ObjectiveTo investigate the prevalence of norovirus in environment and population in coastal area and explore the virus transmission route.MethodsSamples of cultivated oysters, aquaculture water, and vomitus/faeces of patients with acute gastroenteritis were collected in Changsha Bay each month from December 2013 to December 2014. Noroviruses were detected by both real time RT-PCR and semi-nested RT-PCR. The partial capsid gene was amplified and sequenced by Sanger approach to conduct phylogenetic analysis. ResultsA total of 331 samples of cultivated oysters, 110 samples of aquaculture water and 75 samples of vomitus/faeces from diarrhea patients were detected. Norovirus positive rates were 32.6% (108/331), 11.8% (13/110), and 20.0%(15/75) in samples of cultivated oysters, aquaculture water, and diarrhea patients, respectively. Positive percentage of norovirus was higher in winter-spring season than that in summer-autumn season for the samples of oysters and aquaculture water (P<0.05 or P<0.01). Nine genotypes were detected in cultivated oysters, 5 in diarrhea patients, and 4 in aquaculture water. Identical genotypes were found in different samples. High sequence identities of norovirus were observed in the three types of samples (95.8%-99.7%).ConclusionNoroviruses prevailed and persisted in Changsha Bay with high genetic diversity. There would be a circulation route of noroviruses among the population and environment. It is necessary to control the contamination of norovirus in aquaculture water for shellfish food hygiene.

ObjectiveTo investigate the infection status of viral pathogens in patients with acute respiratory tract infection (ARTI) in Guangdong Province, so as to provide evidence for clinical diagnosis and treatment.MethodsDuring 2009 to 2011, one hospital was selected separately from cities of Guangzhou, Zhuhai, Zhanjiang, Shaoguan, and Shantou. Nasal swabs were collected from patients with ARTI for 1-3 days in the selected hospitals. Influenza and other respiratory viruses were tested by molecular assays simultaneously. Descriptive epidemiological method was used to analyze the epidemiological characteristics of various viral infections. ResultsA total of 1 234 samples were collected, of which 555 (45.0%) were positive for viral nucleic acid. The most virus detected was HRV (30.3%, 168/555), followed by FluA (26.1%，145/555). The detection rates were statistically significant between different age groups (P<0.01), and the highest detection rate was found in group aged at 0 to 4 years (62.1%, 185/298). The positive detections rates were 45.5% (326/716) for males and 44.2% (229/518) for females (P>0.05). Except HRV, other viral infections had obvious seasonal characteristics. The mixed infection was found in 27samples, with a mixed infection rate of 2.2%.ConclusionHRV and FluA were predominant viral pathogens in patients with ARTI in Guangdong Province, viral infections had obvious age and seasonal characteristics, and co-infections were detected in parts of ARTI patients.

ObjectiveTo investigate the covering status quo and influencing factors of the HIV/AIDS prevention services in peer education among men who have sex with men (MSM) . MethodsUsing snowball sampling method, MSM subjects were recruited to conduct self-administered anonymous behavior investigation and serological detection from April to October 2014 at a proper fixed location after informed consent in 9 counties (cities or districts) of Mianyang, Sichuan Province.ResultsA total of 1 097 MSM were investigated and their median age was 23 years. Among the participants, 569 cases（51.9%）had high school education level or below, 906 （82.6%） were unmarried. In the past one year, the coverage rate of peer education was 72.6% (796/1 097), the positive rate of anti-HIV was 3.8% (42/1 097), and the positive rate of syphilis was 5.9 % (41/733). The HIV infection rates were 2.4% (19/796) for MSM who received the peer education and 7.6% (23/301) for those who did not (P<0.01); the syphilis infection rates were 5.2%（29/554）and 6.7%（12/179）for the two groups of MSM, respectively (P>0.05). Unconditional logistic regression analysis showed that the possibility of accepted peer education for the participants whose domicile was other counties in this city or other areas in this province were 0.390 times or 0.420 times that for those whose domicile was in this counties/areas; the possibility of accepted peer education for the participants whose number of local MSM friends >10 was 4.591 times that for those whose number of local MSM friends ≤10; for the participants who sought sexual partners in other areas of this city/province was 2.719 times that of those who did it in the counties/areas where they were living; for the participants who sought sexual partners through the internet was 0.510 times that for those who did it through other ways; the participants who had anal sex ≥twice in the past one week was 2.280 times that for those who had anal sex less than once in the past one week; for the participants who had protected anal intercourse in the last 6 months was 4.228 times that for those who did not; and for the participants whose HIV test was positive was 0.186 time that for those whose HIV test was negative (all P<0.05). ConclusionThe coverage rate of MSM peer education was imbalanced in different areas. Peer education promoted awareness of HIV/AIDS knowledge and safe sex behavior effectively, reduced the risk of HIV infection, and should be strengthened.

