Objective:To investigate the importance of immunization in preventing measles infection and to determine the most useful laboratory tests for confirmation of measles.Methods:This study included pediatric cases evaluat...Objective:To investigate the importance of immunization in preventing measles infection and to determine the most useful laboratory tests for confirmation of measles.Methods:This study included pediatric cases evaluated with a presumed diagnosis of measles between December 2022 and June 2023,at Marmara University Pendik Training and Research Hospital.The effects of vaccination status and underlying disease on the clinical course,treatments,and complications were evaluated.Results:In total,117 patients were enrolled in the study with a median age of 80 months(IQR:32.5-125.0).Twelve patients with contact history were asymptomatic and had an underlying disorder,and intravenous immunoglobulin was given to them for post-exposure prophylaxis.Fifty-one patients had confirmed measles diagnosis.Ribavirin treatment was given to three patients(a newborn,a girl with rhabdomyosarcoma,and a healthy boy)with respiratory distress.Seventy-eight percent of confirmed measles cases were unvaccinated,and all hospitalized cases were unvaccinated or under-vaccinated.Four full-vaccinated children had confirmed measles infection.Measles PCR from nasopharyngeal swabs was negative in all of them,and their diagnosis was established with anti-measles IgM positivity.Conclusions:The measles vaccine is the most effective way to protect from measles and measles-related complications.Although measles can also occur in fully vaccinated patients,the disease is milder than in unvaccinated patients.Using ELISA and RT-PCR tests together may be beneficial in patients with high clinical suspicion for early diagnosis.展开更多
A sudden and unprecedented outbreak of molluscan Philine kinglipini occurred in summer 2022 in Jiaozhou Bay,Shandong,China,causing substantial damage to local mariculture industry of the Manila clam Ruditapes philippi...A sudden and unprecedented outbreak of molluscan Philine kinglipini occurred in summer 2022 in Jiaozhou Bay,Shandong,China,causing substantial damage to local mariculture industry of the Manila clam Ruditapes philippinarum.Although P.kinglipini has been found in many coastal regions of China,the molecular research of P.kinglipini has not been extensively studied,making it difficult to accurately identify and track P.kinglipini samples in field using molecular methods.Samples were collected during the outbreak and their morphological features and molecular sequences were analyzed.Results show that the causative species of the outbreak was P.kinglipini.The mitochondrial genome(mt DNA)of P.kinglipini was constructed for the first time,based on which phylogenetic analysis of the mt DNAs of P.kinglipini and related species in the order Cephalaspidea was carried out.As revealed by metabarcoding analysis of 18S rDNA V4,the seasonal change of P.kinglipini and closely related Philine species was striking with peaks between April and August.Therefore,metabarcoding analysis is applicable tool for monitoring the bloom development of P.kinglipini and related species.This study generated for the first time essential molecular marker sequences and mtDNA of P.kinglipini,which provided a reference for future characterization and monitoring of its outbreaks and for phylogenetic analysis of Philine species.展开更多
Mpox disease is caused by a double-stranded DNA virus, genus Orthopoxvirus of the family Poxviridae. The incubation period is usually 6 to 13 days but can range from 5 to 21 days while symptoms and signs may persist f...Mpox disease is caused by a double-stranded DNA virus, genus Orthopoxvirus of the family Poxviridae. The incubation period is usually 6 to 13 days but can range from 5 to 21 days while symptoms and signs may persist for 2 to 5 weeks. Although, the clinical features are usually less severe when compared to the deadly smallpox, the disease can be fatal with case fatality rate between 1% and 10%. In Imo State, Nigeria, there has been a changing epidemiology of the disease in the last 6 years and the frequency and geographic distribution of cases have progressively increased. This study aims to conduct a review of the disease epidemiology between 2017 and 2023 and implications for surveillance in Imo State. Surveillance data from the Surveillance Outbreak Response and Management System (SORMAS) was extracted between January 2017 and December 2023 across the 27 Local Government Areas (LGAs) of Imo State. A line list of 231 suspected cases was downloaded into an excel template and analyzed using SPSS<sup>®</sup> version 20 software. Analysis was done using descriptive statistics and associations were tested using Fischer’s exact at 0.05 level of significance. Of the 231 suspected cases, 57.1% (132) were males, 42.9% (99) were females and the modal age group was between the ages of 0 - 4 (32.5%). Eight (8) LGAs (districts) accounted for 71% (n = 164) of all the suspected cases. 