Epidemiological characteristics of injury caused by fall in the elderly aged ≥60 years in Guang- zhou in 2014-2018 / 中华疾病控制杂志

@#Objective To explore the epidemiological characteristics and influencing factors of fall of elderly aged ≥ 60 years in Guangzhou from 2014 to 2018 ，so as to provide evidence for effective prevention and control measures． Methods Data on fall of the elderly was collected from the first diagno- sis in injury surveillance hospitals in Guangzhou from 2014 to 2018，and distribution description and epi- demiological analysis were adopted． Ｒesults 9 503 cases of fall of the elderly were reported in 5 injury surveillance hospitals，accounting for 49．41% of injuries in the elderly，and had occupied the first place in the cause of injury in 5 consecutive years． The sex ratio of men to women was 1 ∶ 1．67． Most of the patients had a primary or junior school degree，high rate in October-December，mainly occurred at home when doing leisure activities or life activities． The fall mainly led to injuries of head or lower extremities， contributed to contusion /bruise or fracture． And most of them were mild and moderate injury． Logistic re- gression showed that female，old age，high educational level，December to February，at home，walking， leisure activities and life activities were risk factors for falling among the elderly in Guangzhou ( all P ＜ 0．001) ． Conclusions Fall is the primary cause of injuries to the elderly in Guangzhou，especially the elderly female population． The targeted prevention and intervention measures should be developed ac- cording to their distribution characteristics．

Incidence trends and age distribution of colorectal cancer by subsite in Guangzhou, 2000-2011 / 癌症

<p><b>INTRODUCTION</b>Colorectal cancer (CRC) is the third most common cancer in China. The incidence of CRC has been increasing in recent years. The aim of this study was to explore the incidence trends and the age distribution of CRC by subsite in Guangzhou between 2000 and 2011.</p><p><b>METHODS</b>A total of 22,432 incident cases of CRC between 2000 and 2011 from Guangzhou Cancer Registry were identified. Crude incidence and age-standardized rates (ASRs), using the Segi's world standard population, were calculated for CRC and CRC subsites. The incidence trend was analyzed and the annual percentage change (APC) in incidence was calculated by using JoinPoint software.</p><p><b>RESULTS</b>The crude incidence increased significantly from 23.4/10(5) in 2000 to 37.4/10(5) in 2011 for males and from 20.9/10(5) to 30.5/10(5) for females. The ASRs of CRC incidence stabilized during the period of 2000-2011 for both males and females. The ages at the onset of CRC for both males and females during 2010-2011 were significantly higher compared with those during 2000-2002 (males: t = 1.95, P = 0.05; females: t = 6.03, P < 0.01). For males aged 50-64 years, the CRC incidence increased by 8.50% annually (P = 0.04) during 2000-2004 and by 1.68% annually (P = 0.03) during 2005-2011. For females aged 65 years and older, the CRC incidence increased by 5.77% annually (P = 0.03) during 2000-2004. There were no significant changes for the CRC incidences in males aged 49 and younger and 65 years and older and females aged 64 years and younger during 2000-2004, or for those in all females as well as males aged 49 years and younger and 65 years and older during 2005-2011. The percentage of colon cancer in all CRCs increased significantly for both males and females between the periods of 2000-2002 and 2010-2011. The ASRs of descending colon and sigmoid colon cancer incidences increased significantly for females during 2005-2011 (APC, 5.51% and 1.08%, respectively, both P < 0.05).</p><p><b>CONCLUSIONS</b>The crude incidence of CRC increased significantly between 2000 and 2011 because of the aging, whereas the ASRs kept stable. The percentage of colon cancer in all CRCs increased significantly. Further surveillance, research, and intervention are needed to identify the causes of these changes and to reduce the incidence and mortality of CRC.</p>

