The effects of ambient temperature on outpatient visits for varicella and herpes zoster in Shanghai, China: A time-series study

Evaluating public interest in herpes zoster in Germany by leveraging the internet: a retrospective search data analysis

BACKGROUND

Herpes zoster (HZ) and its complication postherpetic neuralgia (PHN), whose incidence are both expected to increase with an ageing population, have demonstrated high costs on healthcare systems and burden on individual quality of life. Previous studies have shown the possibility of assessing public interest in a disease and factors that influence search behaviour using internet search data. The aim of this study was to analyze internet search data for HZ in Germany to evaluate public interest in the disease and relevant influential temporal and geographic factors that modify search behavior.

METHODS

Google Ads Keyword Planner was used to generate a list of HZ-related keywords including their search volume for Germany as a whole and its sixteen federal states from October 2016 to September 2020. All keywords were qualitatively categorized, and changes over time and correlations with population density, physician density, and vaccination rates were assessed using Welch's ANOVA, Bonferroni correction for post-hoc analyses, and Pearson's correlation.

RESULTS

A total of 1,651 relevant keywords with a search volume of 20,816,210 searches were identified. Overall, national search volume increased each year of the study period with a peak in August 2020. More than half of the total search volume related to general queries (55.1%). The highest average monthly search volumes were observed in the states of Hamburg, Saarland, and Bremen. Average monthly search volume showed strong positive correlations with population density (r = .512, p = .043) and a strong negative correlation with the number of inhabitants per working physician (r = -.689, p = .003).

CONCLUSIONS

The study demonstrated that evaluating internet search data is a viable method for assessing public interest in HZ, thereby identifying areas of unmet need to support targeted public health campaigns.

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.

Effects of meteorological factors on the incidence of varicella in Lu'an, Eastern China, 2015-2020

Varicella (chickenpox) is a serious public health problem in China, with the most reported cases among childhood vaccine-preventable infectious diseases, and its reported incidence has increased over 20-fold since 2005. Few previous studies have explored the association of multiple meteorological factors with varicella and considered the potential confounding effects of air pollutants. It is the first study to investigate and analyze the effects of multiple meteorological factors on varicella incidence, controlling for the confounding effects of various air pollutants. Daily meteorological and air pollution data and varicella cases were collected from January 1, 2015, to December 31, 2020, in Lu'an, Eastern China. A combination of the quasi-Poisson generalized additive model (GAM) and distributed lag nonlinear model (DLNM) was used to evaluate the meteorological factor-lag-varicella relationship, and the risk of varicella in extreme meteorological conditions. The maximum single-day lag effects of varicella were 1.288 (95%CI, 1.201-1.381, lag 16 day), 1.475 (95%CI, 1.152-1.889, lag 0 day), 1.307 (95%CI, 1.196-1.427, lag 16 day), 1.271 (95%CI, 0.981-1.647, lag 4 day), and 1.266 (95%CI, 1.162-1.378, lag 21 day), when mean temperature, diurnal temperature range (DTR), mean air pressure, wind speed, and sunshine hours were -5.8°C, 13.5°C, 1035.5 hPa, 6 m/s, and 0 h, respectively. At the maximum lag period, the overall effects of mean temperature and pressure on varicella showed W-shaped curves, peaked at 17.5°C (RR=2.085, 95%CI: 1.480-2.937) and 1035.5 hPa (RR=5.481, 95%CI: 1.813-16.577), while DTR showed an M-shaped curve and peaked at 4.4°C (RR=6.131, 95%CI: 1.120-33.570). Sunshine hours were positively correlated with varicella cases at the lag of 0-8 days and 0-9 days when sunshine duration exceeded 10 h. Furthermore, the lag effects of extreme meteorological factors on varicella cases were statistically significant, except for the extremely high wind speed. We found that mean temperature, mean air pressure, DTR, and sunshine hours had significant nonlinear effects on varicella incidence, which may be important predictors of varicella early warning.

Ambient temperature exposure and risk of outpatient visits for dermatologic diseases in Xinxiang, China: a time-series analysis

The effect of ambient temperature on dermatologic diseases has received widespread attention. Previous studies have shown that ambient temperature might affect specific dermatologic diseases, but results were inconsistent. This study aims to assess the short-term effect of ambient temperature on outpatient visits due to dermatologic diseases (DMs) in Xinxiang, China. Daily DMs outpatient visits, mean temperature, mean relative humidity, and air pollution data of Xinxiang were retrieved from January 1, 2015, to December 31, 2018. A distributed lag nonlinear model (DLNM) was applied to analyze the effect of ambient temperature on DMs outpatients. We controlled several potential confounding factors such as the long-term trend, public holiday, day of the week, humidity, and air pollutants (NO₂, PM_2.5). Finally, two more stratification analysis was conducted by age and gender. A total of 164,270 outpatients of DMs were enrolled during our study, and the daily mean visits were 113. The estimated effect of temperature on DMs was nonlinear. Heat temperature would exacerbate outpatients of dermatologic diseases. With a reference median temperature (17 °C), the effect of temperature on DMs was most pronounced at lag0-14; exposure to heat (32 °C, 99th) was associated with 1.565 (95% CI: 1.266-1.934) increased risk of outpatients for DMs. Stratification analysis showed that citizens of young ages were susceptive to heat; both genders had a similar relationship between temperature and DMs risk. This study highlights that ambient temperature was associated with DMs outpatients; heat temperature might aggravate DMs risk. The health hazards of heat temperature required more attention, and more effective prevention measurements should be designed and implemented to curb global warming.

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.

