Assessment of Individual and Mixed Effects of Six Minerals on Thyroid Hormones in Chinese Pregnant Women.

The biosynthesis of thyroid hormones is essential for brain and neurological development. It requires iodine as a key component but is also influenced by other nutrients. Evidence for the combined nutrient status in relation to thyroid hormones during pregnancy is limited. We aimed to investigate the joint associations of iodine, selenium, zinc, calcium, magnesium and iron with maternal thyroid functions in 489 pregnant women from Hangzhou, China. Serum levels of six essential minerals and thyroid function parameters were measured during the first antenatal visit. Linear regression, quantile g-computation and Bayesian kernel machine regression were used to explore the individual and joint relationships between the six minerals and thyroid hormones. Linear regression analyses revealed that calcium was positively associated with free triiodothyronine (FT3). Zinc was positively associated with free thyroxine (FT4). Iodine was negatively associated with thyroid-stimulating hormone (TSH) and positively associated with FT3 and FT4. The quantile g-computation and BKMR models indicated that the joint nutrient concentration was negatively associated with TSH and positively associated with FT3 and FT4. Among the six minerals, iodine contributed most to thyroid function. The findings suggested that maintaining the appropriate concentration of minerals, either as individuals or a mixture, is important for thyroid health during pregnancy.

Thyroglobulin as a Sensitive Biomarker of Iodine Status in Mildly and Moderately Iodine-Deficient Pregnant Women.

Pregnant women are more susceptible to iodine deficiency. However, there are limitations in existing indicators for the evaluation of iodine nutrition in pregnant women. The study aimed to explore whether thyroglobulin (Tg) can be used as a more sensitive biomarker for pregnant women with mild and moderate iodine deficiency. A repeated-measure study was conducted among 1332 pregnant women in Zhejiang Province, China. Serum and urine specimens were collected at a mean of 10, 17, and 32 weeks of pregnancy, respectively; thyroid-stimulating hormone (TSH), Tg, and urinary iodine concentrations were measured. Linear mixed effects models were used to determine the associations between interaction of iodine concentrations and increasing gestation week and TSH and Tg, where participants were divided by urinary iodine concentration (UIC). The median Tg concentration was 11.56, 11.45, and 12.43 µg/L in the first, second, and third trimesters, respectively. After controlling the covariates, the interaction effects between the iodine status and gestation week were significant for both TSH and Tg (p = 0.038 and p = 0.007, respectively). TSH increased with the week of gestation in both iodine concentration groups. Tg increased with advancing pregnancy in the iodine-deficient group whereas it did not in the iodine-sufficient group. There was no significant variation in TSH at each trimester, and Tg was higher in the iodine-deficient group than in the iodine-sufficient group. Tg may be a more sensitive iodine status biomarker than TSH for pregnant women with mild-to-moderate iodine insufficiency.

Study on influential factors and reference values for thyroid volume in Chinese children aged 6-12 years.

The purpose of the current study was to research the factors influencing thyroid volume (TVOL) in 6-12-year-old children and update the reference values. A cross-sectional study was carried out in iodine-sufficient areas of four provinces in China. Urine, edible salt and drinking water samples were collected from children. Children's height, weight and TVOL were measured. Ridge regression was used to screen variables for solving the multicollinearity problem. Quantile regression was used to analyse the relationship between the quantiles of TVOL and other variables. In total, 5653 children aged 6-12 years were enrolled in this study, including 2838 boys and 2815 girls. There was no significant difference in TVOL between boys and girls (P > 0·05). Spearman correlation analysis showed that total TVOL was positively correlated with age, height, weight, body surface area (BSA) and BMI, and the correlation coefficients were 0·616, 0·663, 0·669, 0·685 and 0·479, respectively. Among them, the correlation between TVOL and BSA was the strongest. According to the ridge regression results, age and BSA influenced TVOL, and the ridge regression coefficients were 0·13 and 0·94, respectively. Quantile regression further showed that age and BSA had significant influences on the whole TVOL distribution (P < 0·001). Therefore, the TVOL of children aged 6-12 years in China was mainly influenced by age and BSA, and reference values for TVOL of different genders based on age and BSA were established.

