, China. Time-series analysis approaches were used to estimate varicella vaccine effectiveness. Results A total of 16,093 varicella cases among children aged 1–6 years between January 2016 and December 2020 were analysed. A total of 217,297 children completed a two-dose varicella vaccination series. Compared with districts with lower vaccination rates, districts in Wuxi with higher varicella vaccination rates had a lower proportion of cases (p < 0.001). In the time-series approach, 0.8% fewer varicella cases were associated with a 1% increase in the two-dose varicella vaccination rate (p < 0.001), and similar effects were found in both the male and female populations. Conclusions Two-dose varicella vaccination was recommended as an effective health intervention to prevent varicella in Wuxi, China. Varicella vaccination is urgently needed in routine childhood immunisation programs.

Effect of the varicella vaccination on the clinical characteristics of herpes zoster cases aged 20 years and under

To discuss the effect of varicella vaccination on the clinical characteristics of herpes zoster (shingles) cases aged 20 years and under, and analyze its clinical features. Based on the Yichang Health Big Data Platform, a descriptive study was conducted to collect the information of cases aged 20 years and under in three medical institutions of Yichang Central People's Hospital, Yichang First People's Hospital and Yichang Second People's Hospital from March 2019 to September 2020. According to the history of varicella vaccine, cases were divided into vaccination group and non-vaccination group, and their clinical features and outcomes were compared. The results showed that 46 shingles cases, aged from 7 to 20 years old, were included in this study. 26 males (56.5%), 20 females (43.5%), 15 cases in vaccination group (32.6%) and 31 cases in non-vaccination group (67.4%). 28 cases had thoracic involvement, followed by lumbar (n=8), cranial (n=7) involvements and extremities (n=7). The spread of herpes skin area: 2 cases involved too large area, 21 cases of 10 cm×10 cm, 14 cases of 5 cm×5 cm, 9 cases of 1 cm×1 cm. Herpes number: 26 cases had 10-49 herpes, followed by <10 herpes (n=9), uncountable herpes (n=7) and 50-99 herpes (n=4). The clinical course[M(Q1,Q3)] lasted 20.5 (13.5,24.8) d averagely, 5 cases had postherpetic neuralgia (PHN) and 1 case had respiratory complications. Shingles decrustation time was significantly shorter in vaccination group (Z=-2.01, P<0.05), and there was no significant difference in other characteristics by vaccination. In conclusion, the number and spread of shingles in most children and adolescents are less, and the complications such as PHN are less. Varicella vaccination can reduce the decrustation time and relieve shingles cases with some clinical symptoms.

Safety and immunogenicity of the live-attenuated varicella vaccine in pediatric solid organ transplant recipients: A systematic review and meta-analysis

This study aimed to synthesize the available evidence on the immunogenicity, safety, and effectiveness of live-attenuated varicella vaccine in solid organ transplant recipients. Medline and EMBASE were searched using predefined search terms to identify relevant studies. The included articles reported varicella vaccine administration in the posttransplant period in children and adults. A pooled proportion of transplant recipients who seroconverted and who developed vaccine-strain varicella and varicella disease was generated. Eighteen articles (14 observational studies and 4 case reports) were included, reporting on 711 transplant recipients who received the varicella vaccine. The pooled proportion was 88.2% (95% confidence interval 78.0%-96.0%, 13 studies) for vaccinees who seroconverted, 0% (0%-1.2%, 13 studies) for vaccine-strain varicella, and 0.8% (0%-4.9%, 9 studies) for varicella disease. Most studies followed clinical guidelines for administering live-attenuated vaccines, with criteria that could include being at least 1 year posttransplant, 2 months postrejection episode, and on low-dose immunosuppressive medications. Varicella vaccination in transplant recipients was overall safe in the included studies, with few cases of vaccine-strain-induced varicella or vaccine failure, and although it was immunogenic, the proportion of recipients who seroconverted was lower than that seen in the general population. Our data support varicella vaccination in select pediatric solid organ transplant recipients.

The Protective Effectiveness of 2-Dose Varicella Vaccination in Children in Korea: A Case-Control Study.