The Impacts of Mosquito Density and Meteorological Factors on Dengue Fever Epidemics in Guangzhou, China, 2006-2014: a Time-series Analysis / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To explore the associations between the monthly number of dengue fever(DF) cases and possible risk factors in Guangzhou, a subtropical city of China.</p><p><b>METHODS</b>The monthly number of DF cases, Breteau Index (BI), and meteorological measures during 2006-2014 recorded in Guangzhou, China, were assessed. A negative binomial regression model was used to evaluate the relationships between BI, meteorological factors, and the monthly number of DF cases.</p><p><b>RESULTS</b>A total of 39,697 DF cases were detected in Guangzhou during the study period. DF incidence presented an obvious seasonal pattern, with most cases occurring from June to November. The current month's BI, average temperature (Tave), previous month's minimum temperature (Tmin), and Tave were positively associated with DF incidence. A threshold of 18.25 °C was found in the relationship between the current month's Tmin and DF incidence.</p><p><b>CONCLUSION</b>Mosquito density, Tave, and Tmin play a critical role in DF transmission in Guangzhou. These findings could be useful in the development of a DF early warning system and assist in effective control and prevention strategies in the DF epidemic.</p>

Impact of heat wave in 2005 on mortality in Guangzhou, China / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To assess the impact of the heat wave in 2005 on mortality among the residents in Guangzhou and to identify susceptible subpopulations in Guangzhou, China.</p><p><b>METHODS</b>The data of daily number of deaths and meteorological measures from 2003 to 2006 in Guangzhou were used in this study. Heat wave was defined as ⋝7 consecutive days with daily maximum temperature above 35.0 °C and daily mean temperature above the 97th percentile during the study period. The excess deaths and rate ratio (RR) of mortality in the case period compared with the reference period in the same summer were calculated.</p><p><b>RESULTS</b>During the study period, only one heat wave in 2005 was identified and the total number of excess deaths was 145 with an average of 12 deaths per day. The effect of the heat wave on non-accidental mortality (RR=1.23, 95% CI: 1.11-1.37) was found with statistically significant difference. Also, greater effects were observed for cardiovascular mortality (RR=1.34, 95% CI: 1.13-1.59) and respiratory mortality (RR=1.31, 95% CI: 1.02-1.69). Females, the elderly and people with lower socioeconomic status were at significantly higher risk of heat wave-associated mortality.</p><p><b>CONCLUSION</b>The 2005 heat wave had a substantial impact on mortality among the residents in Guangzhou, particularly among some susceptible subpopulations. The findings from the present study may provide scientific evidences to develop relevant public health policies and prevention measures aimed at reduction of preventable mortality from heat waves.</p>

A norovirus-borne outbreak caused by contaminated bottled spring water in a school, Zhejiang province / 中华流行病学杂志

Objective To study a local hospital reported acute gastroenteritis in a boarding school on its source of infection, mode of transmission and risk factors of the infection. Methods A suspected case was defined as who had developed diarrhea (≥3 times/day) or vomiting among teachers or students of the school, during April 19-30, 2010. A confirmed case was from a probable case plus tested positive for norovirus in stool specimens by using RT-PCR. Stool specimens of cases and environmental specimens were collected for laboratory diagnosis. In a ease-control study, we compared exposures to sources of bottled water, consumption of bottled water, and hygienic habits of 220 probable or confirmed cases from April 21-23 in the peak of the outbreak, together with another 220 controls, with frequency-matched by school grade. Results 20.3% of the 1536 students but none of the teachers developed the disease. 98.6% of the cases (n=217) and 85.5% (n=188) of the controls had drunk bottled water in the classroom (ORM-H= 12.3,95%CI: 3.7-40.9). 47.9% (n= 104)of the cases and 41.5% (n=78)of the controls had drunk unboiled bottled water in classroom (ORM-H=3.8,95%CI: 1.5-9.6). 47.9% (n=104) of the cases and 48.4% (n=91) of the controls had drunk bottled mixed water (boiled and unboiled) in the classroom (ORM-H=2.8, 95%CI: 1.1-7.0).Stool specimens from 3 cases and one bottle of uncovered bottled water in classroom showed positive of having norovirus genotype Ⅱ. Coliforms was cultured much higher rates than standard deviations in the bottled water. The factory making the bottled water was not licensed or having strict disinfection facilities. Conclusion Bottled spring water contaminated by norovirus was responsible for this outbreak.