ObjectiveTo assess the reliability and validity of the Sub-health Measurement Scale Version 1.0 (SHMS V1.0) for measuring the sub-health status of new-generation migrant workers in the Pearl River Delta (PRD). MethodsA regional stratified sampling method was used to select the new-generation migrant workers in 7 prefecture-level cities in PRD. The survey contents included general information, lifestyle and experience events, SHMS V1.0, and the short form 36 health survey questionnaire (SF-36). Methods of sub reliability half reliability and internal consistency for reliability rating scale, construct validity, criterion validity, and responsiveness scale for validity assessment scale were used. ResultsA total of 1 500 questionnaires were distributed and 1 238 valid ones were recovered, with an effective response rate of 82.53%. Of the 1 238 responders, 530 (42.8%) were male, 807 (65.2%) were married, and 562 (45.4%) had educational level at junior middle school or below. The Cronbach's α coefficient of SHMS V1. 0 was 0.923 and the split-half reliability was 0.855. The scale of correlation coefficient of each dimension and the subscale was between 0.520 and 0.890, indicating the correlation was larger and the correlation coefficient of other subscale was smaller. Extracted 7 principal components by varimax rotation method, the cumulative contribution rate was 63.576%. Each entry had higher load value on one factor (between 0.588 and 0.886), but had lower load value on the other 6 factors. The correlation coefficient between total score of SHMS V1. 0 and total score of SF-36 was 0.750 (P＜0.01). The ceiling/floor effect revealed high sensitive that top score percentage of physiological, psychological, and social subscales in total scale was between 0.08 and 3.23 and lowest score proportion of each subscale in the total scale ranged from 0.08 to 0.72. The proportion of highest and lowest scores was small, suggesting that the responsiveness of the scale was sensitive. ConclusionSHMS V1.0 is a reliable, valid, and sensitive measurement scale for measuring the sub-health of the new-generation migrant workers in PRD.

