Varicella-Zoster Virus in Perth, Western Australia: Seasonality and Reactivation

Association between Meteorological Factors and Outpatient Visits for Herpes Zoster in Hefei, China: A Time-Series Analysis

This study sought to investigate the relationship between meteorological factors and outpatient visits for herpes zoster. In this time-series analysis, we used data from two major hospitals in Hefei, collected between 2015 and 2019, to evaluate the impact of meteorological factors on the risk of herpes zoster. After controlling for confounders, we adopted a distributed lag nonlinear model to probe the relationship between meteorological factors and outpatient visits for herpes zoster. The analysis was stratified according to age (<40 years, ≥40 years) and sex (male, female). A total of 43,547 cases of herpes zoster were reported, and compared with the median value, a high temperature and high relative humidity had a significant risk effect on the incidence of herpes zoster. The maximum harmful effect of high temperature on herpes zoster occurred on the lag0 (RR: 1.027, 95% CI: 1.002-1.053) and further declined over the following days. The cumulative effect increased with the extension of lag days, and the cumulative RR was the largest on the sixth day of lag (RR1.031, 95% CI: 1.006-1.056) when the relative humidity was 85.7% (77.0% as the reference). The stratified analysis results reveal that females and the elderly (≥40 years) were more susceptible to temperature and relative humidity. This study shows that high-temperatures may lead to herpes zoster, indicating that those infected with varicella zoster virus need to take measures over the course of several days when not exposed to the best appropriate temperature conditions.

Meningitis/meningoencephalitis caused by varicella zoster virus reactivation: a retrospective single-center case series study

Recent clinical studies showed that central nervous system (CNS) infection caused by varicella zoster virus (VZV) reactivation was more than previously reported. The clinical manifestations were often diverse and complex, and the outcome often varied among different patients. A systematic study is needed to provide clinical characteristics of the CNS VZV infection to help clinicians with clinical diagnosis and management. Toward that end, we retrospectively analyzed the clinical presentations, laboratory results, imaging findings, treatment and outcomes in74 patients with meningitis or meningoencephalitis caused by VZV reactivation in our center from August 2018 to December 2020. Fever, headache, cranial nerve involvement, cognitive changes, meningeal irritation, nausea, vomiting, and Ramsay-Hunt syndrome (RHS) were the most common clinical manifestations of VZV meningitis or meningoencephalitis. Brain MRI analysis showed no obvious abnormal manifestation. Compared to VZV meningoencephalitis, patients with VZV meningitis were younger (56.9±13.8 vs 66.1±8.5 years; P=0.01), and more likely to develope in winter (P=0.04), had lower cerebrospinal fluid (CSF) glucose content (3.68±0.79 vs 4.21±0.94 mmol/L, P=0.02), and a better outcome at discharge (P=0.00). The outcome at discharge was worse in male patients and when longer than 1.5 days passed between onset of the neurological symptoms to initiation of the antiviral treatment.Early intravenous antiviral treatment for VZV meningitis and meningoencephalitis is important and is expected for a good outcome.

The impacts of ambient temperature and ultraviolet radiation on the incidence of herpes zoster: An ecological study in Taiwan