A 2-dose vaccination against varicella has been adopted in many places; however, it has not been widely introduced in Korea. This study aimed to assess 1-dose and 2-+dose vaccine effectiveness (VE) against laboratory-confirmed varicella in Korea to provide a scientific basis for developing an immunization strategy. We constructed a national cohort using national surveillance data and the national immunization registry. From the cohort, we conducted a 1:2 matched nested case-control study to estimate and compare the VE of the 1-dose and 2-dose of varicella vaccination using exact conditional logistic regression. VE was calculated as [1 - matched odds ratio (OR) × 100%]. From January 1, 2011 to December 31, 2020, a total of 205,173 varicella cases were reported to the notifiable diseases surveillance system. Of these, we included 4,387 laboratory-confirmed varicella cases and 8,774 controls for the analyses. The VE of 1-dose vaccination was 16.8% (95% CI: -9.0% to 36.5%), whereas the VE of 2-doses of the vaccination was 98.6% (95% CI: 96.0%-99.5%). These findings suggest that the 2-dose vaccination strategy can be an effective strategy to prevent varicella.

Impact assessment of immunization and the COVID-19 pandemic on varicella across Europe using digital epidemiology methods: A descriptive study.

Varicella is usually a mild disease in children but may be life-threatening, especially in adolescents and adults. Infection control measures implemented during the Coronavirus Disease 2019 (COVID-19) pandemic may have suppressed varicella transmission, potentially creating an 'immunity debt', particularly in countries without universal varicella vaccination. To assess trends in Google search engine queries for varicella keywords as a proxy for varicella infection rates and to evaluate the effect of universal varicella vaccination on these trends. A further objective was to assess the impact of the COVID-19 pandemic on varicella keyword search query trends in countries with and without universal varicella vaccination. This study used the keyword research tool, Google Trends, to evaluate trends in time series of the relative search query popularity of language-specific varicella keywords in 28 European countries from January 2015 through December 2021. The Google Ads Keyword Planner tool was used to evaluate absolute search volumes from March 2018 through December 2021. The relative search query popularity of varicella keywords displayed marked seasonal variation. In all 28 countries, the relative search query popularity of varicella keywords declined after the start of the COVID-19 pandemic (March 2020), compared with pre-pandemic levels (range, -18% to -70%). From April 2020 to July 2021, a period of intense COVID-19 transmission and infection control, absolute search volumes for varicella keywords were lower than pre-pandemic levels but rebounded after July 2021, when infection control measures were relaxed. This evaluation of search query trends demonstrated that search query data could be used as a proxy for trends in varicella infection rates and revealed that transmission of varicella may have been suppressed during the COVID-19 pandemic. Consideration should be given to using search query data to better understand the burden of varicella, particularly in countries where surveillance systems are inadequate.

Effectiveness of varicella vaccination during an outbreak in a large one-dose-vaccinated population in Shanghai

ABSTRACT Emergency vaccination (EV) is used as effective postexposure prophylaxis (PEP) to control varicella outbreaks within 3–5 days. However, the advantages of a second dose of varicella vaccine (VarV) in students who had received one dose before an outbreak and the potential benefits of EV at more than 5 days after exposure have not been fully evaluated. This study evaluated the vaccine effectiveness (VE) of EV in preventing disease development during a varicella outbreak in Shanghai, China, in 2020. Questionnaires were used to obtain student demographic information, clinical manifestations, varicella history, vaccination status, and willingness to receive EV. The VE of EV was calculated as [1-relative risk (RR)] ×100%. Among the 1455 students included in this study, 31 cases were identified, resulting in an overall attack rate of 2.13%. There were 6 cases in unvaccinated students and 25 cases in one-dose-vaccinated students. A total of 788 students received one EV dose. The attack rates were 6.38% (6/94), 4.26% (19/446), 2.82% (2/71), and 0.56% (4/717) among unvaccinated students, students who received 1 dose of VarV, and students who received EV with the 1st and 2nd dose of VarV, respectively. Compared to that in unvaccinated students, the VE of EV with the 2nd dose of VarV was 88% (95% CI 49% to 97%). EV should be performed as soon as possible after exposure. Nevertheless, vaccination is still recommended at more than 5 days post exposure to control varicella outbreaks.

The Effectiveness of Varicella Vaccine: 25 Years of Postlicensure Experience in the United States.

We summarize studies of varicella vaccine's effectiveness for prevention of varicella and lessons learned during the first 25 years of the varicella vaccination program in the United States. One dose of varicella vaccine provided moderate protection (82%-85%) against varicella of any severity and high protection (100%) against severe varicella, with some waning of protection over time. The 1-dose program (1995-2006) had a substantial impact on the incidence both of varicella and of severe outcomes (71%-90% decrease) although it did not prevent low-level community transmission and some outbreaks continued to occur in highly vaccinated populations. Two doses of varicella vaccine improved the vaccine's effectiveness by at least 10% against varicella of any severity, with further declines in the incidence both of varicella and of severe outcomes as well as in both number and size of outbreaks. There is no evidence for waning of the effectiveness of 2 doses of the vaccine.

