Chickenpox in Poland in 2019

BACKGROUND

Chickenpox is a common disease in Poland, which is usually mild, but can lead to serious complications. Vaccination is an effective form of prevention. Prior to universal vaccination against chickenpox, high incidence was recorded in many countries. In Poland, since 2003, vaccinations have been carried out recommended for people who did not suffer from chickenpox and, since 2009, obligatory vaccinations for children up to 12 years of age particularly vulnerable to infection and children around them.

AIM

To assess epidemiological situation of chickenpox in Poland in 2019, including vaccination coverage in Polish population, in comparison to previous years.

METHODS

Assessment of the epidemiological situation of chickenpox in Poland in 2019 was based on the results of the analysis of aggregate data published in the annual bulletins: "Infectious diseases and poisoning in Poland in 2019" and "Protective Vaccination in Poland in 2019." In addition, the recommendations from the Protective Vaccine Program for 2019 were used.

RESULTS

In 2019, 180 641 cases of chickenpox were registered in Poland, i.e. 17.2% more than in the previous year. The incidence of chickenpox in 2019 was 470.6 per 100 thousand and was higer than in 2018. The lowest incidence was registered in the Dolnośląskie Voivodeship - 297.9/100 thousand, the highest in the Śląskie Voivodeship - 555.9/100 thousand. Children aged 0-4 years became ill the most (89 611). The incidence of chickenpox in men was higher than in women, and in rural areas it was higher than in urban areas. Hospitalization due to chickenpox in 2019 covered 1 156 people, which accounted for 0.64% of the total number of registered cases.

SUMMARY

In 2019, there was a growth in the number of chickenpox cases compared to the previous year, the incidence remains lower than in 2012-2014. An effective method of disease prevention is vaccination against chickenpox, which, despite the lack of common funding, is carried out in a growing population. Further improvement of the epidemiological situation requires health education of the society in the field of primary prevention, which is based on vaccinations. As recommended, the chickenpox vaccination course consists of two doses of the vaccine separated by at least 6 weeks from the previous dose.

What We Know Now: An Economic Evaluation of Chickenpox Vaccination and Dose Timing Using an Agent-Based Model

OBJECTIVES

The value of chickenpox vaccination is still debated in the literature and by jurisdictions worldwide. This uncertainty is reflected in the inconsistent uptake of the vaccine, where some countries offer routine childhood immunization programs, others have targeted programs, and in many the vaccine is only privately available. Even across the countries that have universal funding for the vaccine, there is a diversity of schedules and dosing intervals. Using an agent-based model of chickenpox and shingles, we conducted an economic evaluation of chickenpox vaccination in Alberta, Canada.

METHODS

We compared the cost-effectiveness of 2 common chickenpox vaccination schedules, specifically a long dosing interval (first dose: 12 months; second dose: 4-6 years) and a short dosing interval (first dose: 12 months; second dose: 18 months).

RESULTS

The economic evaluation demonstrated a shorter dosing interval may be marginally preferred, although it consistently led to higher costs from both the societal and healthcare perspectives. We found that chickenpox vaccination would be cost-saving and highly cost-effective from the societal and healthcare perspective, assuming there was no impact on shingles.

CONCLUSION

Chickenpox vaccine was cost-effective when not considering shingles and remained so even if there was a minor increase in shingles following vaccination. However, if chickenpox vaccination did lead to a substantial increase in shingles, then chickenpox vaccination was not cost-effective from the healthcare perspective.

Pox Parties for Grannies? Chickenpox, Exogenous Boosting, and Harmful Injustices

Some societies tolerate or encourage high levels of chickenpox infection among children to reduce rates of shingles among older adults. This tradeoff is unethical. The varicella zoster virus (VZV) causes both chickenpox and shingles. After people recover from chickenpox, VZV remains in their nerve cells. If their immune systems become unable to suppress the virus, they develop shingles. According to the Exogenous Boosting Hypothesis (EBH), a person's ability to keep VZV suppressed can be 'boosted' through exposure to active chickenpox infections. We argue that even if this hypothesis were true, immunization policies that discourage routine childhood varicella vaccination in order to prevent shingles for other people are unethical. Such policies harm children and treat them as mere means for the benefit of others, and are inconsistent with how parents should treat their children and physicians should treat their patients. These policies also seem incompatible with institutional transparency.