The effects of temperature variability on mortality in patients with chronic obstructive pulmonary disease: a time-series analysis in Hangzhou, China.

Chronic obstructive pulmonary disease (COPD) is a leading cause of death in people aged over 60 years old. Research has been reported that ambient temperature and diurnal temperature range (DTR), as representative indices of temperature variability, are contributors to the development and exacerbation of COPD. However, few studies are available in Chinese population. In this study, we aimed to assess the associations of temperature variability on COPD mortality in a fast developing city in China. Using the mortality surveillance system, we obtained a total of 7,863 deaths attributed to COPD from 2014 to 2016. Quasi-Poisson generalized linear regression with distributed lag non-linear model was applied to explore the associations between temperature variability and COPD deaths, after controlling for the potential confounders, including relative humidity, day of week, public holiday, and long-term trend. A J-shaped association of DTR and a reversely J-shaped association of temperature for COPD mortality were observed. Risk estimates showed that the relative risks (RRs) of COPD mortality with extreme high DTR at lag 0 and 0-7 days were 1.045 (95% CI: 0.949-1.151) and 1.460 (95% CI: 1.118-1.908), and the extreme high temperature at lag 0 and 0-7 days were 1.090 (95% CI: 0.945-1.256) and 1.352 (95% CI: 1.163-1.572). Our findings suggest that short-term exposure to extreme temperature was associated with mortality for COPD in Hangzhou. The evidence has implications for policy decision-making and targeted interventions.

Low Iodine Intake May Decrease Women's Fecundity: A Population-Based Cross-Sectional Study.

Salt iodization is one of the most cost-effective strategies to eliminate iodine deficiency disorders (IDD). However, China's dismantling of salt monopoly has reduced the availability of iodized salt in the susceptible population in pregnancy, which might cause IDD and have adverse health effects on both themselves and their offspring. The aim of our study was therefore to explore the association between IDD and women's reproductive health. This is a population-based cross-sectional study conducted in 2018 in Zhejiang Province, China. A total of 1653 pregnant women participated in this study. Median urinary iodine concentration (UIC) in the population was used to assess iodine intake. Cox regression analyses were used to estimate the association between iodine intake and time to pregnancy, which was indicated with fecundability ratio (FR) and 95% confidence interval (CI). The percentage of participants with iodine deficiency who had been waiting longer than 13 months to get pregnant (20%; median UIC 119.6 µg/L) was significantly higher than those with iodine sufficiency (14%; median UIC 147.1 µg/L). A significant decrease in fecundity was observed in participants with iodine deficiency (FR, 0.820; 95% CI, 0.725-0.929) than those with iodine sufficiency. These findings indicate the importance of ongoing monitoring of iodine nutrition in women of reproductive age. Keeping a safe and optimal level of iodine nutrition during pregnancy should be emphasized.

Increasing mortality caused by chronic obstructive pulmonary disease (COPD) in relation with exposure to ambient fine particulate matters: an analysis in Southeastern China.

The objective of this study was to investigate the association between ambient particulate matters (PMs) and chronic obstructive pulmonary disease (COPD) mortality. generalized additive mixed model was employed to investigate the effects of ambient fine and coarse PMs on COPD mortality using 13,066 deaths from 2014 to 2016 among six cities in Zhejiang Province in Southeastern China. The daily average death count due to COPD was 3, varying from 1 to 7 among six cities. The daily 24-h mean concentrations were diverse among cities, from 29.7 to 56.8 µg/m3 for PM2.5, 16.7 to 30.3 µg/m3 for PM2.5-10, and 50.3 to 87.1 µg/m3 for PM10, respectively. The analysis showed that daily exposure to PM2.5 and PM10 was associated with increased mortality due to COPD and that weak effects were observed between PM2.5-10 and COPD mortality. Our results provided solid evidence that the fine particles in air pollution have stronger functions on adverse health effects other than coarser particles in Southeastern China, which may be considered as a potential clinic target in PM-associated COPD.