The aim of the study was to examine the relationship between ambient temperature, ultraviolet radiation, and the development of herpes zoster in Taiwan. An ecological study was conducted to analyse the database of the Taiwan National Health Insurance Programme. Participants aged ≥20 years with newly diagnosed herpes zoster between 2003 and 2012 were selected for analysis. The monthly incidence rate of herpes zoster was measured between 2003 and 2012. Monthly average ambient temperature in Celsius (°C) between 2003 and 2012 was measured according to the official database of the Central Weather Bureau in Taiwan. Monthly accumulated ultraviolet radiation (MJ m^-2 ) between 2003 and 2012 was measured according to the official database of the Environmental Protection Administration in Taiwan. The overall incidence rates of herpes zoster ranged from 2.54 to 5.67 per 10 000 persons per month from 2003 to 2012.The monthly average ambient temperature was higher and the monthly accumulated ultraviolet radiation was stronger from May to October. The incidence rates of herpes zoster seemed to be high during the period of high ambient temperature and strong ultraviolet radiation (from May to October).Whenever ambient temperature increased 1°C per month, the incidence rate of herpes zoster increased by 0.072 per 10,000 persons per month. Whenever ultraviolet radiation increased 1 MJ m^-2 per month, the incidence rate of herpes zoster increased by 0.313 per 10 000 persons per month. There is a significant association between ambient temperature, ultraviolet radiation, and the development of herpes zoster in Taiwan. The incidence rate of herpes zoster is high during the period of high ambient temperature and strong ultraviolet radiation. Low ambient temperature and weak ultraviolet radiation might be beneficial for the prevention of herpes zoster.

Seasonal dynamics of varicella incidence in Bulgaria

Aim: Spatial and temporal distribution of varicella is heterogenic and insufficiently studied in Europe. The present study tries to fill the gap that exists about the seasonality of the infection in Bulgaria. Materials & methods: A 4-year retrospective study of the monthly and seasonal varicella epidemiology was performed at both national and district level. Results: In Bulgaria, varicella incidence peaked during winter (37% of the 2015–2018 cases), followed by spring (33%) and autumn (23%). Highly populated districts were more likely to follow this pattern, while less inhabited districts with smaller urbanized areas showed different periodicity of the infection. Conclusion: Winter peak in varicella incidence is positively associated with high accumulation of people in the large cities (>75,000 inhabitants).

Seasonality of herpes zoster and herpes zoster ophthalmicus

BACKGROUND

Herpes zoster (HZ) and herpes zoster ophthalmicus (HZO) are common and debilitating diseases. There is no consensus in the literature whether HZ and HZO exhibit seasonal patterns.

OBJECTIVES

To determine whether HZ and HZO are seasonal.

STUDY DESIGN

All patients in the OptumLabs® Data Warehouse (OLDW), a longitudinal, insurance claims database with de-identified lives between January 1, 2006 and December 31, 2017 with 365 days or more of continuous enrollment were considered in the study. The database was queried for patients reporting a new ICD-9/ICD-10 code for HZ or HZO and monthly counts of each administrative code were modeled using Morelet wavelets and analyzed for annual periodicity using Fisher's g test.

RESULTS

There were a total of 513,911 new cases of HZ during this time period; 40,166 cases (7.8 %) were reported as HZO. Administrative coding for new cases of HZ exhibited annual periodicity (P < .001) with a peak in the summer. No periodicity was evident for HZO.

CONCLUSIONS

These results contribute to a growing body of evidence suggesting that HZ may be seasonal and help characterize the epidemiology of this common, painful disease.

Seasonality of Acute Retinal Necrosis

Purpose

To study the seasonal variability in the occurrence of acute retinal necrosis (ARN) in a series of polymerase chain reaction (PCR)-positive patients.

Methods

Consecutive patients clinically diagnosed with ARN and a positive PCR result of aqueous humor during a seven-year period were studied retrospectively. Patients' demographics, causative viral agent(s), and the date of disease onset were extracted from medical records.

Results

Twenty eyes of 20 patients were enrolled; the mean age at presentation was 39.6 ± 14.4 (range, 6–62) years. Nine patients were female. The most common causative agent was varicella-zoster virus in 16 patients (80%), followed by herpes simplex virus in two patients (10%). The disease onset was in winter in 10 patients (50%), and the highest incidence was in February (five patients, 25%). The cumulative occurrence of ARN was significantly higher in the first half of the year (winter and spring) compared to the second half of the year (summer and fall) (P = 0.030). In general, seasons with a high incidence of ARN were preceded by cold seasons.

Conclusion

In our series, we observed seasonal variability in the incidence of ARN, with the highest incidence during winter and spring. However, further epidemiologic studies in different geographical areas are required to elucidate the true seasonal nature of ARN.