Post-marketing surveillance of adverse events following measles, mumps, rubella and varicella (MMRV) vaccine: retrospecive study in apulia region (ITALY), 2009-2017

Since 2006, some Italian Regions introduced the active offer of measles, mumps, rubella, and varicella (MMRV) vaccine for all newborns during the second years of life. In 2011, Italian Drug Authority (AIFA) recommended the discontinuation of the MMRV use for an increased risk of febrile seizures following vaccination; furthermore, some Regions (such as Apulia, that introduced MMRV offer in 2009) chose to continue the use of MMRV and Ministry of Health recommended to guarantee supplemental monitoring of safety of the vaccine. In Italy, the surveillance of Adverse Events following immunization (AEFIs) is currently carried out by AIFA and Regional Health Authorities; this paper aims to summarize the results of MMRV-vaccine surveillance of AEFIs program carried out in Apulia. From the AIFA database, we selected MMRV AEFIs that occurred in Apulia (about 4,000,000 inhabitants) from 2009 to 2017. For serious AEFIs, we applied the WHO causality assessment algorithm, using for cases hospitalized information from individual medical records. In the 8 years of observation, 155 MMRV-AEFIs (reporting rate: 37.9×100,000 doses) occurred of which 26 were classified as serious (6.3×100,000 doses) and 22 led to hospitalization. Performing causality assessment, for 10 the classification was "consistent causal association to immunization" (reporting rate: 2.4×100000 doses), for 2 indeterminate, for 13 "inconsistent causal association to immunization" and for 1 not-classifiable. No case of febrile seizure resulted consistent to vaccination. All consistent serious AEFIs were completely resolved at subsequent follow-up.

[Revised multidisciplinary guidelines 'Varicella'; broader indication for post-exposure prophylaxis]

Post-exposure prophylaxis (PEP) with varicella zoster immunoglobulins (VZIG) should be administered as soon as possible after exposure to the virus, but always within ten days; in the previous guidelines this was within 96 hours. In cases of perinatal exposure, PEP with VZIG should be administered to neonates if the mother develops clinical chickenpox between seven days before delivery and seven days after delivery; in the previous guidelines this was between five days before delivery and two days after delivery. A new chapter on the treatment of chickenpox has been added to the guidelines.

Incidence of herpes zoster among varicella-vaccinated children, by number of vaccine doses and simultaneous administration of measles, mumps, and rubella vaccine

INTRODUCTION

Children may receive measles-mumps-rubella (MMR) and varicella (VAR) vaccines separately or as measles-mumps-rubella-varicella (MMRV). We examined whether pediatric herpes zoster (HZ) incidence varied by pattern of varicella vaccine administration.

METHODS

In six integrated health systems, we examined HZ incidence among children turning 12 months old during 2003-2008. All received varicella and MMR vaccines on recommended schedules. Cases were identified through 2014 using ICD-9 codes. Incidence was examined by number of varicella vaccine doses and same-day MMR.

RESULTS

Among 199,797 children, overall HZ incidence was 18.6/100,000 person-years in the first-dose MMR + VAR group, 17.9/100,000 person-years in the MMRV group, and 7.5/100,000 person-years in the VAR-alone group. HZ incidence was lower following the second dose than before the second dose in all first-dose groups.

CONCLUSIONS

HZ incidence was not meaningfully different between the MMRV and MMR + VAR first-dose groups. Overall and within first-dose groups, HZ incidence was lower among children receiving two varicella vaccine doses.