Geographical influences on thyroid abnormalities in adult population from iodine-replete regions: a cross-sectional study.

The studies on the increasing incidence of thyroid abnormalities are scarce. The aim of this current study was to ascertain the effects of geographical region on thyroid abnormalities under the context of universal salt iodization (USI). We randomly selected 1255 participants residing in inland and 1248 in coast, with the determination of urinary iodine concentration (UIC) and functional and morphological abnormalities of thyroid gland. The median UIC was significantly higher for the inland participants (188.5 µg/L) than the coastal participants (128.5 µg/L; p < 0.001), indicating iodine sufficiency in both populations according to the recommended assessment criteria by the World Health Organization. However, the spectrum of thyroid abnormalities varied between regions, with hypothyroidism prevalent in inland and thyroid nodules in coast. The associations between region and thyroid abnormalities via binary logistic regression models showed that the coastal participants were at a higher risk of total thyroid abnormalities than those from the inland (OR 1.216, 95% CI 1.020-1.449), after the adjustment of ten confounders (demographical characteristics, smoking status, metabolism syndrome, and hyperuricemia). These results indicated that further investigations of the adverse effects of hypothyroidism and thyroid nodules on health burden is urgently needed to sustain USI program.

The Effect of Iodine Status on the Risk of Thyroid Nodules: A Cross-Sectional Study in Zhejiang, China.

OBJECTIVE: The aim of this study was to explore whether iodine nutrition is associated with the risk of thyroid nodules among adult population in Zhejiang Province, China. METHODS: A cross-sectional study was conducted in the general population aged 18 years or older. A total of 2,710 subjects received physical examination, questionnaires, and thyroid ultrasonography. Urinary iodine concentration (UIC) and thyroid hormone levels were measured and documented for each subject. 4 multiple logistic regression models adjusted for other risk factors were applied to analyze the association between iodine nutrition and thyroid nodules. RESULTS: The prevalence of thyroid nodules was 15.5% among all adults. As indicated by all 4 models, subjects with UIC varying from 200 µg l-1 to 399 µg l-1 had lower risk of thyroid nodules compared with those with relatively low UIC (<100 µg l-1), with approximately 37-57 percent reduction in risk. Moreover, subjects with UIC between 100 and 199 µg l-1 had a decreased risk of thyroid nodules in model 1 and 2 (OR = 0.75, 95% CI, 0.58-0.97; OR = 0.75, 95% CI, 0.58-0.97, respectively). However, there was no significant difference of risk in thyroid nodules between subjects with high UIC (≥400 µg l-1) and low UIC (<100 µg l-1). Furthermore, intake of iodized salt was inversely associated with risk of thyroid nodules, with approximately 69-77 percent reduction in risk. CONCLUSION: The relationship between UIC and the risk of thyroid nodules is U-shaped. Consumption of noniodized salt is an independent risk factor of thyroid nodules.

Geographical influences on the iodine status in pregnant women, neonates, and school-age children in China.

BACKGROUND: Pregnant women, neonates, and school-age children are vulnerable to iodine deficiency. The iodine contents in the environment (drinking water and household salt for cooking) vary by geographical location in China. The aim of this study was to assess the iodine status in vulnerable groups from different geographical zones and analyze the iodine content in household salt and drinking water from these zones. METHODS: In coastal and inland regions of Zhejiang Province, China, samples of spot urine, drinking water, and household salt for cooking from both pregnant women and school-age children were determined for iodine concentration between 2017 and 2018. Thyroid-stimulating hormone (TSH) levels from neonates born between 2014 and 2015 were acquired from the Newborns Screening Information System. The iodine status of the vulnerable populations was assessed according to the criteria recommended by the World Health Organization. RESULTS: The median UIC of pregnant women was significantly lower in the coastal region (113.0 µg/L) than the inland region (134.9 µg/L; p < 0.001). The median UICs of pregnant women from these two regions were below the lower optimal iodine cutoff level of 150 µg/L. The percentage of neonates with elevated TSH (> 5 mIU/L) was significantly higher in the coastal region (15.8%) than the inland region (10.5%; p < 0.001). The percentage of neonates with elevated TSH from each region decreased within the range of mild iodine deficiency of 3-19.9%. The median UIC of the coastal school-age children was 156.0 µg/L, and the median UIC of inland children was 181.5 µg/L. Both medians fell within the recommended optimal iodine range of 100-299 µg/L. The iodine concentrations in drinking water varied from 1.0 µg/L in the inland region to 2.0 µg/L in the coastal region. The proportion of households that consumed iodized salt was lower in the coastal region (nearly 65%) than the inland region (approximately 95%). CONCLUSIONS: In these two regions with low iodine contents in drinking water, both pregnant women and neonates were iodine-deficient, although school-age children were iodine-sufficient. Urgent efforts are needed to improve the iodine status of pregnant women and neonates.