Ultraviolet Radiation Exposure and the Risk of Herpes Zoster in Three Prospective Cohort Studies

OBJECTIVE

To examine the association between ultraviolet radiation (UVR) exposure and the risk of herpes zoster (HZ) in 3 prospective cohorts.

PATIENTS AND METHODS

We included 205,756 participants from the Health Professionals Follow-up Study (HPFS; 1986-2008), Nurses' Health Study (NHS; 1996-2012), and Nurses' Health Study II (NHS II; 1991-2013). Ambient UVR exposure was based on updated geocoded address histories linked with a high-resolution spatiotemporal ultraviolet model. Incident HZ cases were identified by self-reported clinician diagnosis. Sunburn history and medical, lifestyle, and dietary factors were assessed using biennial questionnaires. Multivariable Cox proportional hazards models were used.

RESULTS

A total of 24,201 cases of HZ occurred during 3,626,131 person-years. Ambient UVR exposure was associated with a higher risk of HZ in men (HPFS: multivariable-adjusted hazard ratio [MVHR] comparing highest vs lowest quintiles, 1.14; 95% CI, 1.02-1.29; P=.03 for trend) but not in women (NHS: MVHR, 0.99; 95% CI, 0.93-1.05; NHS II: MVHR, 0.96; 95% CI, 0.90-1.03). A higher lifetime number of severe sunburns was associated with a higher risk of HZ in all cohorts (HPFS: MVHR for ≥10 sunburns vs none, 1.08; 95% CI, 0.96-1.20; P=.02 for trend; NHS: MVHR, 1.14; 95% CI, 1.05-1.22; P=.01 for trend; NHS II: MVHR, 1.13; 95% CI, 1.00-1.28; P<.001 for trend).

CONCLUSION

Ambient UVR exposure was associated with a higher risk of HZ in men but not in women. A history of severe sunburn was associated with a modest increased risk of HZ in men and women, possibly because of immunosuppression from overexposure to the sun.

Are there differences in immune responses following delivery of vaccines through acutely or chronically sun-exposed compared with sun-unexposed skin?

The majority of human vaccines are administered above the deltoid muscle of the arm, a site that is chronically sun-exposed in many people. It is known that exposure of the skin to the UV wavelengths in sunlight stimulates systemic immunosuppression, an outcome that is associated with reduced immunity to microbial infections in animal models. Here we consider whether immunization of humans through a UV-irradiated skin site will lead to a less effective immune response compared with immunization through an unexposed site. Studies showing that the efficacy of vaccination can be reduced when surrogates of increased levels of sun exposure, such as latitude of residence and season of the year, are considered. Results from a limited number of intervention experiments in humans demonstrate a similar pattern. To provide an explanation for these findings, changes in the number and functional potential of immune cells in chronically sun-exposed compared with unexposed skin are outlined. UV radiation-induced changes to skin cells are also relevant when considering skin sites for administration of immune-tolerizing peptides. The review provides the basis for further research into the effects of acute and chronic UV radiation exposure on skin cells in the context of vaccination.

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.

Photoimmunology: how ultraviolet radiation affects the immune system

Ultraviolet (UV) radiation is a ubiquitous component of the environment that has important effects on a wide range of cell functions. Short-wavelength UVB radiation induces sunburn and is a potent immunomodulator, yet longer-wavelength, lower-energy UVA radiation also has effects on mammalian immunity. This Review discusses current knowledge regarding the mechanisms by which UV radiation can modify innate and adaptive immune responses and how this immunomodulatory capacity can be both beneficial in the case of inflammatory and autoimmune diseases, and detrimental in the case of skin cancer and the response to several infectious agents.