Epidemiological Characteristics of Varicella under Different Immunisation Strategies in Suzhou Prefecture, Jiangsu Province.

Background: The varicella vaccine is excluded from the Chinese national immunisation programme but is included in the local expanded programme on immunisation (EPI) in the Suzhou Prefecture. This study investigated the epidemiological characteristics of the varicella cases during the implementation of different immunisation strategies in the Suzhou Prefecture, Jiangsu Province. Methods: In this study, we used descriptive statistics. Information on reported instances from 2012 to 2021 was first retrieved. Data on varicella cases were collected from the China Information System for Disease Control and Prevention (CISDCP). Similarly, information on vaccinated children was obtained from the Jiangsu Province Vaccination Integrated Service Management Information System (JPVISMIS). The census data in this study was procured from the Suzhou Bureau of Statistics. Results: From 2012 to 2021, a total of 118,031 cases of varicella were reported in Suzhou, and the average annual reported incidence was 91.35 per 100,000. The average yearly incidence after implementing the two-dose varicella vaccination decreased by 41.57% compared with the implementation of one dose. This study demonstrates two annual incidence peaks, a small peak between April and July and a prominent peak between October and January. It is also possible that this seasonal distribution is related to the geography of Suzhou. The average annual reported incidence between districts with a statistically significant difference (χ2 = 98.077, p < 0.05). The one-dose varicella vaccination coverage gradually increased from 55.34% in 2012 to 89.06% in 2021 and the two-dose varicella vaccination coverage gradually increased from 0.27% in 2012 to 82.17% in 2021. Conclusions: Administering the varicella vaccine in the local EPI has significantly decreased the incidence rate and the total number of cases. A two-dose vaccination schedule is still the best vaccination strategy for varicella vaccine effectiveness.

Vaccine Coverage and Effectiveness in a School-Based Varicella Outbreak in Jinan Prefecture, Shandong Province.

Background: Licheng District of Jinan Prefecture reported a school-based varicella outbreak. We conducted an investigation to analyze the epidemiology and scope of the outbreak, determine varicella vaccine coverage on the school campus, and estimate varicella vaccine effectiveness (VE). Methods: In the epidemiological investigation, we determined the attack rate, the clinical manifestations of varicella cases, and histories of prior varicella disease and varicella vaccination. We tested students for presence of serum IgM antibodies, and we attempted to isolate the varicella virus from vesicular fluid samples. We used chi-square to compare incidences between classes and floors. VE was estimated using a retrospective cohort study. Results: There were 13 varicella cases in the outbreak. All were among fourth grade students - twelve in Class 7 and one in Class 6. The attack rate in the two classrooms was 14.3% (13/91). Clinical symptoms were rash (100%) and fever (46.15%). All cases were reported within one average incubation period, and the epidemic curve suggested common exposure. Six of the 13 cases previously received one dose of varicella vaccine with a median time between vaccination and infection of 9 years; the other seven cases had not been vaccinated. Varicella vaccine coverage with one or more doses was 81.31%; 2-dose coverage was 38.15%. The median age of receipt of dose 1 was 1.18 years, and median age for receiving dose 2 was 5.12 years. One-dose varicella VE was 73.2% (95% confidence interval: 37.0%, 88.6%), and two-dose VE was 100%. Conclusions: Varicella vaccine coverage has been gradually increasing in recent years, as ≥1-dose and 2-dose coverage rates are higher in younger children than older children. High one-dose vaccination coverage limited the outbreak scope and led to the breakthrough cases being mild. Mild cases were difficult to detect in a timely manner. Varicella vaccine was highly effective, with 1-dose VE of 73% nine years after vaccination and 2-dose VE of 100%. We strongly recommended that all school students receive two doses of varicella vaccine.

