Effect of climatic factors and population density on varicella zoster virus epidemiology within a tropical country

Differential diagnosis of exanthematous viruses during the 2022 Mpox outbreak in Minas Gerais, Brazil

The monkeypox virus (MPXV) outbreak, primarily endemic to Africa, has spread globally, with Brazil reporting the second-highest number of cases. The emergence of MPXV in non-endemic areas has raised concerns, particularly due to the co-circulation of other exanthematous viruses such as varicella-zoster virus (VZV) and molluscum contagiosum virus (MOCV). To perform an accurate differential diagnosis of MPXV during the ongoing outbreak in Minas Gerais, Brazil, a 5PLEX qPCR assay targeting orthopoxviruses (OPV), VZV, and MOCV was used to retrospectively analyze all clinical samples that tested negative for MPXV in the initial screening conducted at Funed. In summary, our study analyzed 1,175 clinical samples received from patients suspected of MPXV infection and found a positivity rate of 33.8% (397 samples) for MPXV using the non-variola qPCR assay. Testing the 778 MPXV-negative clinical samples using the 5PLEX qPCR assay revealed that 174 clinical samples (22.36%) tested positive for VZV. MOCV DNA was detected in 13 and other OPV in 3 clinical samples. The sequencing of randomly selected amplified clinical samples confirmed the initial molecular diagnosis. Analysis of patient profiles revealed a significant difference in the median age between groups testing positive for MPXV and VZV and a male predominance in MPXV cases. The geographic distribution of positive cases was concentrated in the most populous mesoregions of Minas Gerais state. This study highlights the challenges posed by emerging infectious diseases. It emphasizes the importance of epidemiological surveillance and accurate diagnosis in enabling timely responses for public health policies and appropriate medical care.

IMPORTANCE

Brazil ranks second in the number of cases during the global monkeypox epidemic. The study, conducted in Minas Gerais, the second most populous state in Brazil with over 20 million inhabitants, utilized differential diagnostics, revealing a significant number of positive cases for other exanthematous viruses and emphasizing the need for accurate diagnoses. During the study, we were able to assess the co-circulation of other viruses alongside monkeypox, including varicella-zoster virus, molluscum contagiosum virus, and other orthopoxviruses. The significance of the research is underscored by the concentration of positive cases in populous areas, highlighting the challenges posed by emerging infectious diseases. This demographic context further amplifies the importance of the research in guiding public health policies and medical interventions, given the substantial population at risk. The study not only addresses a global concern but also holds critical implications for a state with such a large population and geographic expanse within Brazil. Overall, the study emphasizes the pivotal role of surveillance and precise diagnosis in guiding effective public health responses and ensuring appropriate medical interventions.

Characteristics and economic burden of hospitalized patients with herpes zoster in China, before vaccination

Herpes zoster (HZ) brings a significant economic burden. The HZ vaccine was introduced in China for the first time in 2020, and there is a lack of up-to-date information on the hospitalization costs and characteristics prior to vaccination. This study aimed to describe the characteristics and economic burden of HZ inpatients in Hunan Province, China, and analyze the factors influencing the length of stay (LOS) and costs. This was a retrospective study and we extracted information from the Chinese National Health Statistics Network Reporting System on HZ inpatients in Hunan Province, China from 2017 to 2019. Spatial join tools and Global or Local Moran's Index were used for the geographic analysis of hospitalized HZ incidence. Multivariate linear regression models were used to analyze the factors influencing LOS and costs. There were 44,311 HZ inpatients included in this study, incurring a total of $31,857,734 medical costs. These patients had a median LOS of 8 days and a median expenditure of $573.47. Older age, more comorbidities, and the presence of complications with nervous system involved were all significantly associated with longer LOS and higher costs. HZ infection resulted in a large direct medical cost and heavy disease burden, especially in patients with advanced age or underlying medical conditions. The HZ vaccine has the potential to effectively reduce the disease burden and should be widely popularized especially among high-risk groups.

Current Perspectives on the Management of Herpesvirus Infections in Solid Organ Transplant Recipients

Solid organ transplant recipients (SOTRs) are at high risk of human herpesvirus (HHV)-related morbidity and mortality due to the use of immunosuppressive therapy. We aim to increase awareness and understanding of HHV disease burden in SOTRs by providing an overview of current prevention and management strategies as described in the literature and guidelines. We discuss challenges in both prevention and treatment as well as future perspectives.

Systematic Literature Review of Herpes Zoster Disease Burden in Southeast Asia

INTRODUCTION

Herpes zoster (HZ; i.e., shingles) is caused by the reactivation of varicella zoster virus leading to a painful dermatomal rash. An increasing trend in cases of HZ is evident worldwide; however, there is a lack of comprehensive reviews for Southeast Asian countries.

METHODS

We performed a systematic literature review of articles published until May 2022 that reported HZ epidemiology, clinical management, and health economic data in six Southeast Asian countries: Indonesia, Malaysia, the Philippines, Singapore, Thailand, and Vietnam. Literature searches were conducted in Medline, Scopus, Embase, and gray literature. Articles written in English or local languages were considered for inclusion.

RESULTS

In total, 72 publications were included in the study; 22 were case studies and over 60% originated in Singapore and Thailand. Only two studies (data from Thailand) reported incidence of HZ. The proportion of patients reported with HZ was 0.68-0.7% among dermatology clinics, 0.14% at one emergency department (5.3% of dermatology cases) in Singapore, and 3% of admissions at another hospital in Singapore. Pain was the most common symptom associated with HZ, reported in 74.21-100% of patients. HZ complications were reported in 10.2-21.2% of patients, and the proportions with postherpetic neuralgia and HZ ophthalmicus were 6.3-50% and 4.98-28.57%, respectively. Additionally, there is a lack of comprehensive, up-to-date HZ economic data, with only six studies identified for the Philippines, Singapore, and Thailand.

CONCLUSIONS

Overall, there are limited data reporting incidence and prevalence of HZ in Southeast Asia at a national level. High rates of complications, symptoms, and abundance of case reports suggest substantial healthcare resource utilization for patients with HZ and highlight the need for further research in Southeast Asia assessing the societal impact.

Antimicrobial use for the management of varicella in Thailand: a retrospective observational study

OBJECTIVE

To describe the clinical characteristics of varicella patients seeking medical consultation and the use of antimicrobials for their management in Thailand in the absence of universal varicella vaccination (UVV).

METHODS

A multicenter, retrospective chart review of 260 children and adults with a primary diagnosis of varicella was conducted at one private and three public hospitals in Bangkok, Thailand. Charts of varicella patients (inpatient or outpatient) were randomly selected over a 5-year period. Key outcomes included clinical complications and the use of antibiotics, antivirals, and other medications.

RESULTS

Charts of 200 children (mean age 5.7 years, range 0.3-16 years) and 60 adults (mean age 27.9 years, range 18-50 years) were reviewed. Fourteen patients (including 8 children) were hospitalized. Five percent of the children and none of the adults were immunocompromised. At least 1 varicella-related complication was reported by 7.3% (7% of children, 8.3% of adults, p = .778) of all patients, including 57.1% (62.5% of children, 50% of adults) of inpatients (p < .001, compared with outpatients). Skin/soft tissue infection (47.7%) and dehydration (47.4%) were the most common complications. Antivirals (mainly oral acyclovir) were prescribed to 46.5% of patients (31.5% of children, 96.7% of adults, p < .001). Antibiotics were prescribed to 20.8% of patients (19% of children, 26.7% of adults, p = .199). Topical, oral, and intravenous antibiotics were prescribed to 12.3%, 8.5%, and 1.2% of patients, respectively. Antimicrobial prescriptions were higher among adults (p < .001) and immunocompromised patients (p = .025). Apart from antimicrobials, acetaminophen (62.3%) and oral antihistamines (51.5%) were the most prescribed.

CONCLUSION

A considerable number of varicella patients, both children and adults, seeking medical consultation in Thai hospitals are prescribed antibiotics and antivirals, with one-fifth of patients being prescribed an antibiotic and almost half prescribed an antiviral. The study may be of interest to policymakers in Thailand and other Asia-Pacific countries considering UVV implementation.