An outbreak of measles among unvaccinated migrant population in Zhejiang province, from June to August, 2010 / 中华流行病学杂志

Objective On July 6, 2010, the parents of a patient with confirmed measles reported several suspected measles patients with fever and rash in their village. An investigation was carried out to verify and understand the cause of the outbreak. Methods Several suspected cases had an onset of fever and rash in this and other neighboring villages during June 1 to August 3,2010. A confirmed case was a suspected case with measles-specific IgM identified in the serum. We conducted door-to-door visits and searched the Chinese Center for Disease Control and Prevention Information System to identify cases, also conducted a retrospective cohort study among migrant children aged 8 months-14 years to identify risk factors related to measles. Results We identified 19 measles cases (17 confirmed case, 2 suspected cases)in the village, and all of them were migrants. Children aged 1-2 years had the highest attack rate(13%). The primary case-patient had onset on the day she arrived in this village(June 4,2010). Caretakers from an unlicensed private clinic were providing service in the village but did not report the outbreak to the public health authority. The outbreak was identified only after receiving a report from the parents of one of the patients, by that time the outbreak had lasted for one month. The measles vaccine coverage rate was 81% among the 315 migrant children aged 8 months-14 years. Among the 61 unvaccinated children, those who reportedly being contacted a measles patient had a higher attack rate(14/16, 88%)than those who did not(2/45, 4.4%)(Relative risk=20, Fisher' s exact 95% confidence interval: 5.7-94). Conclusion The low measles vaccine coverage among migrant children and lack of measures taken on the incident, timely isolation diagnosis/reporting by the caretakers from the unlicensed private clinic etc. had contributed to this prolonged outbreak. Measures need to be taken to improve the immunization services for migrant populations and to enhance measles surveillance programs in the area.

Investigation on a seasonal influenza accompanying with the first locale novel A/H1N1 influenza outbreak in China / 中华预防医学杂志

<p><b>OBJECTIVE</b>To timely summarize past experience and to provide more pertinent reference for control and prevention in A/H1N1 cases in influenza season.</p><p><b>METHODS</b>During May 25 to 31, 2009, 2 secondary community cases caused by a influenza A/H1N1 imported case. In the close contacts of 3 A/H1N1 cases, 14 had some aspirator symptoms onset, such as fever (> or = 37.5 degrees C), cough, sore throat and etc. Laboratory tests excluded the infection of A/H1N1 influenza. For throat swab test for the 14 cases, 7 were tested for seasonal influenza virus. A face-to-face or telephone interview was conducted by CDC staff to collect information of 62 close contacts.</p><p><b>RESULTS</b>Of 14 fever cases, there was no significant by differences by age[15-age group: 19.2% (5/26), over 25-age group: 25.0% (9/36); chi(2) = 0.287, P = 0.592]; by sex group [24.0% (6/25) for male and 21.6% (8/37) for female; chi(2) = 0.048, P = 0.826], by working units [dressing and design, photograph, saleroom and others, consumer group: 42.1% (8/19), 27.3% (3/11), 12.5% (2/16) and 6.3% (1/16); chi(2) = 7.653, P = 0.054], by dormitory style [dormitory style = 33.3% (4/12), non-dormitory style = 29.4% (10/34); chi(2) = 0.699, P = 0.403]. All the cases had fever (37.5 - 37.9 degrees C), no case had diarrhea. One in 3 A/H1N1 cases had diarrhea. All the 14 cases were negative result for A/H1N1 RNA. Six from 7 cases were positive for seasonal influenza test.</p><p><b>CONCLUSION</b>This was a seasonal influenza outbreak happened in the close contacts of first confirmed A/H1N1 cases in community in mainland China. It showed that we should exclude the seasonal influenza in the investigation of A/H1N1 cases in the seasonal influenza period in some time. It is necessary to take effective measure to strengthen the control and prevention of seasonal influenza.</p>

Epidemiological characteristic of first case of locally identified A/H1N1 secondary cases caused by imported source of infection in China / 中华流行病学杂志

