Effect of diurnal temperature range on emergency room visits for acute upper respiratory tract infections

BACKGROUND@#An acute upper respiratory tract infection (URI) is the most common disease worldwide, irrespective of age or sex. This study aimed to evaluate the short-term effect of diurnal temperature range (DTR) on emergency room (ER) visits for URI in Seoul, Korea, between 2009 and 2013.@*METHODS@#Daily ER visits for URI were selected from the National Emergency Department Information System, which is a nationwide daily reporting system for ER visits in Korea. URI cases were defined according to International Classification of Diseases, 10@*RESULTS@#There were 529,527 ER visits for URI during the study period, with a daily mean of 290 visits (range, 74-1942 visits). The mean daily DTR was 8.05 °C (range, 1.1-17.6 °C). The cumulative day (lag 02) effect of DTR above 6.57 °C per 1 °C increment was associated with a 1.42% (95% confidence interval [CI] 0.04-2.82) increase in total URI. Children (≤ 5 years of age) were affected by DTR above 6.57 °C per 1 °C, with 1.45% (95% CI 0.32-2.60) at lag 02, adults (19-64 years) with 2.77% (95% CI 0.39-5.20) at lag 07. When the DTR (lag02) was 6.57 °C to 11.03 °C, the relative risk was significant at 6.01% (95% CI 2.45-9.69) for every 1 °C increase in youth subjects aged for 6 to 18 years.@*CONCLUSIONS@#DTR was associated with a higher risk for ER visits for URI. In addition, the results suggested that the lag effects and relative risks of DTR on URI were quite different according to age.

Effects of climate variables on the incidence of scorpion stings in Iran for five years

Background: Although scorpionism is recorded worldwide, some regions such as Iran present a higher incidence. Due to the great prevalence of scorpion stings in Khuzestan province, southwestern Iran, the present study examined the relationship between different climate parameters and the scorpion sting rate in this area from April 2010 to March 2015. Methods: In this cross-sectional descriptive-analytical study, we considered all scorpion sting cases recorded in the Department of Infectious Diseases, Ahvaz Jundishapur University of Medical Sciences. Data were analyzed using statistics, frequency distribution and Pearson's correlation coefficient. Results: A total of 104,197 cases of scorpion stings was recorded from 2010 to 2015. The cumulative incidence of scorpion sting was 2.23%. The spatial distribution of scorpion stings showed that most cases occurred in the Dehdez district (4,504 scorpion stings/100,000 inhabitants) and the Masjed Soleyman county (4,069 scorpion stings/100,000 inhabitants). A significant association was found between climate factors (temperature, evaporation rate, sunshine duration, humidity, and precipitation) and the scorpion sting rate. An increase in rainfall and humidity coincided with a reduction in scorpion stings whereas an increase in temperature, evaporation, and sunshine duration was accompanied by a growth of scorpion stings. No significant correlation was found between wind velocity/direction and the incidence rate of stings. Moreover, the seasonal peak incidence of scorpion stings was recorded in summer (an average of 8,838 cases) and the lowest incidence was recorded during winter (an average of 1,286 cases). The annual trend of scorpion sting cases decreased during the period from 2010 to 2015. Conclusion: Climate variables can be a good index for predicting the incidence of scorpion stings in endemic regions. Since they occur mostly in the hot season, designing preventive measures in the counties and districts with a high incidence of scorpion stings such as Dehdez and Masjed Soleyman can minimize mortality and other burdens.(AU)

Grey correlation analysis and path analysis between isoflavones content in Astragali Radix and climate factors / 中国中药杂志

In this study, HPLC was used to determine the content of the four isoflavones of Astragalus membranceus var. mongholicus from different regions(calycosin-7-glucoside, ononin, calycosin and formononetin), and gray correlation analysis and path analysis were used to explore the influence of climate factors on the content of isoflavone components in A. membranceus var. mongholicus. The results showed that there were significant differences in the content of the four isoflavones in different areas(P<0.05); grey correlation analysis showed that the highest temperature in July, the lowest temperature in January and the daily average temperature had a greater impact on the content of flavonoid glycosides, meanwhile precipitation and relative humidity were the more important factors for the accumulation of flavonoid aglycones. According to the general analysis, the direct positive effects of the lowest temperature in January and altitude on the contents of four isoflavones in A. membranceus var. mongholicus were significant. High altitude and extreme temperature conditions might be more adverse to the formation and accumulation of isoflavone components. Therefore, the religions of A. membranceus var. mongholicus with high contents of isoflavones should be chosen the low altitude region with higher minimum temperature in January. This study provides a reference basis for the quality evaluation of A. membranceus var. mongholicus, and basic data for the selection of suitable habitat, construction of planting standards and directional cultivation of medicinal materials in A. membranceus var. mongholicus.