Cross sectional survey of Varicella-Zoster virus and measles seropositivity in people living with HIV in a Parisian suburb and a review of current immunization guidelines

According to evidence-based guidelines, vaccines against measles and varicella are generally recommended to susceptible HIV-positive patients, as long as they are not severely immunocompromised. However, routine screening to determine serologic status is not recommended. We conducted a seroprevalence study of anti-measles and anti-Varicella-Zoster virus (VZV) antibodies in adults living with HIV (PLWHA) consulting at Avicenne University Hospital in a Parisian suburb. Sera were collected in years 2018-2020 and tested by commercial immunoassays in 268 patients. Most of the patients were born in Sub-Saharan Africa (55 %) and only 23 % in Europe. Measles and varicella seropositivity were present respectively in 91.4 % and 96.2 % of patients. One patient in ten was seronegative to at least one of tested diseases. In the univariate analysis, only younger age (p = 0.027) was associated with a higher risk of measles seronegativity, while shorter time since arrival in France (p < 0.001) and shorter time since HIV discovery (p = 0.007) were associated with a higher risk of VZV seronegativity. In multivariate analysis no association was found. This study highlights the absence of specific risk factors for VZV and measles seronegativity in PLWHA and supports the importance of routine screening, in order to increase immunization rates and reduce risk of complications.

Investigation of susceptibility genes for chickenpox disease across multiple continents

Chickenpox (varicella) is caused by infection with the varicella-zoster virus (VZV), a neurotropic alpha herpes virus with a double-stranded DNA genome. Chickenpox can cause life-threatening complications, including subsequent bacterial infections, central nervous system symptoms, and even death without any risk factors. Few studies have been reported to investigate genetic susceptibility implicated in chickenpox. Herein, our study identified global genetic variants that potentially contributed to chickenpox susceptibility by utilizing the established bioinformatic-based approach. We integrated several databases, such as genome-wide association studies (GWAS) catalog, GTEx portal, HaploReg version 4.1, and Ensembl databases analyses to investigate susceptibility genes associated with chickenpox. Notably, increased expression of HLA-S, HCG4P5, and ABHD16A genes underlie enhanced chickenpox susceptibility in the European, American, and African populations. As compared to the Asian population, Europeans, Americans, and Africans have higher allele frequencies of the extant variants rs9266089, rs10947050, and rs79501286 from the susceptibility genes. Our study suggested that these susceptibility genes and associated genetic variants might play a critical role in chickenpox progression based on host genetics with clinical implications.

Lower infant mortality, higher household size, and more access to contraception reduce fertility in low- and middle-income nations

Although average contraceptive use has increased globally in recent decades, an estimated 222 million (26%) of women of child-bearing age worldwide face an unmet need for family planning-defined as a discrepancy between fertility preferences and contraception practice, or failing to translate desires to avoid pregnancy into preventative behaviours and practices. While many studies have reported relationships between availability/quality of contraception and family planning, infant mortality, and fertility, these relationships have not been evaluated quantitatively across a broad range of low- and middle-income countries. Using publicly available data from 64 low- and middle-income countries, we collated test and control variables in six themes: (i) availability of family planning, (ii) quality of family planning, (iii) female education, (iv) religion, (v) mortality, and (vi) socio-economic conditions. We predicted that higher nation-level availability/quality of family-planning services and female education reduce average fertility, whereas higher infant mortality, greater household size (a proxy for population density), and religious adherence increase it. Given the sample size, we first constructed general linear models to test for relationships between fertility and the variables from each theme, from which we retained those with the highest explanatory power within a final general linear model set to determine the partial correlation of dominant test variables. We also applied boosted regression trees, generalised least-squares models, and generalised linear mixed-effects models to account for non-linearity and spatial autocorrelation. On average among all countries, we found the strongest associations between fertility and infant mortality, household size, and access to any form of contraception. Higher infant mortality and household size increased fertility, whereas greater access to any form of contraception decreased fertility. Female education, home visitations by health workers, quality of family planning, and religious adherence all had weak, if any, explanatory power. Our models suggest that decreasing infant mortality, ensuring sufficient housing to reduce household size, and increasing access to contraception will have the greatest effect on decreasing global fertility. We thus provide new evidence that progressing the United Nation's Sustainable Development Goals for reducing infant mortality can be accelerated by increasing access to family planning.

Reassessment of Evidence about Coinfection of Chickenpox and Monkeypox (Mpox) in African Children

In west and central Africa, monkeypox occurs mainly in older children, adolescents and young adults. In two large epidemiology studies of monkeypox outbreaks, the investigators observed a sizable number of coinfections of chickenpox (varicella) and monkeypox. Based on a review of the literature, we propose that chickenpox (human herpesvirus-3 infection) is a risk factor for acquisition of monkeypox infection. Our hypothesis states that the chickenpox skin lesion provides an entry site for the monkeypox virus, which is harbored on a fomite in the environment of the patient. The fact that monkeypox can enter via a scratch or abrasion is a known mechanism of spread for three other poxviruses, including mousepox (ectromelia), orf and molluscum contagiosum. There are many similarities in pathogenesis between certain poxviruses and chickenpox, including a viremia with a cellular stress response leading to high levels of the IL-6 cytokine. One very revealing observation in the two epidemiology studies was that the number of pox as well as the severity of disease in children with chickenpox and monkeypox coinfection was not greater than found in children with monkeypox alone. Based on the above observations, we conclude that, when chickenpox precedes monkeypox, priming of the immune system by the earlier chickenpox infection moderates the severity of the secondary infection with monkeypox. This conclusion also has important public health implications about chickenpox surveillance.

Association between ambient temperature and varicella among adults in Qingdao, China during 2008-2019

Little concern has been paid to the relationship between temperature and varicella among adults. Daily meteorological data and varicella cases in Qingdao among adults from 1 January 2008 to 31 December 2019 were collected. A combination of quasi-Poisson generalized additive model (GAM) and distributed lag non-linear model (DLNM) was conducted to assess the temperature-lag-varicella relationship. We also estimated the lag-response curves for different temperatures and the exposure-response relationships for different lag days. The number of varicella cases was 10,296. Compared with the minimum-varicella temperature (25°C), we found the largest effect of temperature on varicella within 21 lag days was at 1°C (RR, 6.72; 95% CI, 2.90-15.57), and then the effect declined as the temperature increased. A similar trend of rising first and then falling was found in temperature-response curves for different lag days. A reverse U-shape lag pattern was found for different levels of temperatures. Temperature may affect varicella.

Influence of climate variables on dengue fever occurrence in the southern region of Thailand

The 3-5year epidemic cycle of dengue fever in Thailand makes it a major re-emerging public health problem resulting in being a burden in endemic areas. Although the Thai Ministry of Public Health adopted the WHO dengue control strategy, all dengue virus serotypes continue to circulate. Health officers and village health volunteers implement some intervention options but there is a need to ascertain most appropriate (or a combination of) interventions regarding the environment and contextual factors that may undermine the effectiveness of such interventions. This study aims to understand the dengue-climate relationship patterns at the district level in the southern region of Thailand from 2002 to 2018 by examining the statistical association between dengue incidence rate and eight environmental patterns, testing the hypothesis of equal incidence of these. Data on environmental variables and dengue reported cases in Nakhon Si Thammarat province situated in the south of Thailand from 2002 to 2018 were analysed to (1) detect the environmental factors that affect the risk of dengue infectious disease; to (2) determine if disease risk is increasing or decreasing over time; and to (3) identify the high-risk district areas for dengue cases that need to be targeted for interventions. To identify the predictors that have a high and significant impact on reported dengue infection, three steps of analysis were used. First, we used Partial Least Squares (PLS) Regression and Poisson Regression, a variant of the Generalized Linear Model (GLM). Negative co-efficient in correspondence with the PLS components suggests that sea-level pressure, wind speed, and pan evaporation are associated with dengue occurrence rate, while other variables were positively associated. Using the Akaike information criterion in the stepwise GLM, the filtered predictors were temperature, precipitation, cloudiness, and sea level pressure with the standardized coefficients showing that the most influential variable is cloud cover (three times more than temperature and precipitation). Also, dengue occurrence showed a constant negative response to the average increase in sea-level pressure values. In southern Thailand, the predictors that have been locally determined to drive dengue occurrence are temperature, rainfall, cloud cover, and sea-level pressure. These explanatory variables should have important future implications for epidemiological studies of mosquito-borne diseases, particularly at the district level. Predictive indicators guide effective and dynamic risk assessments, targeting pre-emptive interventions.