Varicella vaccine dose depended effectiveness and waning among preschool children in Hong Kong

In Hong Kong, universal varicella vaccination was introduced in July 2014 with a two-dose schedule but the vaccines had been available in the private market since 1996. With data from varicella notification and surveys on immunization coverage, we used the screening method to estimate dose-specific varicella vaccine effectiveness (VE) among preschool children in Hong Kong before universal vaccination. We estimated the VE of one- and two-dose varicella vaccination against all notified varicella as 69.4% (95% confidence interval (95% CI) 69.5-71.2) and 93.4% (95% CI 91.7-94.7), respectively. We found that VE did not decrease with time since receipt. Varicella vaccine was more effective against complications (85.4% [95% CI 48.8-95.8] for one dose and 100% [95% CI -Inf to 100] for two doses) and against hospital admission (75.2% [95% CI 53.4-86.8] for one dose and 93.1% [95% CI 47.1-99.1] for two doses). Lower protection of one-dose varicella vaccine resulted in breakthrough varicella. Under universal vaccination, second-dose varicella vaccine (given as combined measles, mumps, rubella and varicella vaccine) was first scheduled for children when they reach primary one (about 6 years of age) and was recently advanced to 18 months of age. Shortening the interval between the first dose and second dose of varicella vaccination should reduce breakthrough varicella and outbreaks in preschool.

Fifteen-minute consultation: Prevention and treatment of chickenpox in newborns

There are inconsistencies in how newborns are managed following exposure to varicella, ranging from reassurance and observation to administration of varicella zoster immunoglobulin (VZIG) and admission to hospital for varying length courses of intravenous aciclovir.Hospitalised preterm babies exposed to varicella should receive VZIG. Administration can otherwise be limited to pregnant non-immune women or to newborns if there is development of maternal chickenpox from 5 days prior to delivery up to 48 hours postdelivery. Intravenous aciclovir is only recommended in cases of newborn disease despite VZIG or in severe disease. The use of VZIG may not prevent varicella but may reduce severity of disease.In this article, we review the evidence for risk to non-immune mothers, the fetus and newborns who had different types of exposure to varicella, with recommendations for management and treatment of confirmed neonatal chickenpox.

Women who received varicella vaccine versus natural infection have different long-term T cell immunity but similar antibody levels

BACKGROUND

Varicella-zoster virus (VZV) infection during pregnancy is associated with serious fetal anomalies. The live-attenuated VZV vaccine was approved in 1995, so many vaccinated women are now of childbearing age. The question of long-term immunity to varicella is critical because breakthrough chickenpox can occur after vaccination.

OBJECTIVE

To compare humoral and T cell immunity between women of childbearing age who were immunized by vaccination or chickenpox disease.

STUDY DESIGN

Non-pregnant females between 18 and 36 years old with a history of VZV immunization (n = 20) or prior chickenpox disease (n = 20) were recruited. IgG antibody titers and T cell responses were measured by flow cytometry-based methods in serum and peripheral blood, respectively.

RESULTS

There were no significant differences in median antibody titers between vaccinated and chickenpox groups (p = 0.34). The chickenpox group had significantly higher levels of VZV antigen-specific CD4 T cells (p = 0.004).

CONCLUSION

Natural infection induced higher VZV-specific T cell immune responses than vaccination.

Frequency and cost of live vaccines administered too soon after prior live vaccine in children aged 12 months through 6 years, 2014-2017

OBJECTIVE

To identify number of children who received live vaccines outside recommended intervals between doses and calculate corrective revaccination costs.

METHODS

We analyzed >1.6 million vaccination records for children aged 12 months through 6 years from six immunization information system (IIS) Sentinel Sites from 2014-15 when live attenuated influenza vaccine (LAIV, FluMist® Quadrivalent) was recommended for use, and from 2016-17, when not recommended for use. Depending on the vaccine, insufficient intervals between live vaccine doses are less than 24 or 28 days from a preceding live vaccine dose. Private and public purchase costs of vaccines were used to determine revaccination costs of live vaccine doses administered during the live vaccine conflict interval. Measles, mumps, rubella (MMR), varicella, combined MMRV, and LAIV were live vaccines evaluated in this study.