Characterization and health risk assessment of PM2.5-bound polycyclic aromatic hydrocarbons in 5 urban cities of Zhejiang Province, China.

In 2015, we measured polycyclic aromatic hydrocarbons (PAHs) in atmospheric fine particulate matter (PM2.5) collected from 5 cities in Zhejiang Province. The mean toxic equivalent quotient (TEQ) values of benzo(a)pyrene (BaP) ranged between 1.2-3.1 ng/m3. The BaP-TEQ displayed seasonal trends, such that winter > spring and autumn > summer. During the winter, the most abundant individual PAHs were 4-6ring PAHs (84.04-91.65%). The median daily intake of atmospheric PAHs ranged between 2.0-7.4 ng/day for all populations, with seasonal trends identical to that of BaP-TEQ. The 95th incremental lifetime cancer risk (ILCR) values induced by PM2.5-bound PAHs were far lower than 10-6 for all populations. The data suggested that the pollution levels in the 5 Zhejiang Province cities were higher than the Chinese National Ambient Air Quality Standard (NAAQS). In the future, relevant measures should be taken to control atmospheric PAHs, especially 4-6 ring PAHs. The data also revealed no obvious cancer risk for populations residing in these 5 cities of Zhejiang Province.

Poor Iodine Knowledge, Coastal Region, and Non-Iodized Salt Consumption Linked to Low Urinary Iodine Excretion in Zhejiang Pregnant Women.

BACKGROUND: Iodine deficiency in pregnant women, defined as a median urinary iodine concentration (UIC) of less than 150 µg/L, is an important public health issue. To improve their iodine intake, it is important to understand the knowledge and practices regarding iodine. METHODS: A cross-sectional investigation was conducted on 2642 pregnant women during 2016⁻2017 in Zhejiang province, China. A 3-point Likert scale questionnaire was used to record knowledge. The UIC and iodine content in household salt were determined. RESULTS: Coastal participants were iodine deficient (median UIC 127.6 µg/L) while inland participants were iodine sufficient (median UIC 151.0 µg/L). The average knowledge scores were significantly lower for the coastal participants (24.2 points vs. 25 points for the inland participants; p < 0.001). The percentage for iodized salt consumption was significantly lower for the coastal participants (88.9% vs. 96.0% for those inland; p < 0.001). A generalized linear model analysis showed that non-iodized salt consumption, coastal region, and low knowledge scores were independently associated with a low UIC. CONCLUSIONS: Comprehensive interventional strategies are needed to develop to achieve an optimal iodine status. We recommend that coastal pregnant women should take iodine supplements based on the consumption of iodized salt, and improvement of iodine-related knowledge.

Iodine deficiency in pregnant women after the adoption of the new provincial standard for salt iodization in Zhejiang Province, China.