Pattern of Skin Diseases in Geriatric Population: Our Year-Long Experience from Nepal

Introduction:

The average life span has increased by about two decades in Nepal in last 30 years. With increasing longevity, geriatric health care is gaining much more importance. The statistical data regarding the geriatric skin disorders in Nepalese population is limited. The aim of this study to look for the patterns of skin diseases in the geriatric population of Nepal.

Methodology:

This is a retrospective, descriptive study where we reviewed the database of patients visiting the dermatology outpatient department of multispeciality teaching hospital in Nepal from August 2016 to July 2017. All patients from the age of 60 and above were included in the study. Data was analyzed using SPSS version 20. Chi square test was done where relevant.

Result:

Total of 918 patients were included in the study with mean age of 69 years. Most common presentation was that of dermatitis (32.2%) which was followed by infectious condition (29.4%), pruritus (7.4%), psoriasis (4.6%), urticaria (3.9%), miliaria (3.9%) and others. Among the dermatitis, 23% of the patients had hand or feet eczema and 23% had sebohrreic dermatitis. Variability according to weather was noticed with in presentation of sebohrreic dermatitis, dermatophytic infections, miliaria and herpes zoster.

Conclusion:

This study concludes that dermatitis, infections and pruritus are the most significant dermatological morbidities in our population. It highlights the need of zoster vaccine for our elderly population as it is not a part of the routine vaccination scheme in Nepal.

Migration and outbreaks of vaccine-preventable disease in Europe: a systematic review

Migrant populations are one of several underimmunised groups in the EU or European Economic Area (EU/EEA), yet little is known about their involvement in outbreaks of vaccine-preventable diseases. This information is vital to develop targeted strategies to improve the health of diverse migrant communities. We did a systematic review (PROSPERO CRD42019157473; Jan 1, 2000, to May 22, 2020) adhering to PRISMA guidelines, to identify studies on vaccine-preventable disease outbreaks (measles, mumps, rubella, diphtheria, pertussis, polio, hepatitis A, varicella, Neisseria meningitidis, and Haemophilus influenzae) involving migrants residing in the EU/EEA and Switzerland. We identified 45 studies, reporting on 47 distinct vaccine-preventable disease outbreaks across 13 countries. Most reported outbreaks involving migrants were of measles (n=24; 6496 cases), followed by varicella (n=11; 505 cases), hepatitis A (n=7; 1356 cases), rubella (n=3; 487 cases), and mumps (n=2; 293 cases). 19 (40%) outbreaks, predominantly varicella and measles, were reported in temporary refugee camps or shelters. Of 11 varicella outbreaks, nine (82%) were associated with adult migrants. Half of measles outbreaks (n=11) were associated with migrants from eastern European countries. In conclusion, migrants are involved in vaccine-preventable disease outbreaks in Europe, with adult and child refugees residing in shelters or temporary camps at particular risk, alongside specific nationality groups. Vulnerability varies by disease, setting, and demographics, highlighting the importance of tailoring catch-up vaccination interventions to specific groups in order to meet regional and global vaccination targets as recommended by the new Immunisation Agenda 2030 framework for action. A better understanding of vaccine access and intent in migrant groups and a greater focus on co-designing interventions is urgently needed, with direct implications for COVID-19 vaccine delivery.

Seroprevalence of ToRCH Pathogens in Southeast Asia

ToRCH is the acronym for several pathogens associated with pregnancy complications and sequelae in the unborn or newborn child. Particularly primary infections during pregnancy are associated with increased risk. Seroprevalence data of ToRCH infections are important, especially in countries with weak disease surveillance systems, to estimate immunity and vaccination levels, as well as exposure rates and thus the risk of infection during pregnancy. A systematic literature search spanning a 30-year time period was conducted to identify serosurveys on ToRCH pathogens in Southeast Asia. The 96 identified studies showed that some pathogens were well studied, while only limited data were available for others. Studies from the better-developed countries of the region were more abundant. Moreover, seroprevalence data were often limited to a certain geographical region within the country or to certain cohorts, there was an evident lack of recent serosurveys, and the study quality was often not adequate. Well-designed and area-wide serosurveys of ToRCH pathogens are clearly warranted. If combined with risk factor analysis, these studies may guide the development and implementation of effective measures for infection prevention, especially during pregnancy. In addition, educational programs for health care workers and for pregnant women during antenatal care are urgently needed.

Varicella in Adult Foreigners at a Referral Hospital, Central Tokyo, Japan, 2012-2016

We report a case series of varicella among adult foreigners at a referral hospital in central Tokyo, Japan, during 2012–2016. This series highlights differences in varicella vaccination schedules by country and epidemiology by climate and identifies immigrants and international students as high-risk populations for varicella.

Effect of meteorological factors on COVID-19 cases in Bangladesh

This work is intended to examine the effects of Bangladesh's subtropical climate on coronavirus diseases 2019 (COVID-19) transmission. Secondary data for daily meteorological variables and COVID-19 cases from March 8 to May 31, 2020, were collected from the Bangladesh Meteorological Department (BMD) and Institute of Epidemiology, Disease Control and Research (IEDCR). Distributed lag nonlinear models, Pearson's correlation coefficient and wavelet transform coherence were employed to appraise the relationship between meteorological factors and COVID-19 cases. Significant coherence between meteorological variables and COVID-19 at various time-frequency bands has been identified in this work. The results showed that the minimum (MinT) and mean temperature, wind speed (WS), relative humidity (RH) and absolute humidity (AH) had a significant positive correlation while contact transmission had no direct association with the number of COVID-19 confirmed cases. When the MinT was 18 °C, the relative risk (RR) was the highest as 1.04 (95%CI 1.01-1.06) at lag day 11. For the WS, the highest RR was 1.03 (95% CI 1.00-1.07) at lag day 0, when the WS was 21 km/h. When RH was 46%, the highest RR was 1.00 (95% CI 0.98-1.01) at lag day 14. When AH was 23 g/m³, the highest RR was 1.05 (95% CI 1.01-1.09) at lag day 14. We found a profound effect of meteorological factors on SARS-CoV-2 transmission. These results will assist policymakers to know the behavioral pattern of the SARS-CoV-2 virus against meteorological indicators and thus assist to devise an effective policy to fight against COVID-19 in Bangladesh.

Dengue Seroprevalence and Seroconversion in Urban and Rural Populations in Northeastern Thailand and Southern Laos

Dengue is the most rapidly spreading mosquito-borne viral disease in the world. The detection of clinical cases enables us to measure the incidence of dengue infection, whereas serological surveys give insights into the prevalence of infection. This study aimed to determine dengue seroprevalence and seroconversion rates in northeastern Thailand and southern Laos and to assess any association of mosquito control methods and socioeconomic factors with dengue virus (DENV) infection. Cross-sectional seroprevalence surveys were performed in May and November 2019 on the same individuals. Blood samples were collected from one adult and one child, when possible, in each of 720 randomly selected households from two urban and two rural sites in both northeastern Thailand and southern Laos. IgG antibodies against DENV were detected in serum using a commercial enzyme-linked immunosorbent assay (ELISA) kit. Overall, 1071 individuals participated in the study. The seroprevalence rate was high (91.5%) across all 8 study sites. Only age and province were associated with seroprevalence rates. There were 33 seroconversions during the period from May to November, of which seven reported fever. More than half of the seroconversions occurred in the rural areas and in Laos. Dengue seroconversion was significantly associated with young age (<15 years old), female gender, province, and duration of living in the current residence. No socioeconomic factors or mosquito control methods were found to be associated with seroprevalence or seroconversion. Notably, however, the province with most seroconversions had lower diurnal temperature ranges than elsewhere. In conclusion, our study has highlighted the homogeneity of dengue exposure across a wide range of settings and most notably those from rural and urban areas. Dengue can no longer be considered to be solely an urban disease nor necessarily one linked to poverty.