RESULTS

Among 946,659 children who received at least one live vaccine dose from 2014-15, 4,873 (0.5%) received at least one dose too soon after a prior live vaccine (revaccination cost, $786,413) with a median conflict interval of 16 days. Among 704,591 children who received at least one live vaccine dose from 2016-17, 1,001 (0.1%) received at least one dose too soon after a prior live vaccine (revaccination cost, $181,565) with a median conflict interval of 14 days. The live vaccine most frequently administered outside of the recommended intervals was LAIV from 2014-15, and varicella from 2016-17.

CONCLUSIONS

Live vaccine interval errors were rare (0.5%), indicating an adherence to recommendations. If all invalid doses were corrected by revaccination over the two time periods, the cost within the IIS Sentinel Sites would be nearly one million dollars. Provider awareness about live vaccine conflicts, especially with LAIV, could prevent errors, and utilization of clinical decision support functionality within IISs and Electronic Health Record Systems can facilitate better vaccination practices.

Measles, mumps, rubella, and varicella among service members and other beneficiaries of the Military Health System, 1 January 2016-30 June 2019

Measles, mumps, rubella, and varicella (MMR/V) are highly communicable infectious diseases whose causative agents are spread through contact with contaminated surfaces or airborne droplets. Individuals at highest risk for MMR/V infections include infants; unvaccinated or inadequately vaccinated persons; individuals living in communities with low vaccination rates or in crowded, unsanitary conditions; and persons with compromised immune systems. Between 1 January 2016 and 30 June 2019, there were 5 confirmed measles cases and 64 confirmed mumps cases among all Military Health System (MHS) beneficiaries. During this period, no cases of measles were reported among U.S. service members. There were 29 confirmed mumps cases among service members during the surveillance period; 2 cases occurred in 2016, 17 in 2017, 5 in 2018, and 5 in the first 6 months of 2019. There were 6 confirmed rubella cases among all MHS beneficiaries. Among service members, there were 39 confirmed cases of varicella during the surveillance period; 9 cases occurred in 2016, 11 in 2017, 11 in 2018, and 8 in the first 6 months of 2019. Recent trends in MMR/V in both military and civilian populations in the U.S. highlight the importance of primary and booster vaccinations.

Burden of varicella in Latin America and the Caribbean: findings from a systematic literature review

BACKGROUND

Varicella is typically mild and self-limiting, but can be associated with complications and even death. The limited data available on varicella in Latin America and the Caribbean (LAC) indicate substantial burden in countries where varicella vaccine is not part of publicly funded childhood national immunization programs.

METHODS

A systematic literature review of published studies was complemented by "gray" literature on varicella incidence, complications, mortality, and economic consequences, in the absence and presence of universal varicella vaccination (UVV) in LAC.

RESULTS

Seroprevalence data indicate that varicella is usually a disease of childhood in LAC. Varicella incidence rates, while unreliable in the absence of mandatory reporting, show a trend to increased incidence due to greater urbanization and population density. The introduction of UVV in national immunization programs has led to significant reductions in varicella incidence in these areas.

CONCLUSIONS

Varicella continues to pose a substantial healthcare burden in LAC. The future introduction of UVV in additional countries is predicted to provide substantial reductions in cases, with important economic benefits. For countries that have already implemented UVV, the challenge is to maintain high rates of coverage and, where relevant, consider inclusion of a second dose to reduce breakthrough cases. Given the significant proportion of the region now implementing UVV, a regional recommendation in order to prevent any potential for age-shifts in varicella infection might be considered.

Vaccine Strain Varicella Infection in an Infant With Previously Undiagnosed Perinatal Human Immunodeficiency Type-1 Infection

A 15-month-old infant with a history of developmental delay and weight loss with multiple hospital admissions was diagnosed with a pustular lesion identified as vaccine strain varicella at the vaccination site. He was ultimately determined to be HIV infected following a protracted evaluation, which did not initially include HIV since his mother was confirmed HIV seronegative at 3 months gestation.