Human health in relation to exposure to solar ultraviolet radiation under changing stratospheric ozone and climate

The Montreal Protocol has limited increases in the UV-B (280-315 nm) radiation reaching the Earth's surface as a result of depletion of stratospheric ozone. Nevertheless, the incidence of skin cancers continues to increase in most light-skinned populations, probably due mainly to risky sun exposure behaviour. In locations with strong sun protection programs of long duration, incidence is now reducing in younger age groups. Changes in the epidemiology of UV-induced eye diseases are less clear, due to a lack of data. Exposure to UV radiation plays a role in the development of cataracts, pterygium and possibly age-related macular degeneration; these are major causes of visual impairment world-wide. Photodermatoses and phototoxic reactions to drugs are not uncommon; management of the latter includes recognition of the risks by the prescribing physician. Exposure to UV radiation has benefits for health through the production of vitamin D in the skin and modulation of immune function. The latter has benefits for skin diseases such as psoriasis and possibly for systemic autoimmune diseases such as multiple sclerosis. The health risks of sun exposure can be mitigated through appropriate sun protection, such as clothing with both good UV-blocking characteristics and adequate skin coverage, sunglasses, shade, and sunscreen. New sunscreen preparations provide protection against a broader spectrum of solar radiation, but it is not clear that this has benefits for health. Gaps in knowledge make it difficult to derive evidence-based sun protection advice that balances the risks and benefits of sun exposure.

The impact of childhood varicella vaccination on the incidence of herpes zoster in the general population: modelling the effect of exogenous and endogenous varicella-zoster virus immunity boosting

Background

A controversy exists about the potential effect of childhood varicella vaccination on Herpes Zoster (HZ) incidence. Mathematical models projected temporary HZ incidence increase after vaccine introduction that was not confirmed by real-world evidence. These models assume that absence of contacts with infected children would prevent exogenous boosting of Varicella-Zoster-Virus (VZV) immunity and they do not include an endogenous VZV immunity-boosting mechanism following asymptomatic VZV reactivation. This study aims to explore the effect of various assumptions on exogenous and endogenous VZV immunity-boosting on HZ incidence in the general population after introduction of routine childhood varicella vaccination.

Methods

An age-structured dynamic transmission model was adapted and fitted to the seroprevalence of varicella in France in absence of vaccination using the empirical contact matrix. A two-dose childhood varicella vaccination schedule was introduced at 12 and 18 months. Vaccine efficacy was assumed at 65%/95% (dose 1/dose 2), and coverage at 90%/80% (dose 1/dose 2). Exogenous boosting intensity was based on assumptions regarding HZ-immunity duration, age-dependent boosting effect, and HZ reactivation rates fitted to observed HZ incidence. Endogenous boosting was the same as pre-vaccination exogenous boosting but constant over time, whilst exogenous boosting depended on the force of infection. Five scenarios were tested with different weightings of exogenous (Exo) - endogenous (Endo) boosting: 100%Exo–0%Endo, 75%Exo–25%Endo, 50%Exo–50%Endo, 25%Exo–75%Endo, 0%Exo–100%Endo.

Results

HZ incidence before varicella vaccination, all ages combined, was estimated at 3.96 per 1000 person-years; it decreased by 64% by year 80 post vaccine introduction, for all boosting assumptions. The 100%Exo-0%Endo boosting scenario, predicted an increase in HZ incidence for the first 21 years post vaccine introduction with a maximum increase of 3.7% (4.1/1000) at year 9. However, with 0%Exo-100%Endo boosting scenario an immediate HZ decline was projected. The maximum HZ incidence increases at 10, 3, and 2 years post vaccination were 1.8% (75%Exo-25%Endo), 0.8% (50%Exo-50%Endo) and 0.2% (25%Exo-75%Endo), respectively.

Conclusions

Assuming modest levels of endogenous boosting, the increase in HZ incidence following childhood varicella vaccination was smaller and lasted for a shorter period compared with 100%Exo-0%Endo boosting assumption. Endogenous boosting mechanism could partly explain the divergence between previous HZ-incidence projections and real-world evidence.