BACKGROUND: Zhejiang has achieved the goal of elimination of iodine deficiency disorders (IDD) via the implementation of universal salt iodization (USI) since 2011. Iodine content in household table salt decreased from the national standard (35 ppm) to the Zhejiang provincial standard (25 ppm) in 2012. It is crucial to periodically monitor iodine status in pregnant women because IDD in pregnancy have adverse effects on fetal neurodevelopment. METHODS: We carried out a cross-sectional study between April 2014 and September 2015 in the eight sentinel surveillance counties across Zhejiang Province, where IDD was previously known to be endemic. A total of 1304 pregnant women participated and provided a random spot urine sample and a household table salt sample. Urinary iodine concentration (UIC) was determined using arsenic-cerium catalytic spectrophotometry. Iodine content in salt was measured using a titration method with sodium thiosulphate. RESULTS: Overall, the median UIC of the total study population of pregnant women was 129.3 µg/L, with a higher UIC in inland (152.54 µg/L) and a lower UIC in coastal counties (107.54 µg/L). Household coverage of iodized salt was 94.6% and the rate of adequately iodized salt was 89.9%. CONCLUSIONS: Our results indicate deficient iodine status in the pregnant population of Zhejiang, according to the lower cut-off value of optimal iodine nutrition (150 µg/L) recommended by the World Health Organization. In addition to sustaining USI, more efforts are urgently needed to improve iodine intake in women during pregnancy, especially those residing in the coastal counties.

Iodine Deficiency in Zhejiang Pregnant Women in the Context of Universal Salt Iodization Programme.

Zhejiang introduced universal salt iodization (USI) programme in 1995 and has achieved the goal of elimination of iodine deficiency disorders (IDD) since 2011. However, no systematical data of iodine nutritional status in population in pregnancy is available. In this cross-sectional study, pregnant women were interviewed to complete questionnaires in addition to handing in samples of urine and household table salt between March 2016 to February 2017. Date of birth, age of pregnancy, ethnicity and dietary iodine habits were recorded. The overall median urinary iodine concentration in 8561 pregnant women was 130.47 µg/L, which was lower than the cut-off value of iodine sufficiency of 150 µg/L recommended by the WHO. Participants using non-iodized salt, taking non-iodine-containing supplements, in coastal and in Han group were independently associated with iodine deficiency. The current USI programme did not supply Zhejiang pregnant women with sufficient iodine intake. They are generally iodine deficient, which have great public health importance since even mild IDD in pregnancy have adverse effects on fetal neurodevelopment. We strongly recommend urgent measures to improve iodine intake in pregnancy.

Acute effects of air pollution on respiratory disease mortalities and outpatients in Southeastern China.

The objective of this study was to investigate the potential association between air pollutants and respiratory diseases (RDs). Generalized additive models were used to analyze the effect of air pollutants on mortalities or outpatient visits. The average concentrations of air pollutants in Hangzhou (HZ) were 1.6-2.8 times higher than those in Zhoushan (ZS), except for O3. In a single pollutant model, the increased concentrations of PM2.5, NO2, and SO2 were strongly associated with deaths caused by RD in HZ, while PM2.5 and O3 were associated with deaths caused by RD in ZS. All air pollutants (PM2.5, NO2, SO2, and O3) were strongly associated with outpatient visits for RD in both HZ and ZS. In multiple pollutant models, a significant association was only observed between PM2.5 and the mortality rate of RD patients in both HZ and in ZS. Moreover, strong associations between SO2, NO2, and outpatient visits for RD were observed in HZ and ZS. This study has provided evidence that both the mortality rates and outpatient visits for RD were significantly associated with air pollutants. Furthermore, the results showed that different air pollutant levels lead to regional differences between mortality rates and outpatient visits.

An Increase in Consuming Adequately Iodized Salt May Not Be Enough to Rectify Iodine Deficiency in Pregnancy in an Iodine-Sufficient Area of China.