Effects of One-dose Varicella Vaccination on Disease Severity in Children during Outbreaks in Seoul, Korea

BACKGROUND

In Korea, the incidence of varicella has increased despite the introduction of a universal one-dose vaccination for children aged 12-15 months in 2005. A previous study demonstrated that the vaccine effectiveness was insufficient to prevent against varicella. We assessed the effect of the varicella vaccination on disease severity.

METHODS

Epidemiologic investigation of varicella cases in Seoul metropolitan area from 2015 to 2017 were used. Varicella-related symptoms such as rash were determined by the clinical practitioners. Disease severity of patients was assessed by the number of skin lesions and divided into mild (≤ 50) and moderate (51-249) to severe (≥ 250). Unconditional logistic regression analysis was performed and age was controlled.

RESULTS

Among a total of 1,008 varicella cases reported, 869 cases were breakthrough cases and 139 were unvaccinated cases. The risk for occurrence of moderate-to-severe disease in the breakthrough group was 0.57 times less than that of the unvaccinated group.

CONCLUSION

These data suggest that national varicella vaccination may have a significant effect on attenuation of disease severity in children.

Severe Herpes Zoster Following Varicella Vaccination in Immunocompetent Young Children

Varicella vaccination is now virtually universal in North America, as well as in some European and Asian countries. Since varicella vaccine is a live attenuated virus, the virus replicates in the skin after administration and can travel via sensory nerves or viremia to become latent in the dorsal root ganglia. In some immunized children, virus reactivates within a few months to a few years to cause the dermatomal exanthem known as herpes zoster (shingles). Herpes zoster caused by vaccine virus often reactivates within the same dermatome as the site of the original varicella vaccine injection. We present evidence that occasional cases of herpes zoster following varicella vaccination in immunocompetent children can be as severe as herpes zoster following wild-type varicella. Analysis of the virus in one case disclosed that the vaccine virus causing herpes zoster was a wild-type variant with a mutation in ORF0. With regard to dermatomal localization of the viral eruption, we predict that herpes zoster of the lumbar dermatomes in children is likely to be caused by vaccine virus, because herpes zoster in those dermatomes is rare in children after wild-type varicella. One of the children with herpes zoster subsequently developed asthma, a known risk factor for herpes zoster, but none of the children had an autoimmune disease. Although postherpetic neuralgia is exceedingly rare, children who develop herpes zoster following varicella vaccination are at risk (albeit low) of developing meningoencephalitis and should be carefully observed for a few weeks.

[Consensus for the management of infectious diseases among asylum seekers and detainees in the canton of Vaud]

Our work develops procedures and useful tools for the screening, assessment and management of prevalent infectious or parasitic diseases (tuberculosis, measles, chickenpox, scabies, bed bugs) among asylum seekers and detainees in the canton of Vaud, populations living in similar closed settings. Its aim is to support health professionals in their work, to maintain the health of the target population and to protect the health of the community. Through a literature review and a focus group with experts, it is proposed to harmonize the existing procedures in asylum seekers centres end prisons of the canton of Vaud. The proposed decision algorithms are coherent with the recommendations of the literature and relevant in terms of public health and ethics, as well as feasible logistically and acceptable by the field health professionals.

Epidemiological Impact of the Korean National Immunization Program on Varicella Incidence

The number of reported varicella cases is continuously increasing in Korea; however, associated medical utilization is declining. The ratio between varicella insurance claims and reports of passive infectious disease surveillance has gradually increased to > 80% since the second half of 2017. The recent increase in reported varicella cases is influenced by improved reporting. We calculated the varicella incidence and cumulative incidence in each birth cohort according to age. The cumulative incidence rate among children aged < 6 years in the birth cohort born after the National Immunization Program introduced the varicella vaccine was about 60% lower than among children born before.