Prevalence of herpes -, measles morbillivirus-, parvovirus B19 - and rubella viruses immunoglobulin G among women with chronic hepatitis B of reproductive age in Denmark: A cross-sectional study

OBJECTIVES

The aim of this study was to investigate whether the seroprevalence of IgG antibodies against seven viruses (cytomegalovirus, herpes simplex virus 1&2, measles morbillivirus, parvovirus B19, rubella, and varicella-zoster virus), which can potentially compromise maternal and fetal wellbeing, differs based on country of origin among women with chronic hepatitis B (CHB).

METHOD

This study was a single-center, hospital-based cross-sectional study. The study included women with CHB 15-45 years of age, included in the Danish Database for Hepatitis B and C. Seroprevalence estimates were calculated with a 95% confidence interval and were compared between age groups, regions of origin, and to the general population.

RESULTS

177 women were included in the study. Overall, the seroprevalences of antibodies were similar among women with CHB with origin outside Denmark and compared to the general population in Denmark, but there was a notable difference in the seroprevalence of antibodies against herpes simplex 2 between women from Africa (37.1% CI 95% 22.0;55.1) and women from the Middle East (2.5% CI 95% 0.1;14.7).

CONCLUSION

Women with CHB whose origin is outside Denmark do not appear to differ, based on origin, or be at greater risk of acquiring these viruses during pregnancy than their Danish counterparts.

Association between climatic factors and varicella incidence in Guangzhou, Southern China, 2006-2018

OBJECTIVE

To analyze the correlation between climatic factors and the incidence of varicella in Guangzhou, and improve the prevention measures about public health.

METHODS

Data for daily climatic variables and varicella incidence from 2006 to 2018 in Guangzhou were collected from the Guangzhou Meteorological Bureau and the National Notifiable Disease Report System. Distributed lag nonlinear models were applied to evaluate the association between climatic factors and varicella incidence.

RESULTS

The nonlinear effects of meteorological factors were observed. At lag day21，when the mean temperature was 31.8 °C, the relative risk was the highest as 1.11 (95% CI: 1.07-1.16). When the diurnal temperature range was 24.0 °C at lag day 20, the highest RR was 1.11 (95% CI: 1.05-1.17). For rainfall, the highest RR was 1.09 (95% CI: 1.01-1.19) at lag day 21，when the aggregate rainfall was 160 mm. When air pressure was 1028 hPa, the highest RR was 1.08 (95% CI: 1.04-1.13) at lag day 21. When wind speed was 0.7 m/s, the highest RR was 1.07 (95% CI: 1.04-1.11) at lag day 7. When the hours of sunshine were 9.0 h at lag day 21, the RR was highest as 1.04 (95% CI: 1.02-1.05). Aggregate rainfall, air pressure, and sunshine hours were positively correlated with the incidence of varicella, which was inconsistent with the wind velocity. Mean temperature showed a reverse U-shape curve relationship with varicella, while the diurnal temperature range showed a binomial distribution curve. The extreme effect of climatic factors on the varicella cases was statistically significant, apart from the extremely low effect of rainfall.

CONCLUSION

Our preliminary results offered fundamental knowledge which might be benefit to give an insight into epidemic trends of varicella and develop an early warning system. We could use our findings about influential factors to strengthen the intervention and prevention of varicella.

Epidemiology of varicella among immigrants and non-immigrants in Quebec, Canada, before and after the introduction of childhood varicella vaccination: a retrospective cohort study

BACKGROUND

Many immigrants are susceptible to varicella on arrival to Canada because of different transmission dynamics in their countries of origin and scarcity of vaccination. Universal childhood vaccination programmes decrease varicella incidence rates through herd immunity, but the accumulating number of susceptible adult immigrants could remain at risk for severe varicella. Our aim was to describe the epidemiology of varicella among immigrants and non-immigrants before and after childhood varicella vaccination.

METHODS

We did a population-based, retrospective cohort study of all varicella cases in Quebec, Canada, diagnosed between 1996 and 2014 in administrative health databases linked to immigration data. Cases of varicella met diagnostic codes in the International Classification of Diseases, Ninth and Tenth Revision Canadian modifications. Cases with a co-occurring zoster diagnostic code and immigrants from Australia, New Zealand, the USA, and western European countries were excluded. Vaccination periods included pre-vaccination (1996-98), private vaccination (1999-2005), and public vaccination (2006-14). Incidence rate and comparative rate ratios were estimated using census data.

FINDINGS

A total of 231 339 varicella cases diagnosed between Jan 1, 1996, and Dec 31, 2014, were linked to 1 115 696 immigrants who arrived between Jan 1, 1980, and Dec 31, 2014. 1444 herpes zoster cases and 1276 immigrants from Australia, western Europe, New Zealand, and the USA were excluded. Among 228 619 varicella cases, 13 315 (5·8%) occurred in immigrants. In pre-vaccination versus public vaccination periods, varicella incidence declined in immigrants by 87% (95% CI 86·6-87·9; 324·3 cases per 100 000 person-years to 40·9 cases per 100 000 person-years) and in non-immigrants by 93% (92·4-92·7; 484 cases per 100 000 person-years to 36 cases per 100 000 person-years). Mean age at diagnosis increased in both groups (15·1 vs 19·4 years in immigrants and 8·4 vs 12·0 years in non-immigrants). In the public vaccination period, immigrants younger than 50 years had higher varicella rates than non-immigrants, with relative risk ranging from 1·53 (95% CI 1·37-1·72) to 4·64 (3·90-5·53) with the highest risk in adolescents and young adults, and people from Latin America and the Caribbean (age-specific incidence rate ratio [aIRR]_I-NI pre-vaccination 2·19 and post-vaccination aIRR_I-NI6·07) and south Asia (aIRR_I-NI pre-vaccination 3·41 and aIRR_I-NI post-vaccination 4·46) and in childbearing women (15-40 years; IRR_I-NI 2·48).

INTERPRETATION

Immigrant adolescents, young adults, and women of childbearing age had higher age-standardised rates of varicella than non-immigrants, with increasing disparities following vaccine introduction. Immigrants younger than 50 years of age would benefit from targeted vaccination upon arrival to host countries.

FUNDING

The Canadian Institutes of Health Research and The Department of Medicine, Jewish General Hospital, Montreal, QC, Canada.

High varicella zoster virus susceptibility in Caribbean island populations: Implications for vaccination

OBJECTIVES

Varicella zoster virus (VZV) infection is reported regularly among adolescents and adults in Caribbean island populations. The disease more often runs a severe course among these populations, causing a substantial burden. The aim of this sero-epidemiological study was to obtain an insight into VZV susceptibility and its determinants in island populations of the Caribbean Netherlands (CN).

METHODS

Participants from Bonaire, St. Eustatius, and Saba (n = 1829, aged 0-90 years) donated a blood sample and completed a questionnaire. VZV-specific IgG antibodies were determined using a bead-based multiplex immunoassay. Risk factors were analysed using a logistic regression model.

RESULTS

Overall seroprevalence in CN was 78%, being lowest on St. Eustatius (73%) and highest on Bonaire and Saba (79%). Seropositivity increased gradually with age, with 60% and 80% at ages 10 years and 30 years, respectively, and ranging between 80% and 90% thereafter. Higher odds for VZV seronegativity were seen among persons who were born in CN or had resided there since early childhood, and among single-person households.

CONCLUSIONS

VZV susceptibility is relatively high among adolescents and adults in CN. In order to reduce the burden of VZV-related disease in these populations, routine varicella vaccination is recommended. As data are scarce, the study findings can serve as a blueprint for the epidemiology in tropical regions.

Characterization and Comparison of Genetic Variation in Clinical Varicella-Zoster Virus Isolates Collected from Shanghai and Urumqi, China

Varicella-zoster virus (VZV) is a ubiquitous human herpesvirus that causes chickenpox and zoster. Considering that VZV is a relatively and genetically stable virus, its global surveillance clades provide essential information for VZV evolution, immigration, and importation of different viral strains and recombination events. Eighty-eight VZV isolates from China (Shanghai and Urumqi) were genotyped using a scattered single-nucleotide polymorphism method in this prospective study. Our results were based on sequencing the open reading frames 1, 6, 12, 16, 17, 21, 22, 35, 37, 38, 50, 54, 55, 56, 60, and 66. We found that the majority of these 88 strains (81.8%) belonged to Clade 2 with significantly high homogeneity from Shanghai. However, in the Urumqi area, some strains were grouped to Clade 5, and some could not be attributed to any of the established VZV clades, although the majority of Urumqi strains belonged to Clade 2. Our results illustrated that due to geographical location, VZV could undergo genetic recombination, suggesting that VZV diversity is more complicated in certain areas and geographical separation contributes to VZV complexity.