Electronic supplementary material

The online version of this article (10.1186/s12879-019-3759-z) contains supplementary material, which is available to authorized users.

Exposure to Ultraviolet Radiation in the Modulation of Human Diseases

This review focuses primarily on the beneficial effects for human health of exposure to ultraviolet radiation (UVR). UVR stimulates anti-inflammatory and immunosuppressive pathways in skin that modulate psoriasis, atopic dermatitis, and vitiligo; suppresses cutaneous lesions of graft-versus-host disease; and regulates some infection and vaccination outcomes. While polymorphic light eruption and the cutaneous photosensitivity of systemic lupus erythematosus are triggered by UVR, polymorphic light eruption also frequently benefits from UVR-induced immunomodulation. For systemic diseases such as multiple sclerosis, type 1 diabetes, asthma, schizophrenia, autism, and cardiovascular disease, any positive consequences of UVR exposure are more speculative, but could occur through the actions of UVR-induced regulatory cells and mediators, including 1,25-dihydroxy vitamin D₃, interleukin-10, and nitric oxide. Reduced UVR exposure is a risk factor for the development of several inflammatory, allergic, and autoimmune conditions, including diseases initiated in early life. This suggests that UVR-induced molecules can regulate cell maturation in developing organs.

Monitoring Interest in Herpes Zoster Vaccination: Analysis of Google Search Data

Background

A new recombinant subunit vaccine for herpes zoster (HZ or shingles) was approved by the United States Food and Drug Administration on October 20, 2017 and is expected to replace the previous live attenuated vaccine. There have been low coverage rates with the live attenuated vaccine (Zostavax), ranging from 12-32% of eligible patients receiving the HZ vaccine.

Objective

This study aimed to provide insight into trends and potential reasons for interest in HZ vaccination.

Methods

Internet search data were queried from the Google Health application programming interface from 2004-2017. Seasonality of normalized search volume was analyzed using wavelets and Fisher’s g test.

Results

The search terms “shingles vaccine,” “zoster vaccine,” and “zostavax” all exhibited significant periodicity in the fall months (P<.001), with sharp increases after recommendations for vaccination by public health-related organizations. Although the terms “shingles blisters,” “shingles itch,” “shingles rash,” “skin rash,” and “shingles medicine” exhibited statistically significant periodicities with a seasonal peak in the summer (P<.001), the terms “shingles contagious,” “shingles pain,” “shingles treatment,” and “shingles symptoms” did not reveal an annual trend.

Conclusions

There may be increased interest in HZ vaccination during the fall and after public health organization recommendations are broadcast. This finding points to the possibility that increased awareness of the vaccine through public health announcements could be evaluated as a potential intervention for increasing vaccine coverage.

Environmental effects of ozone depletion and its interactions with climate change: Progress report, 2016

The Parties to the Montreal Protocol are informed by three Panels of experts. One of these is the Environmental Effects Assessment Panel (EEAP), which deals with two focal issues. The first focus is the effects of UV radiation on human health, animals, plants, biogeochemistry, air quality, and materials. The second focus is on interactions between UV radiation and global climate change and how these may affect humans and the environment. When considering the effects of climate change, it has become clear that processes resulting in changes in stratospheric ozone are more complex than previously believed. As a result of this, human health and environmental issues will be longer-lasting and more regionally variable. Like the other Panels, the EEAP produces a detailed report every four years; the most recent was published as a series of seven papers in 2015 (Photochem. Photobiol. Sci., 2015, 14, 1-184). In the years in between, the EEAP produces less detailed and shorter Progress Reports of the relevant scientific findings. The most recent of these was for 2015 (Photochem. Photobiol. Sci., 2016, 15, 141-147). The present Progress Report for 2016 assesses some of the highlights and new insights with regard to the interactive nature of the direct and indirect effects of UV radiation, atmospheric processes, and climate change. The more detailed Quadrennial Assessment will be made available in 2018.