Increasing varicella incidence rates among children in the Republic of Korea: an age-period-cohort analysis

In the Republic of Korea, despite the introduction of one-dose universal varicella vaccination in 2005 and achieving a high coverage rate of 98.9% in 2012, the incidence rate has been increased sevenfold. This study aimed to investigate time trends of varicella incidence rate, assessing the age, period and birth cohort effects. We used national data on the annual number of reported cases from 2006 to 2017. A log-linear Poisson regression model was used to estimate age-period-cohort effects on varicella incidence rate. From 2006 to 2017, the incidence of varicella increased from 22.5 cases to more than 154.8 cases per 100 000. Peak incidence has shifted from 4 to 6 years old. The estimated period and cohort effects showed significant upward patterns, with a linear increasing trend by net drift. There has been an increase in the incidence among the Korean population regarding period and cohort despite the universal vaccination of varicella vaccine. Our data suggest the need for additional studies to address the current gap in herd immunity.

Global impact of varicella vaccination programs

Although varicella is usually a mild and self-limited disease, complications can occur. In 1998, the World Health Organization recommended varicella vaccination for countries where the disease has a significant public health burden. Nonetheless, concerns about a shift in the disease to older groups, an increase in herpes zoster in the elderly and cost-effectiveness led many countries to postpone universal varicella vaccine introduction. In this review, we summarize the accumulating evidence, available mostly from high and middle-income countries supporting a high impact of universal vaccination in reductions of the incidence of the disease and hospitalizations and its cost-effectiveness. We have also observed the effect of herd immunity and noted that there is no definitive and consistent association between vaccination and the increase in herpes zoster incidence in the elderly.

Talk to Patients About: Varicella

The varicella-zoster virus does double-duty: It can cause chickenpox when you're young and reactivate later in life as a painful, blistery rash called shingles. Well, there's a vaccine for each disease.

Management of chickenpox in pregnant women: an Italian perspective

Chickenpox is a highly contagious disease caused by primary infection of varicella zoster virus (VZV). The disease is spread worldwide and is usually benign but, in some groups of population like pregnant women, can have a severe outcome. Due to a not optimal vaccination coverage, a relatively high number of childbearing-aged women in a European country such as Italy tested seronegative for VZV and so are currently at risk of acquiring chickenpox during pregnancy, especially if they live in contact with children for family or work reasons. Only few data are available about the risk of infection in this setting: the incidence of chickenpox may range from 1.5 to 4.6 cases/1000 childbearing females and from 1.21 to 6 cases/10,000 pregnant women, respectively. This review is aimed to focus on the epidemiology and the clinical management of exposure to chickenpox during pregnancy. Particular emphasis is given to the accurate screening of childbearing women at the time of the first gynecological approach - the females who tested susceptible to infection can be counseled about the risks and instructed on procedure should contact occur - and to the early prophylaxis of the at-risk exposure. Lastly, the achievement of adequate vaccination coverage of the Italian population remains a cornerstone in the prevention of chickenpox in pregnancy.

Descriptive epidemiology of varicella based on national surveillance data before and after the introduction of routine varicella vaccination with two doses in Japan, 2000-2017

Routine childhood immunization using two doses of the varicella vaccine was introduced in Japan in October 2014. In this study, we analyzed the data extracted from national varicella surveillance, including pediatric sentinel surveillance from 2000 to 2017 and hospitalized varicella surveillance from the 38th week of 2014 to the 37th week of 2017. Compared with the 2000-2011 baseline data, the number of varicella cases per sentinel decreased substantially by 76.6% overall and by 88.2% among children aged 1-4 years in 2017. Of 997 hospitalized patients, we found a decreasing trend in the number of cases among children aged <5 years. We also found a decreasing trend in the number of cases with complications among children aged 1-4 years. Data on the self-reported transmission sites in 35.5% (354/997) of the hospitalized varicella patients showed that transmission of varicella zoster virus (VZV) occurred frequently in household, at school for young children, in the workplace for adults, and at hospital for all age groups. Data from 29.0% (289/997) of the hospitalized patients with a self-reported source of infection showed that transmission of VZV occurred from a patient with herpes zoster (HZ) in 30.4% (88/289) of cases. Our data demonstrate a substantial decrease in the number of varicella cases in young children following introduction of routine childhood vaccination program with two-dose varicella vaccination in Japan. These data highlight the unique aspects of transmission sites across age groups and the important role of HZ cases in disease circulation.