Spatiotemporal Epidemiology of Varicella in Chongqing, China, 2014-2018

Although immunization against varicella using vaccines has been proven to be significant and effective in the past decades, varicella remains a major public health concern for many developing countries. Varicella vaccination has not been introduced into routine immunization programs in China, and varicella outbreaks have continued to occur. Taking the city of Chongqing, which has a high prevalence of varicella, as an example, this study explored the spatiotemporal epidemiology of varicella. Based on the reported data of varicella cases from 1 January 2014 to 31 December 2018 in Chongqing, hot spots and space-time clusters of varicella were identified using spatial autocorrelation analysis and scan statistics. Within this period, a total of 112,273 varicella cases were reported in Chongqing (average annual incidence: 73.44 per 100,000), including one death. The incidence of varicella showed an increasing trend with significant seasonal peaks, which occurred during April to July and October to January of the following year. The total ratio of male to female patients affected was 1.10:1. Children under the age of 15 and students accounted for the majority of the patient population. The hotspots detected through local spatial autocorrelation analysis, and the most likely clusters identified by scan analysis, were primarily in the main urban districts of Chongqing. The secondary clusters were mostly detected in northeast and southwest Chongqing. There were obvious spatial dependence and spatiotemporal clustering characteristics of varicella in Chongqing from 2014 to 2018. High-risk districts, populations, and peak periods were found in this study, which could be helpful in implementing varicella prevention and control programs, and in adjusting vaccination strategies for the varicella vaccine based on actual conditions.

Testing the socioeconomic and environmental determinants of better child-health outcomes in Africa: a cross-sectional study among nations

OBJECTIVE

We sought to test hypotheses regarding the principal correlates of child-health performance among African nations based on previous evidence collected at finer spatial scales.

DESIGN

Retrospective, cross-sectional study.

SETTING

All countries in Africa, excluding small-island nations.

PRIMARY AND SECONDARY OUTCOME MEASURES

We defined a composite child-health indicator for each country comprising the incidence of stunting, deaths from respiratory disease, deaths from diarrhoeal disease, deaths from other infectious disease and deaths from injuries for children aged under 5 years. We also compiled national-level data for Africa to test the effects of country-level water quality, air pollution, food supply, breast feeding, environmental performance, per capita wealth, healthcare investment, population density and governance quality on the child-health indicator.

RESULTS

Across nations, child health was lowest when water quality, improved sanitation, air quality and environmental performance were lowest. There was also an important decline in child health as household size (a proxy for population density) increased. The remaining variables had only weak effects, but in the directions we hypothesised.

CONCLUSIONS

These results emphasise the importance of continued investment in clean water and sanitation services, measures to improve air quality and efforts to restrict further environmental degradation, to promote the UN's Sustainable Development Goal 3 target to '… end preventable deaths of newborns and children under 5' and Goal 6 to '… ensure access to water and sanitation for all' by 2030.

Spatial and temporal patterns of dengue incidence in northeastern Thailand 2006-2016

Background

Dengue, a viral disease transmitted by Aedes mosquitoes, is an important public health concern throughout Thailand. Climate variables are potential predictors of dengue transmission. Associations between climate variables and dengue have usually been performed on large-scale first-level national administrative divisions, i.e. provinces. Here we analyze data on a finer spatial resolution in one province, which is often more relevant for effective disease control design. The objective of this study was to investigate the effect of seasonal variations, monthly climate variability, and to identify local clusters of symptomatic disease at the sub-district level based on reported dengue cases.

Methods

Data on dengue cases were retrieved from the national communicable disease surveillance system in Thailand. Between 2006 and 2016, 15,167 cases were recorded in 199 sub-districts of Khon Kaen Province, northeastern Thailand. Descriptive analyses included demographic characteristics and temporal patterns of disease and climate variables. The association between monthly disease incidence and climate variations was analyzed at the sub-district level using Bayesian Poisson spatial regression. A hotspot analysis was used to assess the spatial patterns (clustered/dispersed/random) of dengue incidence.

Results

Dengue was predominant in the 5–14 year-old age group (51.1%). However, over time, dengue incidence in the older age groups (> 15 years) gradually increased and was the most affected group in 2013. Dengue outbreaks coincide with the rainy season. In the spatial regression model, maximum temperature was associated with higher incidence. The hotspot analysis showed clustering of cases around the urbanized area of Khon Kaen city and in rural areas in the southwestern portion of the province.

Conclusions

There was an increase in the number of reported dengue cases in older age groups over the study period. Dengue incidence was highly seasonal and positively associated with maximum ambient temperature. However, climatic variables did not explain all the spatial variation of dengue in the province. Further analyses are needed to clarify the detailed effects of urbanization and other potential environmental risk factors. These results provide useful information for ongoing prediction modeling and developing of dengue early warning systems to guide vector control operations.

Electronic supplementary material

The online version of this article (10.1186/s12879-019-4379-3) contains supplementary material, which is available to authorized users.

Elevation of ambient temperature is associated with an increased risk of herpes zoster: a time-series analysis

Although varicella zoster (VZ) and herpes zoster (HZ) are caused by the same varicella zoster virus (VZV), the former is caused by primary infection while the latter is caused by reactivation of latent VZV, and their relationships with ambient temperature are also different. It is relatively well-established that VZ incidence declines with ambient temperature, but the relationship between HZ and ambient temperature is inconclusive. Thus, we investigated the effects of ambient temperature on the incidence of HZ in time-series analysis by using data from the Korean National Emergency Department Information System between 2014 and 2016. We applied a generalized linear model to investigate the relationship between ambient temperature and emergency room (ER) visits due to HZ, after controlling for confounders in seven metropolitan cities and nine provinces in South Korea. Region-specific estimates were pooled to obtain the national average estimates. There were a total of 61,957 ER visits nationwide for HZ during the study period. HZ significantly increased by 2.03% to 2.94% in the moving average lag models throughout 0 to 11 days with maximum percent increase of 2.94% (95% CI: 2.20, 3.68) in the 6-day moving average lag model.

Varicella in Tshuapa Province, Democratic Republic of Congo, 2009-2014

OBJECTIVE

To describe varicella cases in Tshuapa Province of the Democratic Republic of the Congo identified during monkeypox surveillance.

METHODS

Demographic, clinical and epidemiological data were collected from each suspected monkeypox case 2009-2014. Samples were tested by PCR for both Orthopoxviruses and varicella-zoster virus (VZV); a subset of VZV-positive samples was genotyped. We defined a varicella case as a rash illness with laboratory-confirmed VZV.

RESULTS

There were 366 varicella cases were identified; 66% were ≤19 years old. Most patients had non-typical varicella rash with lesions reported as the same size and stage of evolution (86%), deep and profound (91%), on palms of hands and/or soles of feet (86%) and not itchy (49%). Many had non-typical signs and symptoms, such as lymphadenopathy (70%) and sensitivity to light (23%). A higher proportion of persons aged ≥20 years than persons aged ≤19 years had ≥50 lesions (79% vs. 65%, P = 0.007) and were bedridden (15% vs. 9%, P = 0.056). All VZV isolates genotyped from 79 varicella cases were clade 5. During the surveillance period, one possible VZV-related death occurred in a 7-year-old child.

CONCLUSIONS

A large proportion of patients presented with non-typical varicella rash and clinical signs and symptoms, highlighting challenges identifying varicella in an area with endemic monkeypox. Continued surveillance and laboratory diagnosis will help in rapid identification and control of both monkeypox and varicella and improve our understanding of varicella epidemiology in Africa.

The use of antibiotics in the treatment of pediatric varicella patients: real-world evidence from the multi-country MARVEL study in Latin America & Europe

Background

Varicella is a highly contagious childhood disease. Generally benign, serious complications necessitating antibiotic use may occur. The objective of this study was to characterize the rate, appropriateness and patterns of real-world antibiotic prescribing for management of varicella-associated complications, prior to universal varicella vaccination (UVV) implementation.