21.2% (49) were confirmed positive, 27 males (55.1%) and 22 females (44.9%) (p > 0.05). Modal age group was 20 - 24 (22.4%, n = 11), 18% (9) were children under 14 years, p > 0.05. Case fatality rate was 8% (n = 4). There was no significant association between mortality and age group. Five (5) LGAs accounted for about 60% (29) of all confirmed cases. These LGAs contribute only 20% to the total population in the State. Only 5.6% and 4% of suspected and confirmed cases, respectively, had knowledge of contact with an infectious source. The study described the epidemiology of Mpox outbreaks between 2017 and 2023 and the findings have significant implications on detection and outbreak response activities.展开更多
Dengue fever(DF)has become a major public health concern in Nepal,with increasing outbreaks in recent years.Transmitted by Aedes mosquitoes,this climate-sensitive viral disease presents a significant challenge for hea...Dengue fever(DF)has become a major public health concern in Nepal,with increasing outbreaks in recent years.Transmitted by Aedes mosquitoes,this climate-sensitive viral disease presents a significant challenge for healthcare providers and policymakers.Since 2004,Nepal has experienced a sharp increase in DF cases,peaking in 2022 with 54784 cases and 88 deaths.The surge,driven mainly by serotypes 1,2,and 3,is exacerbated by climate change,which prolongs mosquito breeding seasons due to warmer temperatures and increased rainfall.This trend has even impacted previously unaffected hilly regions.Effective dengue control strategies must focus on climate change adaptation,strengthening healthcare system reinforcement,raising public awareness,and enhancing vector control measures.Government initiatives,like the national dengue control program,play a critical role,but research and community engagement are also vital for prevention and early detection.Integrating climate resilience into public health efforts is essential to reducing the dengue burden in Nepal.展开更多
Dengue fever,caused by the dengue virus(DENV),poses a significant public health challenge globally,with Nigeria experiencing sporadic outbreaks.A clear understanding of the dengue burden has not been achieved in Niger...Dengue fever,caused by the dengue virus(DENV),poses a significant public health challenge globally,with Nigeria experiencing sporadic outbreaks.A clear understanding of the dengue burden has not been achieved in Nigeria,just as in other African countries.Understanding the epidemiology and burden of dengue fever is essential for effective prevention and control strategies.This paper examines the recent dengue outbreaks in northern Nigeria,particularly in Sokoto state,and evaluates the recommended Takeda dengue vaccine(TDV)along with future prevention strategies.Despite limited surveillance and underreporting,dengue fever is endemic in Nigeria(with over 5 million cases and 5000 dengue-related deaths in 2023),with recent outbreaks indicating a growing concern.The TDV,a live attenuated tetravalent vaccine,has shown promise in preventing dengue fever,but challenges such as vaccine acceptance and access-ibility need to be addressed.Global urbanization contributes to the disease's spread,which is influenced by factors such as population density,cultural beliefs,water storage practices,hygiene,and water supply accessibility.Future prevention strategies must focus on government intervention,community practices,and innovative vector control measures to mitigate the spread of DENV in Nigeria.This study will serve as a valuable reference for policy-makers,researchers,and clinicians in the management and control of DENV in Nigeria and Africa as a whole.展开更多
Objective To clarify the epidemiological characteristics and spatial distribution patterns of human norovirus outbreaks in China, identify high-risk areas, and provide guidance for epidemic prevention and control.Meth...Objective To clarify the epidemiological characteristics and spatial distribution patterns of human norovirus outbreaks in China, identify high-risk areas, and provide guidance for epidemic prevention and control.Methods This study analyzed 964 human norovirus outbreaks involving 50,548 cases in 26 provinces reported from 2012 to 2018. Epidemiological analysis and spatiotemporal scanning analysis were conducted to analyze the distribution of norovirus outbreaks in China.Results The outbreaks