ObjectiveTo investigate contents of plant growth regulator (PGR) residues in bean sprout sold in market in a city and to estimate the health risk of dietary PGR intake from bean sprout.MethodsUsing simple random sampling method, samples of soybean sprouts and mungbean sprouts were collected from farmers markets and supermarkets. Contents of 4-Chlorophenoxyaceticacid, 2,4-Dichlorophenoxyacetic acid, Naphthaleneacetic acid，Gibberellin，and indolebutyric acid in the samples were determined by high-performance liquid chromatography tandem mass spectrometry. The exposure risk to residents caused by the PGR s in bean sprouts was evaluated. ResultsA total of 78 samples were collected from farmers markets and supermarkets in the city, including 45 samples of soybean sprouts and 33 samples of mungbean sprouts. The average contents of 4-Chlorophenoxyaceticacid and 2,4-Dichlorophenoxyacetic acid were 0.097 and 0.004 mg/kg in the soybean sprouts, respectively. The average content of 4-Chlorophenoxyaceticacid was 0.026 mg/kg in the mung sprouts. The average exposure level of 4-Chlorophenoxyaceticacid and 2,4-Dichlorophenoxyacetic acid in soybean sprout were 6.2×10-5 and 2.5×10-6 mg/ (kg bw?d), accounting for 1.03% and 0.02% of the health guidance values. The high dietary exposure level of 4-Chlorophenoxyaceticacid and 2,4-Dichlorophenoxyacetic acid in soybean sprout were 2.0×10-4 and 8.3×10-6 mg/ (kg bw?d), accounting for 3.33% and 0.08% of the health guidance values, respectively. The average dietary exposure level and high dietary exposure level of 4-Chlorophenoxyaceticacid in mung sprout were 1.6×10-5 and 3.6×10-5 mg/ (kg bw?d), accounting for 0.27% and 0.60% of the health guidance values, respectively. Naphthaleneacetic acid，Gibberellin，and indolebutyric acid were not detectable in the sprout samples.ConclusionPGRs 4-Chlorophenoxyaceticacid and 2,4-Dichlorophenoxyacetic acid could be detected in bean sprouts purchased in the markets in a city. The dietary exposure levels in the city residents are far below the health guidance values, indicating that dietary exposure to the five PGRs in bean sprout could not pose a health risk to the residents.

ObjectiveTo analyze the effectiveness of varicella vaccine in varicella outbreaks, so as to provide scientific basis for varicella control and the adjustment of immunization strategy. MethodsFour schools in Guangdong Province which experienced varicella outbreaks were selected as study fields. Students who had not previously had varicella were selected from classes with high morbidity of varicella as study subjects. Data on inoculation history of varicella vaccine and varicella occurrence were collected from the subjects. Retrospective cohort study was used to analyze the relationship between the inoculation history of varicella vaccine and attack rates of varicella during the outbreak, and the effectiveness of varicella vaccine was then calculated. ResultsAmong the subjects attack rates of varicella were 28.3% (53/187), 32.9% (24/73), 31.9% (37/116), and 36.4% (36/99), respectively, in four schools with outbreaks of varicella. The inoculation rates of varicella vaccine were 27.3% (51/187), 78.1% (57/73), 87.1% (101/116), and 49.5% (49/95), respectively. Among the subjects vaccinated with 1 dose of varicella vaccine in the four schools, the relative risks developing varicella were 0.52, 0.69, 0.50, and 0.39, respectively; the effectiveness of varicella vaccine was 48%, 31%, 50%, and 61% for students vaccinated with 1 dose of varicella vaccine, but 100% for those vaccinated with 2 doses.ConclusionIn the population with high exposure to varicella, one dose of vaccine is not enough for varicella prevention. Inoculation schedule of varicella vaccine should be adjusted from one dose to two doses among students to reduce the varicella outbreaks effectively.

ObjectiveTo analyze the epidemiological characteristics and trends of varicella in Yunfu City, so as to provide scientific basis for the development of the prevention and control measures.MethodsDescriptive epidemiological method was adopted to analyze the incidence data of varicella in Yunfu during 2012-2014.ResultsA total of 1 169 varicella cases were reported during this period and the average annual incidence was 16.25/100 000. The incidence peaks were observed during May-August and November-January, accounted for 32.76% (383/1 169) and 42.60% (498/1 169) of total cases, respectively. The top three areas with the most reported cases were Yuncheng District (451 cases), Yun'an District (297 cases), and Yu'nan County (292 cases). The cases were mainly the children aged below 15 years, accounted for 89.14% of the total cases (1 042/1 169). Of all the cases, 698 were male and 471 were female, with a male to female ratio of 1.48∶1. The occupational distributions of varicella cases were mainly the schoolchildren (38.32% of the total cases), followed by the scattered children (33.02%) and the children in child care settings (21.47%). The average varicella vaccine coverage was 1.44% in Yunfu City during 2012-2014. Vaccination coverage was highest for Yu'nan County (1.93%). Differences in vaccination coverage rates were statistically significant between different areas (P<0.01).ConclusionThe incidence of varicella presented a rising trend and double peaks in spring-summer and winter in Yunfu City during 2012-2014, and the varicella vaccination coverage rates varied in different areas. The varicella vaccination should be strengthened among the young children to control the incidence of varicella in the future.