Methods

Pooled, post-hoc analysis of 5 international, multicenter, retrospective chart reviews studies (Argentina, Hungary, Mexico, Peru, Poland). Inpatient and outpatient primary pediatric (1–14 years) varicella cases, diagnosed between 2009 and 2016, were eligible. Outcomes, assessed descriptively, included varicella-associated complications and antibiotic use. Three antibiotic prescribing scenarios were defined based on complication profile in chart: evidence of microbiologically confirmed bacterial infection (Scenario A); insufficient evidence confirming microbiological confirmation (Scenario B); no evidence of microbiological confirmation (Scenario C). Stratification was performed by patient status (inpatient vs. outpatient) and country.

Results

Four hundred one outpatients and 386 inpatients were included. Mean (SD) outpatient age was 3.6 (2.8) years; inpatient age was 3.1 (2.8) years. Male gender was predominant. Overall, 12.2% outpatients reported ≥1 infectious complication, 3.7% ≥1 bacterial infection, and 0.5% ≥1 microbiologically confirmed infection; inpatient complication rates were 78.8, 33.2 and 16.6%, respectively. Antibiotics were prescribed to 12.7% of outpatients and 68.9% of inpatients. Among users, β-lactamases (class), and clindamycin (agent), dominated prescriptions. Scenario A was assigned to 3.9% (outpatients) vs 13.2% (inpatients); Scenario B: 2.0% vs. 6.0%; Scenario C: 94.1% vs. 80.8%.

Conclusions

High rates of infectious complications and antibiotic use are reported, with low rates of microbiological confirmation suggesting possible antibiotic misuse for management of varicella complications.

Electronic supplementary material

The online version of this article (10.1186/s12889-019-7071-z) contains supplementary material, which is available to authorized users.

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.

Electronic supplementary material

The online version of this article (10.1186/s12889-019-6795-0) contains supplementary material, which is available to authorized users.

Effects of meteorological factor and air pollution on sudden sensorineural hearing loss using the health claims data in Busan, Republic of Korea

PURPOSE

Specific meteorological factors, including air pollution in the form of particulate matter (PM), affect the development of otologic disease and have adverse effects on the cardiovascular and respiratory systems. This study investigated relationships between the development of sudden sensorineural hearing loss(SSNHL) and meteorological factor with air pollution including PM.

MATERIALS AND METHODS

The daily patient number in 2015 admitted to the hospital with SSNHL were extracted from the Health Insurance Review and Assessment Service Bigdata in Busan. The meteorological factors and air pollution data of Busan area were obtained from meteorological stations in Busan. The relationship between the number of hospitalizations and the climatic factors was checked.

RESULTS

SSNHL patient group showed more common in women, and the highest rates were observed in patients in their 50s. The daily mean patient numbers were 2.27. The number of SSNHL patients in spring was statistically significantly higher than that in summer. The mean daily PM10 and PM2.5 concentrations were 48.0 and 29.4 μg/m³, respectively. The mean wind speed, maximum wind speed and daily atmospheric pressure range was weakly positively associated with SSNHL patient number. There were weak negative correlations between maximum PM2.5 and SSNHL admissions. The mean temperature and wind chill index showed non-significantly negative relationships with SSNHL admissions.

CONCLUSIONS

In Busan area, statistically significant weak relationships were detected between the daily numbers of patients admitted to the hospital with SSNHL and meteorological data, including PM level. Further investigation of these associations is required.

Susceptibility for varicella and factors associated with immunity among pregnant women in a tertiary care hospital in Sri Lanka- a cross-sectional study

BACKGROUND

Varicella during pregnancy can lead to serious maternal and fetal consequences. Although an effective vaccine is available it is not incorporated in to the routine vaccination programs in most of the Asian countries. Objectives of the study were to determine the susceptibility to varicella and factors associated with immunity, among a group of pregnant women attending to a tertiary care hospital in Sri Lanka.

METHODS

A hospital based descriptive cross sectional study was carried out at De Soyza maternity Hospital, Colombo. A sample of 385 pregnant women was selected. Data were collected through an interviewer administered questionnaire; presence of varicella IgG in blood was assessed by a validated commercial ELISA (Enzyme Linked Immunosorbant Assay.

RESULTS

The sample had a mean age of 28.5 years and majority was educated beyond General Certificate of Education (GCE) Ordinary Level. We found that 34% of study population was susceptible for the infection. A past history of varicella had a 89.5% positive predictive value and 53.1% negative predictive value for varicella immunity. Varicella sero-positivity was only associated with a lower educational level and number of childhood household members more than four. There was no association of sero-positivity with age.

CONCLUSION

This study demonstrates that a significant proportion of pregnant women of the study population are varicella-susceptible. Pre-pregnancy screening and preventive strategies including vaccination should be evaluated. History of past varicella infection could be a useful screening tool to exclude patients for vaccination.

Burden of varicella in the Asia-Pacific region: a systematic literature review

INTRODUCTION

Varicella is a highly contagious infection that can lead to serious complications, particularly in high-risk groups; however, it is vaccine preventable. Disease awareness and understanding of the disease burden can strongly influence vaccine coverage. This review provides insight into the current epidemiology and the importance of varicella from both public health and economic perspectives across the Asia-Pacific (APAC) region. Areas covered: A systematic literature review was conducted to identify studies on the incidence, seroprevalence, fatality rate and complication rate of varicella. Economic burden studies were also captured. Altogether, 125 studies were identified across the region; these were supplemented by government reports (gray data). Reported vaccine coverage varied from 2.8% to 97%; a key influencing factor was inclusion of the varicella vaccine in national immunization programs. In general, varicella incidence in the unvaccinated population was highest in children ≤5 years old and seroprevalence increased with age. Economic analyses highlighted the cost-saving potential of vaccination programs, especially from a societal perspective. Expert opinion: Varicella-related data varied greatly across the APAC region, highlighting the need to better understand the burden of varicella in this area, and particularly identified the need for better surveillance and reporting.

Herpesviridae Infection: Prevention, Screening, and Management

Bacterial, viral, and parasitic pathogens add significant morbidity and even mortality to pregnancy-with adverse effects extending to both the gravida and the newborn. Three herpesviruses deserve considerable attention given the effects of perinatal infection on obstetric outcomes, specifically maternal and neonatal morbidity. In the following review, we will provide a description of cytomegalovirus, herpes simplex virus, and varicella zoster virus. For each viral pathogen, we will describe the epidemiology, natural history, screening and diagnosis modalities, treatments, and implications for antepartum care. Furthermore, we will highlight future directions of work in reducing the morbidities associated with these viral pathogens.

Post-mortem detection of six human herpesviruses (HSV-1, HSV-2, VZV, EBV, CMV, HHV-6) in trigeminal and facial nerve ganglia by PCR

Background

Among over 100 types of Herpesviridae viruses, eight can infect humans: herpes simplex viruses (HSV-1, HSV-2), varicella zoster virus (VZV), cytomegalovirus (CMV), Epstein-Barr virus (EBV), and human herpesviruses 6, 7, and 8 (HHV-6, HHV-7, HHV-8). After initial infection, the viruses remain latent for the lifetime of the host. The aim of this study was to determine the distribution of six different herpesviruses: HSV-1, HSV-2, VZV, EBV, CMV, and HHV-6 in trigeminal and facial nerve ganglia among a random group of Polish population.

Methods

The studied group consisted of 47 individuals (40 male, seven female); mean age of 47.4 ± 16.5 years) who died of independent causes (suicide, traffic accident, and poisoning, among others). Bilateral trigeminal and facial nerve ganglia of each cadaver were collected during the autopsy. Herpesviruses were detected using multiplex polymerase chain reaction technique.

Results

Herpesviruses were found in trigeminal and/or facial ganglia in 30/47 (63.8%) of cadavers. HHV-6 was the most prevalent of the herpesviruses and was found in nearly half of cadavers (n = 22; 46.8%), followed by HSV-1 (n = 7; 14.9%), VZV (n = 4; 8.5%), EBV (n = 4; 8.5%), HSV-2 (n = 2; 4.3%), and CMV (n = 1; 2.1%). Facial nerve ganglia (n = 23; 48.9%) were more often infected than trigeminal ganglia (n = 13; 27.7%).