Universal salt iodization (USI) has been implemented for two decades in China. It is crucial to periodically monitor iodine status in the most vulnerable population, such as pregnant women. A cross-sectional study was carried out in an evidence-proved iodine-sufficient province to evaluate iodine intake in pregnancy. According to the WHO/UNICEF/ICCIDD recommendation criteria of adequate iodine intake in pregnancy (150-249 µg/L), the median urinary iodine concentration (UIC) of the total 8159 recruited pregnant women was 147.5 µg/L, which indicated pregnant women had iodine deficiency at the province level. Overall, 51.0% of the total study participants had iodine deficiency with a UIC < 150 µg/L and only 32.9% of them had adequate iodine. Participants living in coastal areas had iodine deficiency with a median UIC of 130.1 µg/L, while those in inland areas had marginally adequate iodine intake with a median UIC of 158.1 µg/L (p < 0.001). Among the total study participants, 450 pregnant women consuming non-iodized salt had mild-moderate iodine deficiency with a median UIC of 99.6 µg/L; 7363 pregnant women consuming adequately iodized salt had a lightly statistically higher median UIC of 151.9 µg/L, compared with the recommended adequate level by the WHO/UNICEF/ICCIDD (p < 0.001). Consuming adequately iodized salt seemed to lightly increase the median UIC level, but it may not be enough to correct iodine nutrition status to an optimum level as recommended by the WHO/UNICEF/ICCIDD. We therefore suggest that, besides strengthening USI policy, additional interventive measure may be needed to improve iodine intake in pregnancy.

[Effect factors of the prevalence of thyroid nodules in Zhejiang Province in 2010].

OBJECTIVE: To assess the prevalence of thyroid nodules and explore the risk factors for thyroid nodules among the community residents in Zhejiang Province. METHODS: The residents of twenty-two communities in Zhejiang Province were selectedwith stratified cluster sampling. The cross-sectional survey includes questionnaire, examination on thyroid. The prevalence and related factors of thyroid nodules was described, and the possible risk factors for thyroid nodules was analyzed with logistic regression. RESULTS: The prevalence of thyroid nodules in Zhejiang was 21. 78%, and the prevalence of a single nodule was 11. 75%, which was higher than that of multiple nodules( 10. 03%). The prevalence of thyroid nodules in men was less than women, urban residents higher than rural, and both increased gradually with age. The residents in coastal areas had the highest prevalence of thyroid nodules, followed by sub-coastal areas, inland minimum. High education level, consumption of seafood habits, high frequency of anger, the history of thyroid disease and iodine deficiency were potential risk factors for thyroid nodules in this surveyed population. CONCLUSION: The prevalence of thyroid nodules in Zhejiang Province was at the middle level, female prevalence was greater than male, and gradully increased with age, the elderly should be the focus of prevention. Although thyroid nodules of children was at the lower rate, it should be paid attention due to high risk to develop to malignancy. High education level, consumption of seafood habits, high frequency of anger, the history of thyroid disease and iodine deficiency were potential risk factors for thyroid nodules, which need to be confirmed by further epidemiologic study.

Larger Thyroid Volume and Adequate Iodine Nutrition in Chinese Schoolchildren: Local Normative Reference Values Compared with WHO/IGN.

Objective. Thyroid volume measured by ultrasound to define goiter needs reliable local thyroid volume reference from iodine-sufficient populations. The aim of this study is to explore the reference interval for normal thyroid volume in schoolchildren aged 8-10 years from Zhejiang Province, China. Methods. A probability-proportionate-to-size sampling method was applied to select a representative sample of 1213 children aged 8-10 years in Zhejiang Province to detect the thyroid volume, salt iodine, and urine iodine. Results. Median urinary iodine concentration in involved schoolchildren was 178.30 (125.00) µg l-1, with the percentage of samples less than 100 µg l-1 as 12.69% and more than 300 µg l-1 as 15.25%. Thyroid volume was significantly correlated with age and anthropometric measurements independently of each other. The 97th percentile of thyroid volume in our study was larger generally than the new international reference. Conclusions. The iodine nutritional status in Zhejiang Province was at an adequate level. Despite some limitations in this study, we initially established the reference values for thyroid volume in 8-10-year-old schoolchildren in Zhejiang Province, China, as a local reference to be used for monitoring iodine deficiency disorders.

Incidence of thyroid diseases in Zhejiang Province, China, after 15 years of salt iodization.