Correlation of respiratory syncytial virus infection with climate parameters and air pollution levels in Korean children during 2005–2012

PURPOSE: Respiratory syncytial virus (RSV) is the major cause of acute lower respiratory tract infection (LRTI) in infants and children. We investigated the association of meteorological conditions and air pollution with the prevalence of RSV infection. METHODS: Between January 2005 and December 2012, a total of 9,113 nasopharyngeal swab specimens from children under 3 years of age who were admitted to the hospital with acute LRTI were tested for RSV antigens using a direct immunofluorescence kit. Meteorological data (mean temperature, precipitation, wind speed, and relative humidity) and air pollutant levels including PM₁₀ (particulate matter with a median aerodynamic diameter less than or equal to 10 µm in diameter), nitrogen dioxide (NO₂), sulfur dioxide (SO₂), and carbon monoxide (CO) in Seoul during the study period were collected from the national monitoring system. The correlations of the monthly incidence of RSV infection with climate factors and air pollutant levels were analyzed. RESULTS: RSV infection mainly occurred between October and February, and showed the peak in November. The prevalence of RSV infection had a moderate negative correlation with mean temperature (r=−0.60, P < 0.001), a weak negative correlation with relative humidity (r=−0.26, P=0.01), and precipitation (r=−0.34, P=0.001). Regarding air pollutants, RSV activity moderately correlated with NO₂ (r=0.40, P < 0.001), SO₂ (r=0.41, P < 0.001), and CO (r=0.58, P < 0.001). In the RSV peak season in Korea (between October and February), RSV epidemics showed a weak positive correlation with relative humidity (r=0.35, P=0.03) and precipitation (r=0.38, P=0.02). CONCLUSION: Meteorological factors and air pollutant levels may be associated with RSV activity. Therefore, further nationwide large-scaled intensive evaluations to prove factors affecting RSV activity are warranted.

Review on the climate factors-based flu epidemic prediction / 国际中医中药杂志

Epidemic influenza (flu) is a disease threatening the life of people for a long history.A precise forecast for the flu outbreak can warn and help health care providers to take measures to reduce the influences and harms in advance.At present,with the development of information technology,there have accumulated tremendous data of flu trends and climate information.With a history of 90 years researches about the forecast of flu trends,researchers have put forward different types of forecasting methods,and each of them has merits and demerits.Among these methods,those ones considering the key climate factors have higher precisions.Considering various methods at present,the prediction accuracy can be improved mainly from two aspects:on one hand,the forecast accuracy can be improved by effectively integrate the advantages of different models ; On the other hand,the prediction must take into account of the specific climate of an area,pathogens and the mode of transmission characteristics in order to determine the most relevant climate factors or other highly related factors with which to design a more reasonable and accurate prediction method.

A retrospective analysis on the association between seasonality of influenza A and climate factors in human from 1997 to 2008,in Hong Kong / 中华流行病学杂志

Objective To investigate the association between seasonal dynamics of influenza A and climate factors in Hong Kong.Methods Data regarding monthly report on influenza A and climate during the period of 1997-2008 were collected.Generalized additive models were established to study the effects of climate factors on the seasonality of influenza A in human while confounders controlled and nonlinear effect determined.Results Results showed that the association between climate factors and the seasonality of influenza A was complicated.The nonlinear effects of climate factors on the epidemics of influenza A were significant,using x2 test (P＜0.05).The effect of the factors including mean temperature,relative humidity,wind speed and absolute humidity on the seasonality of influenza A were similar,maximal at low scale,minimal at mid-rang scale and moderate at high one.The minamal effect intervals of the above factors were (17.95-24.10) ℃,(71.5-78.5 )％,(18.3-24.0) km/h and (4.37-4.80)mb respectively.Conclusion Data from this study suggested that the effect of climate factors on the seasonal dynamics of influenza A in human was complicated.

Effects of the Minimum Temperature in Summer on the Hospital Emergency Room Visits for Cardiocerebrovascular Diseases,2004-2006 / 环境与健康杂志

Objective To explore the association between the minimum temperature in different seasons and the hospital emergency room visits for cardiocerebrovascular diseases(International Classification of Diseases,tenth vision ICD-10:I00-I99) in Beijing,China.Methods The data of the daily hospital emergency room visits for cardiocerebrovascular diseases(ICD-10:I00-I99)from one of Peking university hospitals,the data of relevant ambient air pollution from the Beijing Municipal Environmental Monitoring Center and the data of meteorological index from China meteorological data sharing service system between 2004— 2006 were collected The time-stratified case-crossover design was used to analyze the data.Results After adjusting SO2,NO2,and PM10,the results showed that each 1 ℃ increase in the daily minimum temperature in summer was associated with the intraday hospital emergency room visits(OR=1.039,P

Influence of Climate Factors and PM10 on Rotaviral Infection: A Seasonal Variation Study / 대한소아소화기영양학회지

PURPOSE: Recently, while the authors were experiencing that the epidemic period of rotaviral infection happened more in the early spring, we tried to find out how the outbreaks of rotaviral infection are changing in detail depending on the weather condition since it has something to do with the climate factors and PM10. METHODS: Fourteen hundreds seventy nine patients who were proved to be positive to rotavirus were chosen among children less than 5 years old from January 1995 to June 2003. Among various climate factors, monthly average temperature, humidity, rainfall and PM10 were selected. RESULTS: Rotaviral infection was most active in 2002 as 309 (20.9%) patients. It has been the spring that is the most active period of rotaviral infection since 2000. The temperature (RR=0.9423, CI= 0.933424~0.951163), rainfall (RR=1.0024, CI=1.001523~1.003228) and PM10 (RR=1.0123, CI= 1.009385~1.015248) were significantly associated with the monthly distribution of rotaviral infection. CONCLUSION: Through this study we determined that the epidemic period of rotaviral infection is changed to spring, which is different from the usual seasonal periods such as late fall or winter as reported in previous articles. As increased PM10 which could give serious influence to the human body, and changing pattern of climate factors such as monthly average temperature and rainfall have something to do with the rotaviral infection, we suppose that further study concerning this result is required in the aspects of epidemiology, biology and atmospheric science.