Discussion

The results of this study have revealed a common presence of the herpesviruses in trigeminal and facial nerve ganglia among a random group of Polish population. Furthermore, the data also demonstrate simultaneous infection of the ganglia with different herpesviruses. This study has contributed to the knowledge of prevalence and localization of herpesviruses in different structures of the nervous system.

Seroprevalence of varicella-zoster virus among pregnant women in Fayoum Governorate, Egypt

Background

Chickenpox infection acquired during pregnancy is a serious condition. There may be congenital malformations and neonatal varicella syndrome with significant morbidity and mortality. Egypt has no routine varicella-zoster vaccination program.

Objective

To assess the immune status against varicella-zoster virus (VZV) antibodies among a group of pregnant women and to study the relationship between VZV seroprevalence and some sociodemographic characteristics.

Subjects and methods

A descriptive cross-sectional study was conducted on a group of pregnant women (n = 333) attending antenatal care (ANC) clinic at Fayoum University Hospital. Serologic testing for VZV was performed using ELISA through the years 2016-2017.

Results

VZV seroprevalence was detected in 294 (88.3%) of the 333 recruited pregnant women. Older age > 25 years old was significantly associated with low percent of VZV-negative antibodies (6.7% in versus 17.4% in younger age, OR (95%CI) 0.34 (0.17-0.70)), also having more than one child was significantly associated with a low percent of VZV-negative antibodies (8.2% versus 16.1% among participants with no children or having one child, OR 0.34 (0.17-0.70)).

Conclusions

Despite the absence of a routine VZV vaccination program in Egypt, VZV immunity was high among pregnant women, but less than that reported in many developed countries. We recommend targeted vaccination for women in the reproductive age especially young and primipara.

Trial registration

Ethical Committee Registration number R67 session 42: date 12/11/2017(retrospectively registered).

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.

Varicella in the prison setting: A report of three outbreaks in Rhode Island and a review of the literature

BACKGROUND

The prison setting carries unique risks for varicella outbreaks and the disease in adults, particularly those who are immunocompromised, can be life-threatening. In 2016-17, there were three outbreaks of varicella at three different correctional facilities in Rhode Island. The Centers for Disease Control and Prevention (CDC) recommend post-exposure vaccination within three to five days for affected populations however the Federal Bureau of Prisons (BOP) notes the logistical challenges of vaccinating exposed incarcerated individuals.

MATERIAL AND METHODS

A descriptive analysis was performed for each outbreak along with an overview of the response. Varicella serologies were obtained from the exposed population at each facility and the results compiled for comparative analysis. A literature review was then performed to identify and analyze other reported varicella outbreaks in incarcerated populations.

RESULTS

In each outbreak, the sentinel event was an inmate with herpes zoster. In prison A, there were 432 inmates exposed to the virus leading to 5 cases of varicella, while the outbreak in Prison B exposed 46 inmates and led to 3 cases. In Prison C, there was one case of primary varicella and 97 inmates were exposed.

DISCUSSION

It is remarkable that there were 3 unrelated outbreaks in a short time and, although corroborating data would be necessary to establish a trend, it may signal an increased risk of varicella transmission within this population. Correctional facilities should remain vigilant and have plans for managing the disease including isolation protocols, serology testing and post-exposure vaccination when indicated. While the BOP does not provide clear recommendations on the use of post-exposure prophylaxis during an outbreak response in this population, the experience in Rhode Island and the review of the literate demonstrate steps that can be taken to facilitate a response including post-exposure vaccination in line with CDC recommendations.

Epidemiology and factors influencing varicella infections in tropical countries including Sri Lanka

Varicella zoster virus (VZV) infections occur worldwide but the epidemiology differs between different geographical regions. Epidemiology of varicella is partly understood in tropical and subtropical regions. Various hypotheses showing differences in exposure rates in different age groups have been proposed. Exposure to VZV during late childhood or adolescent stage causes high morbidity, especially in high school children, university students and young work force in tropical nations. Exposure to VZV infection or sero-prevalence rates through anti-VZV immunoglobulin G appears to be lower in Sri Lanka, similar to other tropical countries prior to the millennium. In contrast, a more recent study in a group of antenatal women showed a relatively higher exposure rate to VZV when compared to the exposure rates prior to 2004 in Sri Lanka. Climatic factors, socioeconomic conditions, mobility and cultural practices appear to play a role in the differences in the exposure rates to VZV infection in the tropics. In most tropical Asian countries including Sri Lanka, routine vaccination against varicella is not carried out. Individuals with negative history for varicella take the vaccine when there is a necessity. Medical and nursing students take the vaccine prior to their clinical training to avoid adulthood varicella.

Varicella infection in the Middle East: Prevalence, complications, and vaccination

Varicella (chickenpox) is the primary infection of varicella-zoster virus (VZV), it is a mild self-limiting infection, but it is also highly contagious and can cause severe complications among high-risk group of individuals. It is usually a childhood infection providing lifelong immunity, but adults without varicella history are also susceptible to infection. High-risk group of individuals is more likely to develop serious complications. Varicella vaccine was introduced to protect this group of individuals and to prevent epidemic spread of VZV infection in a community. Thus, it was added to the recommended vaccination schedules for children in most developed countries. This review aimed to outline varicella status, seroprevalence, complications, and vaccination in the Middle East region. Based on our findings, children were the most affected age group, but there are also adult cases due to high number of expatriates, especially in Gulf Cooperation Council countries. Central nervous system involvements and skin diseases followed by varicella pneumonia were the most varicella-associated complications. Varicella vaccine was introduced in most Middle East countries, either mandatory by the Ministries of Health or optional in the private clinics. Few numbers of studies have reported an obvious reduction in varicella prevalence, hospitalizations, and deaths in the Middle East following varicella vaccination. A basic database about varicella infection before the initiation and implementation of a vaccination policy is essential to determine the target group of individuals. As far as our knowledge, this is the first review about varicella infection in the Middle East.

Low Varicella Zoster Virus Seroprevalence Among Young Children in the Democratic Republic of the Congo

BACKGROUND

Varicella zoster virus (VZV) causes both varicella (chickenpox) and herpes zoster (shingles) and is associated with significant global morbidity. Most epidemiological data on VZV come from high-income countries, and to date there are limited data on the burden of VZV in Africa.

METHODS

We assessed the seroprevalence of VZV antibodies among children in the Democratic Republic of Congo in collaboration with the 2013-2014 Demographic and Health Survey. Dried blood spot samples collected from children 6-59 months of age were run on Dynex™ Technologies Multiplier FLEX® chemiluminescent immunoassay platform to assess serologic response. Multivariate logistic regression was then used to determine risk factors for VZV seropositivity.

RESULTS

Serologic and survey data were matched for 7,195 children 6-59 months of age, among whom 8% were positive and 2% indeterminate for VZV antibodies in weighted analyses. In multivariate analyses, the odds of seropositivity increased with increasing age, increasing socioeconomic status, mother's education level, rural residence, and province (South Kivu, North Kivu, Bandundu, Bas Congo had the highest odds of a positive test result compared with Kinshasa).

CONCLUSION

Our data suggest that VZV is circulating in DRC, and seropositivity is low among children 6-59 months. Seropositivity increased with age and varied by other sociodemographic factors, such as geographic location. This study provides the first nationally representative estimates of VZV infection among children in the DRC.

Varicella zoster virus-associated morbidity and mortality in Africa - a systematic review

BACKGROUND

Varicella zoster virus (VZV) causes varicella and herpes zoster. These vaccine preventable diseases are common globally. Most available data on VZV epidemiology are from industrialised temperate countries and cannot be used to guide decisions on the immunization policy against VZV in Africa. This systematic review aims to review the published data on VZV morbidity and mortality in Africa.

METHODS

All published studies conducted in Africa from 1974 to 2015 were eligible. Eligible studies must have reported any VZV epidemiological measure (incidence, prevalence, hospitalization rate and mortality rate). For inclusion in the review, studies must have used a defined VZV case definition, be it clinical or laboratory-based.

RESULTS

Twenty articles from 13 African countries were included in the review. Most included studies were cross-sectional, conducted on hospitalized patients, and half of the studies used varying serological methods for diagnosis. VZV seroprevalence was very high among adults. Limited data on VZV seroprevalence in children showed very low seropositivity to anti-VZV antibodies. Co-morbidity with VZV was common.