The acute effects of ultraviolet radiation exposure on solar dermatitis in Shanghai, China

Ultraviolet radiation (UVR) has long been considered associated with solar dermatitis, but the associations have not been well quantified. To depict the full-range exposure-response association between daily UVR exposures and daily outpatient visits of solar dermatitis. We collected the daily number of outpatient visits of solar dermatitis and monitored hourly ground data of UVR (the sum of A- and B-band) from 1 January 2013 to 31 December 2017 in Shanghai, China. The data were analyzed using the time-series approach, in which overdispersed generalized additive model was used and time trends and weather conditions were controlled for. During the study period, we recorded a total of 15,051 outpatient visits of solar dermatitis. There was a consistently increasing risk of solar dermatitis associated with stronger UVR without a discernible threshold. The effects occurred on the present day, increased to the largest at lag 1 or 2 days, and attenuated to the null at lag 5 days or more. A unit (w/m²) increase in daily maximum-hour UVR was associated with 1.70% (95%CI: 1.19%, 2.20%) increase of outpatient visits of solar dermatitis. Stronger effects occurred among the young people, females, and in the warm season. The risks of solar dermatitis due to UVR exposure would be overestimated if ambient temperature was not adjusted. This study provides quantitative epidemiological estimates for the positive associations between short-term exposure to UVR and increased risks of solar dermatitis. The associations were more prominent among young people, females, and in warm seasons.

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.

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.

Infectious skin disorders encountered in a pediatric emergency department of a tertiary care hospital in Argentina: a descriptive study

BACKGROUND

Infectious skin disorders (ISDs) are commonly seen in pediatric emergency departments (PED), however the exact frequency is unknown. We provide an accurate evaluation of the incidence and characteristics of ISDs diagnosed in a PED from Buenos Aires, Argentina, over a 1-year period.

METHODS

Prospectively, descriptive study of children evaluated in the PED with ISDs during 2016. ISDs were analyzed on the basis of their incidence, patient demographics, seasonal variations, and hospitalization rates.

RESULTS

ISDs were diagnosed in 1680 (67.9%) of the skin consultations (M/F: 1.1; mean age: 4.4 ± 3.7 years). Bacterial infections were observed in 932 (55.5%) cases. Viral infections were seen in 604 patients (35.9%). Fungal and parasite skin infections were diagnosed in 33 (2%) and 111 (6.6%) children, respectively. The most frequent ISDs according to the etiology group were impetigo 377 (22.4%), varicella 397 (23.6%), tinea capitis 10 (0.6%), and scabies 109 (6.5%). A higher frequency of ISDs were reported during the summer (38.4%) and spring (38.2%) months. Bacterial skin infections were more frequent during the summer months, while viral skin infections were more prevalent during spring. Parasitic skin infections were diagnosed more frequently during the winter months. No differences were seen for mycotic skin infections. Hospitalization rate was 1% (all for bacterial skin infections).

CONCLUSION

Our data reveal the extremely high frequency of ISDs seen at the PED, underlying the need for closer cooperation between dermatologists and pediatricians.

Risk Factors for Herpes Zoster: A Systematic Review and Meta-analysis

OBJECTIVE

To systematically review studies examining risk factors for herpes zoster (HZ).

METHODS

We performed a literature search using PubMed, EMBASE, and Web of Science for articles published from January 1, 2003, to February 1, 2017. A random-effects model was used to summarize the risk ratio (RR) or odds ratio (OR) and 95% CI.

RESULTS

Of the 3450 studies screened, we included 84 studies in the systematic review and conducted meta-analysis in 62 studies. Women were at increased risk of HZ compared with men (pooled adjusted RR, 1.31; 95% CI, 1.27-1.34). Black individuals had almost half the risk of HZ as white individuals (pooled RR, 0.54; 95% CI, 0.47-0.63). Family history was found to be a risk factor for HZ (pooled OR, 3.59; 95% CI, 2.39-5.40). Autoimmune diseases, including rheumatoid arthritis (pooled RR, 1.67; 95% CI, 1.41-1.98) and systemic lupus erythematosus (pooled RR, 2.10; 95% CI, 1.40-3.15), were associated with an elevated risk of HZ. Other comorbidities were associated with an increased risk of HZ, with the pooled RRs ranging from 1.25 (95% CI, 1.13-1.39) for asthma to 1.30 (95% CI, 1.17-1.45) for diabetes mellitus and 1.31 (95% CI, 1.22-1.41) for chronic obstructive pulmonary disease.

CONCLUSION

Our review revealed that female sex, race/ethnicity, family history, and comorbidities are risk factors for HZ. Efforts are needed to increase the uptake of zoster vaccination.

Seroprevalence and Risk Factors of Varicella Zoster Infection in Iranian Adolescents: A Multilevel Analysis; The CASPIAN-III Study

The objective of this study was to evaluate the varicella zoster virus (VZV) immunity in Iranian adolescents. It was conducted as a primary study for vaccine implementation, and to investigate the association of climatic and socioeconomic factors with the epidemiology of this infection. In this cross- sectional study, anti VZV antibodies were measured in serum samples obtained in a national school-based health survey (CASPIAN- III). Association of demographic, socio-economic, and climate of the living region with the frequency of VZV was investigated by multivariate multilevel analysis. Overall, sera of 2753 individuals aged 10–18 were tested for VZV antibodies, from those 87.4% were positive. The prevalence was statistically different in four socio-geographic regions (P<0.001), varying between 85.24% in West region (mostly mountainous areas with cold climate) to 94.59% in Southeast region (subtropical climate). Among variables studied, only age and mean daily temperature of the living area were positively associated with the VZV seroprevalence. Our findings show that most Iranians develop immunity to VZV before the age of 10, but a substantial proportion of them are yet susceptible to the infection. Therefore, it seems that the best strategy to reduce the burden of the disease is to vaccinate high- risk adults, i.e. those without a history of varicella infection. The regional temperature might be the only determinant of VZV epidemiology in Iran.