Cost effectiveness and budget impact of universal varicella vaccination in Russia

ABSTRACT This economic evaluation assesses the cost-effectiveness and budget impact of introducing a two-dose varicella vaccine in the Russian national immunization program. A static Markov model followed a simulated 2019 Russian cohort over its lifetime and compared outcomes and costs of three varicella vaccination strategies: strategy I (doses given at 12 and 15 months of age), strategy II (doses given at 1 year and 6 years of age), and a no vaccination scenario. Inputs on age-dependent clinical pathways, associated costs, and related health outcomes were collected from national sources and published literature. Results are presented as incremental cost-effectiveness ratio (ICER) from the healthcare payer and societal perspective over the lifetime of the birth cohort and the budget impact over a 10 years’ time horizon. Vaccination strategies I and II resulted in an ICER of approximately 1.7 million rubles per quality-adjusted life years gained from the healthcare payer perspective and were cost-saving from the societal perspective. From the healthcare payer perspective, the costs per varicella case averted were 5,989 and 7,140 rubles per case for strategies I and II, respectively. However, from the societal perspective, vaccination is a dominant strategy and the budget impact analysis shows significant healthcare savings over 10 years, with strategy I realizing savings of ~2 billion rubles more than strategy II. From a public health impact perspective, varicella vaccination of children at 12 and 15 months of age through the Russian NIP is expected to be cost-effective with an affordable budget impact compared to no vaccination.

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

&lt;p&gt;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。&lt;/p&gt; &lt;p&gt;&amp;nbsp;&lt;/p&gt;&lt;p&gt;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.&lt;/p&gt; &lt;p&gt;&amp;nbsp;&lt;/p&gt;

Effectiveness of varicella vaccine as post-exposure prophylaxis: a meta-analysis

ABSTRACT Background To evaluate the effectiveness of varicella vaccine (VarV) as post-exposure prophylaxis (PEP) among children during varicella outbreaks. Material and Methods A comprehensive literature search was performed in PubMed, Embase, Web of Science, SinoMed, Wanfang and CNKI. Relevant outcomes included the incidence of varicella. Pooled estimates were calculated using a fixed-effects or random-effects model according to the heterogeneity among studies. Results A total of 15 studies with 7,474 children that received one or two dosages of VarV as PEP and 183,827 children who received no VarV were included in the meta-analysis. In total, one-dose and two-dose VarV as PEP had 43% (95% confidence interval (CI):27%, 55%) and 60% (95%CI: 35%, 75%) efficacy, respectively. When PEP was applied within 3 days, the pooled VarV as PEP for prevention of varicella was 80% (95%CI: 68%, 88%); when PEP was administered beyond 3 days, the pooled VarV as PEP for the prevention of varicella was 50% (95%CI: 11%, 72%). If the PEP was implemented with a coverage of more than 80%, the VarV could prevent 82% of varicella cases from occurring (95%CI: 15%, 96%); if the PEP covered a maximum of 80% of the susceptible cases, the VarV could prevent 65% of varicella cases from occurring (95%CI: 50%, 76%). Conclusion The two-dose VarV had better efficacy than one-dose VarV in the control of varicella outbreaks, especially if PEP was applied within 3 days of an outbreak and in conjunction with a high coverage rate ≥80%.

Effect of universal varicella vaccination and behavioral changes against coronavirus disease 2019 pandemic on the incidence of herpes zoster

BackgroundSince 2014, universal varicella vaccination has reduced the varicella and herpes zoster (HZ) incidence in vaccine recipients and increased the incidence in the child-rearing generation until 2017. ObjectiveThis study aimed to understand the future epidemiologic trends of HZ after the disappearance of varicella epidemics and during the coronavirus disease 2019 (COVID-19) pandemic. MethodsThe Miyazaki Dermatologist Society has been monitoring and analyzing the incidence of HZ patients after universal vaccination since 1997. ResultsThe HZ incidence in Oka varicella vaccine recipients aged 0–4 years decreased with the reduction in chickenpox incidence. The HZ incidence among those aged 5–9 years increased between 2015 and 2017 and decreased thereafter. From 2014–2020, the HZ incidence continued to increase to 36.6%, 51.3%, 70.2%, 56.7%, and 27.3% among those aged 10–19, 20–29, 30–39, 40–49, and 50–59 years, respectively. The HZ incidence in patients aged ≥ 60 years increased by 2.3% annually from 2014 to 2020, corresponding to an annual 2% increase since 1997, and was unaffected by varicella epidemics. COVID-19 infection control measures, lifestyle changes and the resulting stress did not affect the HZ incidence in 2020. ConclusionUniversal varicella vaccination eliminated varicella epidemics, and HZ was reduced in vaccine recipients. The HZ incidence for those aged 10–59 years increased from 2014 to 2020, in contrast to those aged ≥ 60 years, which is attributable to booster immunity expiration due to varicella contact in this age group.