CONCLUSION

There is lack of quality data that could be used to develop VZV control programmes, including vaccination, in Africa.

TRIAL REGISTRATION

PROSPERO 2015: CRD42015026144 .

Serological Susceptibility to Varicella Among U.S. Immigration and Customs Enforcement Detainees

U.S. Immigration and Customs Enforcement (ICE) is responsible for detaining unauthorized aliens during immigration proceedings. During 2014 to 2015, adult ICE detainees at a California facility were invited to complete a survey concerning self-reported varicella history and risk factors. Participants underwent serological testing for varicella-zoster virus (VZV) IgG; susceptible individuals were offered varicella vaccination. Among 400 detainees with available serology results, 48 (12%) were susceptible to varicella. Self-reported varicella history was negatively associated with susceptibility (adjusted odds ratio = 0.16; 95% confidence interval [0.07, 0.35]). Among 196 detainees reporting a positive history, 95% had VZV IgG levels suggestive of varicella immunity. Among 44 susceptible detainees offered vaccination, 86% accepted. Given relatively high varicella susceptibility, targeted screening and vaccination among ICE detainees lacking a positive history might reduce varicella transmission risks.

Exposure rate of VZV among women attending antenatal care clinic in Sri Lanka - a cross sectional study

Background

Varicella or chickenpox was not a notifiable disease until 2005 in Sri Lanka and only a few studies have been conducted on the epidemiology of VZV infection in the country. The anti­VZV IgG sero-prevalence among antenatal women is extremely limited and thus a selected group of antenatal clinic attendees were chosen to determine the exposure rate to VZV infection.

Methods

Women attending the antenatal clinic at Teaching Hospital, Peradeniya, Sri Lanka were selected for the study and 3 mL of venous blood was collected from 181 participants and the demographic data was obtained through a pre­tested questionnaire. Sera of the women were then tested for the presence of anti­VZV IgG using ELISA (HUMAN Diagnostics, Germany). Data was analysed using the SPSS statistical software for Windows, Version 12.0.

Results

Of the 181 antenatal women who took part in the study, 141 were positive for anti­VZV IgG giving a sero-prevalence of 77.9% for the past exposure to VZV. Of the 141 anti­VZV IgG positive women, 43.3% (n = 61) were from urban, 41.8% (n = 59) were from rural and 14.9% (n = 21) were from estate populations (an ethnic population living in small settlements in the tea estates whose ancestors were brought from India during the British colonial period to work in the tea plantations in Sri Lanka). Out of the 88 antenatal women with a positive history for varicella, 85 (96.6%) were positive for anti-VZV IgG. The highest number of anti­VZV IgG positivity was seen in the 31–35 age group, which was 85.0% of the total number of antenatal women included in that category. An increase in the anti­VZV IgG sero-prevalence with increasing age was also noted in the study sample.

Conclusion

Exposure rate of VZV infection as confirmed by anti­VZV IgG in the present study sample of antenatal women was 77.9%. Age specific, population based future sero-prevalence studies should be conducted in Sri Lanka to understand the anti-VZV IgG status in the country.

Looking back to move forward: a twenty-year audit of herpes zoster in Asia-Pacific

Background

Herpes zoster (HZ) is a prevalent viral disease that inflicts substantial morbidity and associated healthcare and socioeconomic burdens. Current treatments are not fully effective, especially among the most vulnerable patients. Although widely recommended, vaccination against HZ is not routine; barriers in Asia-Pacific include long-standing neglect of adult immunisation and sparse local data. To address knowledge gaps, raise awareness, and disseminate best practice, we reviewed recent data and guidelines on HZ from the Asia-Pacific region.

Methods

We searched PubMed, Scopus, and World Health Organization databases for articles about HZ published from 1994 to 2014 by authors from Australia, China, Hong Kong, India, Indonesia, Japan, Korea, Malaysia, New Zealand, the Philippines, Singapore, Taiwan, Thailand, and Vietnam. We selected articles about epidemiology, burden, complications, comorbidities, management, prevention, and recommendations/guidelines. Internet searches retrieved additional HZ immunisation guidelines.

Results

From 4007 retrieved articles, we screened-out 1501 duplicates and excluded 1264 extraneous articles, leaving 1242 unique articles. We found guidelines on adult immunisation from Australia, India, Indonesia, Malaysia, New Zealand, the Philippines, South Korea, and Thailand.

HZ epidemiology in Asia-Pacific is similar to elsewhere; incidence rises with age and peaks at around 70 years – lifetime risk is approximately one-third. Average incidence of 3–10/1000 person-years is rising at around 5% per year. The principal risk factors are immunosenescence and immunosuppression. HZ almost always causes pain, and post-herpetic neuralgia is its most common complication. Half or more of hospitalised HZ patients have post-herpetic neuralgia, secondary infections, or inflammatory sequelae that are occasionally fatal. These disease burdens severely diminish patients’ quality of life and incur heavy healthcare utilisation.

Conclusions

Several countries have abundant data on HZ, but others, especially in South-East Asia, very few. However, Asia-Pacific countries generally lack data on HZ vaccine safety, efficacy and cost-effectiveness. Physicians treating HZ and its complications in Asia-Pacific face familiar challenges but, with a vast aged population, Asia bears a unique and growing burden of disease. Given the strong rationale for prevention, most adult immunisation guidelines include HZ vaccine, yet it remains underused. We urge all stakeholders to give higher priority to adult immunisation in general and HZ in particular.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-017-2198-y) contains supplementary material, which is available to authorized users.

Hidden varicella outbreak, Luang Prabang Province, the Lao People's Democratic Republic, December 2014 to January 2015

BACKGROUND

In January 2015, the Lao People's Democratic Republic Ministry of Health received a report of 34 cases of fever and rash with one laboratory-confirmed measles case in Houitone village, Pakseng District of Luang Prabang Province. Between 21 and 27 January, we conducted a field investigation to determine the etiology, magnitude and severity of this outbreak.

METHODS

We conducted active case findings in Houitone and neighbouring villages and collected information on age, location, date of rash onset, symptoms and measles vaccination status. We collected serum samples from cases with rash onset of less than 28 days and tested for measles and rubella IgM using enzyme-linked immunosorbent assay.

RESULTS

Between 22 December 2014 and 23 January 2015, 190 fever and rash cases were identified in seven villages in Pakseng District with the majority of the cases in Houitone village. The most affected age group was between 1 and 9 years. The majority of the rashes were vesicular. Of the additional 43 serum samples collected, no samples tested positive for measles or rubella IgM. The clinical manifestation and epidemiology of the disease suggested a varicella outbreak.

CONCLUSION

The rapid response to a single laboratory-confirmed measles case did not identify a measles outbreak but suggested a varicella outbreak. Low measles vaccination coverage led us to recommend a routine catch-up vaccination campaign. We also recommend collecting information of rash types and photos of rashes in future fever and rash outbreaks to better differentiate potential etiologies.

Prevalence and Characteristics of Pediatric Healthcare Workers without Immunity to Varicella zoster Virus

This study aimed to determine the proportion of varicella non-immune pediatric healthcare workers (HCWs) of the Pediatrics Department of King Chulalongkorn Memorial Hospital and to determine cost-effective strategies for identifying non-immune personnel. A cross-sectional study using a self-administered questionnaire to determine HCWs' histories of chickenpox or 2-dose varicella vaccination was conducted. From a total of 699 HCWs, 653 HCWs (93%), including 145 physicians (22%), 297 nurses (46%), and 211 administrative staff (32%), responded to questionnaires. There were 475 HCWs (73%) who had a history of chickenpox, 58 (9%) who had completed the 2-dose varicella vaccine schedule, and 120 (18%) whose varicella-zoster virus (VZV) immunity status was uncertain. In total, 107 HCWs (89%) were tested for VZV IgG, 90 of whom had immunity, and 17 were determined to be non-immune. After combining history and VZV IgG test results, the prevalence of non-immune HCWs was 2.6% (95%CI 1.4-3.8), with those ≤40 years of age at higher risk of non-immunity. Implementing a strategy that involves testing of only those with an unknown VZV status and vaccination for only those determined to be non-immune costs 1,801 United States dollar (USD), less than the total cost (4,601 USD) for vaccinating all HCWs with uncertain status.