Thyroid diseases(TD) can be induced by either deficient or excessive iodine intake. Universal Salt Iodization(USI) program has been implemented in China since 1995, to prevent iodine deficiency disorders (IDD). To evaluate the current conditions of TD and the role of USI, a multi-stage stratified random sampling scheme was used to perform a cross-sectional survey on the incidence of TD among participants in 6600 households in Zhejiang Province, a coastal area in China. Iodine nutrition status of the population was assessed by dietary iodine intake recall and urinary iodine concentration (UIC) of the participants, and TD were diagnosed by thyroid ultrasonography for 15122 participants and for 5873 participants by serum criteria for thyroid function(fT3, fT4, TSH, TRAb, TgAb, TPOAb; see Introduction for abbreviations). The median UIC of the surveyed population was 163µg iodine/L. From the participants 23.2% had UIC<100µg/L which is moderately iodine-deficient according to WHO classification. Diffuse goiter was present in 2.3% of the population and thyroid nodule in 20.9%. The incidence of hyperthyroidism, subclinical hyperthyroidism, hypothyroidism, subclinical hypothyroidism, Graves' disease and chronic lymphocytic thyroiditis was 0.5%, 0.6%, 0.6%, 7.8%, 0.2% and 0.3%, respectively. The proportion of several TD for participants with non-iodized salt intake was higher than that for participants with iodized salt intake.

Epidemiologic Features of Enterovirus 71-Associated Hand-Foot-and-Mouth Disease from 2009 to 2013 in Zhejiang, China.

Enterovirus 71 (EV71) usually causes hand-foot-and-mouth disease (HFMD) with severe clinical symptoms and even deaths in China. There is no efficient antiviral drug to protect against severe EV71-associated HFMD, making the development of EV71 vaccines therefore a priority. However, the potential target subject population(s) to be immunized with EV71 vaccine are not well understood. In this study, we characterized the epidemiology regarding EV71-associated HFMD on the basis of provincial-level surveillance. We extracted data on EV71-associated HFMD from the National Notifiable Disease Reporting System in Zhejiang Province, China between 1 January 2009 and 31 December 2013 (n = 7650). The higher incidence rate of EV71 cases occurred in those children aged 12-23 months, with boys being predominant. Interestingly, different peaks activities of EV71 infection was observed in different calendar year, with one peak in 2009 and 2013 and two peaks in 2010-2012. However, EV71 infection seemed to predominately occur in warm season and a distinguished cyclic peak that seemed to be of about 12 months. Children aged 12-23 months are thus identified as an important target population for public health intervention, for example, it is recommended that these key subjects immunized with EV71 vaccine. In addition, an enhanced surveillance system for EV71-associated with HFMD needs to focus on generic and phylogenetic analysis.

Survey of iodine nutritional status in 2011, Zhejiang, China.

BACKGROUND: Universal salt iodization (USI) was introduced in China in 1995, but whether the iodine status is optimal is questionable. This study was conducted to assess the iodine nutrition among Zhejiang population in coastal regions in China. METHODS: A cross-sectional survey for iodine nutritional status was conducted with general population (n=10,350), including pregnant and lactating women (n=450 each) selected by stratified multistage sampling. Iodine content in drinking water, table salt and urine, were determined using arsenic-cerium catalytic spectrophotometry, the direct titration and the arsenic-cerium catalytic spectrophotometry, respectively, and daily iodine intake was estimated by 3 days of 24-hour recall method. RESULTS: The median iodine content in drinking water was 2.46 µg/L, Zhejiang belonged to the region of iodine deficiency in outer environment according to China standard. The median iodine content in table salt was 27.9 mg/kg, conforming to the standard requirements; the household coverage rate of qualified iodized salt reached 76.8%, which does not reach the standard requirement of WHO >90%. The dietary iodine intake of a reference individual averaged 379 µg/d, which indicated that the current iodine intake in diet was appropriate. In addition, the median urinary iodine concentration (UIC) was 162 µg/L in general population, and 130 µg/L in pregnant women, which didn't reach the standard requirements. CONCLUSION: The current dietary iodine intake in Zhejiang was generally sufficient and safe, but there is a risk of iodine deficiency among pregnant women and the population who do not consume iodized salt.