ObjectiveTo analyze the epidemiological characteristics of varicella in Maonan District, Maoming City during 2008-2010, to provide the basis for developing prevention and control strategies. MethodsEpidemic data of varicella in Maonan District during 2005-2014 were collected from the China information system for disease prevention and control and then analyzed using descriptive epidemiological methods.ResultsA total of 912 cases of chicken pox were reported in Maonan District from 2005 to 2014 and the average annual incidence rate was 11.18/100 000. Two peaks in the incidence of varicella were observed, the first from April to June (264 cases) and the second from December to January (305 cases), accounting for 28.95% and 33.44% of the total cases, respectively. The top five towns or street offices with the most reported cases (724 cases) were Hedong, Guandu, Hexi, Gongguan, and Zhanqian, accounting for 79.39% of the total cases. The cases were mainly the children aged 1-10 years (722 cases), accounting for 79.17% of the total cases. Of all the cases, 556 were male and 356 were female, with a male to female ratio of 1.56∶1. Cases were mainly the school children (392 cases), followed by the children in child care settings (237 cases) and scattered children (192 cases), accounting for 42.98%, 25.99%, and 21.05% of the total cases, respectively. Six outbreaks of varicella were reported in Maonan District during 2005-2014, with a total of 123 cases, mainly occurred in the kindergartens and primary schools.ConclusionThe outbreaks of varicella showed a rising trend in Maonan District in recent years and the children aged 1-10 years were the high-risk group. Henceforth, the vaccination program of varicella should be expanded to reduce the incidence of varicella.

ObjectiveTo analyze the epidemiological characteristics of varicella in Shixing County so as to provide scientific basis for varicella vaccination and epidemic control.MethodsDescriptive epidemiological method was used to analyze the varicella epidemic data in Shixing County from 2011 to 2014.ResultsA total of 414 cases of varicella were reported from 2011 to 2014, with an average annual incidence of 42.30/100 000. The incidence of varicella showed 2 peaks. The first peak was during May to June when 134 cases were reported, accounted for 32.37% of the total cases. The other peak was during November to January of next year when 132 cases were reported, accounted for 31.88% of the total cases. The cases were mainly concentrated in the children aged 1-6 years (251 cases, 60.63% of the total cases).Of all the cases, 249 were male and 165 were female, and the male to female ratio was 1.5∶1. The occupations of the cases were mainly the students (33.09% of the total cases), followed by the children in kindergartens and nurseries (31.64%) and scattered children (28.26%). ConclusionThe children aged under 7 years was the high-risk group of the varicella in Shixing County. The vaccination of varicella should be promoted based on voluntary participation and informed consent.

ObjectiveTo analyze the epidemiological characteristics of varicella outbreaks in Meizhou City, so as to provide scientific basis for effective control of varicella outbreaks.MethodsDescriptive epidemiological method was used to analyze varicella outbreaks in Meizhou City from 2009 to 2015.ResultsSeven outbreaks of varicella involving 158 cases were occurred in Meizhou City from 2009 to 2015. The attack rates were 0.46%-6.36%．Of 7 outbreaks, 5 occurred in primary schools and 2 in kindergartens. Outbreaks mainly occurred in April (4 outbreaks) and November（2 outbreaks）．Of all the cases, 91 were male and 67 were female; the male to female ratio was 1.36∶1．Most（82.28%）of the patients ranged in age from 6 to 11 years. Of 158 cases, 33 (20.89%) had clear immunization history.ConclusionThe primary schools are the highly occurring places of varicella outbreaks in Meizhou City and the primary school students are the key population in the occurrence of varicella. Targeted measures should be taken to strengthen the varicella prevention and control for the key population in the key place.