Objective To study the first locally identifcd A/HINI secondary cases outbreak in China. Methods Interview and field investigation were integrated to describe the whole process of transmission on each case and to illustrate the relationships between the onset of the disease and the retated factors. Results Two contact persons appearanced fever and whose throat swabs were tested positive to H1N1 viral nucleic acid. The two had a history of contact in a short distance with the initial imported case without any protective measure in the poor air ventilation. The patients clinical situation was slight. The incubation was between 37 hours and 57 hours. No other new case was found after intervention as isolation and antisepsis were taken. Conclusion This event was proved to be an outbreak of local A/H1N1 secondary cases caused by the imported case. The main mode of transmission was personal contact in a short distance without protection, through air and droplet. The locus with poor air ventilation was high risk place. Contact persons should be observed seven days and tested continuously.Infectivity and pathogenicity of the A/H1N1 virus were limited and appeared weakened by generations. Patient's condition was related with persistence and frequency of contact with the infection sources. Enhancing management of contact persons, health education, early diagnose, early treatment and early insulation were effective measures of controling and prenventing the spread A/H1N1.

Application of pulse-field gel electrophoresis analysis in the source-tracking of cholera epidemics / 中华流行病学杂志

<p><b>OBJECTIVE</b>To apply pulse-field gel electrophoresis analysis(PFGE) in the analysis of cholera outbreak events and to determine the molecular epidemiological characteristics of Vibrio cholerae ( V. cholerae) isolates.</p><p><b>METHODS</b>PFGE using restriction enzyme Not I was employed in the molecular subtyping of forty-one strains of V. cholerae isolated in cholera outbreak events from 2003 to 2005 in Guangzhou area and PFGE patterns were analyzed by BioNumerics Version 4.0 software to perform cluster analysis. Pattern profiles were compared by utilizing of Dice coefficient and UPGMA(unweighted pair group method with arithmetic averages). Comparison of PFGE typing results was performed with phage-biological typing and pathogenicity-associated genes typing.</p><p><b>RESULTS</b>In cholera outbreak events, PFGE could discriminate epidemiologically related and unrelated strains, having more discriminatory power than phage-biological typing and pathogenicity-associated genes-typing.</p><p><b>CONCLUSIONS</b>Molecular sub-typing by PFGE could disclose the epidemiological relationships of strains from humans and the environment, providing molecular epidemiological evidence and support for the source-tracking of cholera outbreak events.</p>

Analysis of characteristics of major pathogenicity-related genes of Vibrio cholerae isolated in Guangzhou area from 2001 to 2005 / 中华预防医学杂志

<p><b>OBJECTIVE</b>To apply multiplex polymerase chain reaction (MPCR) assay and sequencing in study of the carrying status of four pathogenicity-related genes of Vibrio cholerae (V.cholerae) and the variation of ctxA.</p><p><b>METHODS</b>Primers targeting cholera toxin sub-unit A gene (ctxA), toxin-coregulated pilus gene (tcpA), accessory cholera enterotoxin gene (ace), zonula occludens toxin gene (zot) were designed and the MPCR method was applied to detect the pathogenicity-related genes of 276 strains of V.cholerae isolates. The amplified fragments of ctxA gene were sequenced and the genetic homology of the amplified fragments of ctxA was analyzed.</p><p><b>RESULTS</b>Of the 276 strains of V.cholerae, 93.9% strains from human sources belong to the pathogenicity-related genes type A (ctxA(+)tcpA(+)ace(+)zot(+) type) and 6.1% belong to pathogenicity-related genes type C (ctxA(-)tcpA(-)ace(-)zot(-) type). Type A strains from clinical sources were isolated from patients with mild to severe symptom and carriers, among which 68.5% were isolated from patients with mild symptom and 21.9% from carriers. All 63.6% of type C strains from clinical sources were isolated from patients with mild symptom and 36.4% from carriers. The proportion of type C strains that caused mild symptom was higher than that of type A strains. Of the 78 strains isolated from the environment, 9.0% strains belong to pathogenicity-related type A and 35.9% belong to the pathogenicity-related genes type B (ctxA(-)tcpA(-)ace(+)zot(+) type), while 55.1% belong to pathogenicity-related genes type C. The sequencing results showed little genetic variation among the amplified fragments for ctxA.</p><p><b>CONCLUSION</b>MPCR disclosed the polymorphic status of pathogenicity-related gene patterns in V.cholerae isolates of Guangzhou, providing effective means for further study on evolution of pathogenicity-related genes among V.cholerae isolates from human and environmental sources. This study also offers significant guidance for effective prevention, control and warning against cholera epidemic in local area.</p>