showed typical seasonality, with more outbreaks in winter and fewer in summer, and the total number of infected cases increased over time. Schools, especially middle schools and primary schools, are the most common settings of norovirus outbreaks, with the major transmission route being life contact. More outbreaks occurred in southeast coastal areas in China and showed significant spatial aggregation. The highly clustered areas of norovirus outbreaks have expanded northeast over time.Conclusion By identifying the epidemiological characteristics and high-risk areas of norovirus outbreaks, this study provides important scientific support for the development of preventive and control measures for norovirus outbreaks, which is conducive to the administrative management of high-risk settings and reduction of disease burden in susceptible areas.展开更多
Dear Editor,Monkeypox is a zoonosis caused by monkeypox virus (MPXV)infection first reported in Central and West Africa[1]. The first outbreak of monkeypox outside of Africa was reported in2003[2].Afterthat,Israel,the...Dear Editor,Monkeypox is a zoonosis caused by monkeypox virus (MPXV)infection first reported in Central and West Africa[1]. The first outbreak of monkeypox outside of Africa was reported in2003[2].Afterthat,Israel,theUnitedKingdom(UK),Singapore, and other countries have reported monkeypox cases among travelers back from Nigeria since 2018[3].展开更多
Monkeypox(mpox),is a disease from the Poxviridae family that can cause several serious medical issues.This mini-review sought to analyze the existing literature regarding the current mpox outbreak with a focus on the ...Monkeypox(mpox),is a disease from the Poxviridae family that can cause several serious medical issues.This mini-review sought to analyze the existing literature regarding the current mpox outbreak with a focus on the prevalence,diagnostics,and containment measures.Mpox cases have been reported to World Health Organization(WHO)from 85 Member States in all six WHO regions during the period of January 1,2022,through August 3,2022.Standardized or optimized guidelines for the clinical care of patients with mpox are limited,particularly in low-resource settings.In an effort to achieve guidance and meet standards,special attention should be paid to this outbreak in order to eradicate such a rare infectious disease by analyzing prevention and control measures.Patient outcomes may also be poor,and their illnesses may last for a long time.The spectrum of clinical symptoms,including complications and sequelae,as well as aspects of the illness may be indicators of sickness severity and complications;therefore,its clinical presentation must be better understood to improve containment measures.In addition,it is important to create and evaluate a standard of care that takes a variety of parameters into account,including antiviral,immune therapies,and clinical metrics that are particular to mpox.The global emergence of mpox has presented new challenges for public health and has called for further investigation into its epidemiological profile across international contexts.展开更多
In August 2021,three students with diarrhea from the same school visited a local hospital in the S district of Beijing.An epidemic investigation showed that there were more students with diarrhea in the same school an...In August 2021,three students with diarrhea from the same school visited a local hospital in the S district of Beijing.An epidemic investigation showed that there were more students with diarrhea in the same school and they had one meal together.Campylobacter jejuni was isolated from both patients with diarrhea and asymptomatic food handlers;however,the latter also carried Campylobacter coli.Phylogenomic analysis showed that there was a campylobacteriosis outbreak among the students,and the asymptomatic food handler may have been the source of the infection.Routine inspection and surveillance for Campylobacter is needed for the food producing staff,particularly those cooking in the cafeteria in schools or other public food services.展开更多
BACKGROUND Coronavirus disease 2019(COVID-19)is a major and costly public health emergency.AIM To investigate the impact of China’s lockdown policies during the COVID-19 outbreak on the level I trauma center of a ter...BACKGROUND Coronavirus disease 2019(COVID-19)is a major and costly public health emergency.AIM To investigate the impact of China’s lockdown policies during the COVID-19 outbreak on the level I trauma center of a tertiary comprehensive hospital of Traditional Chinese Medicine.METHODS All patients admitted to our trauma center during a lockdown in 2020 and the same period in 2019 were enrolled.We collected data on demographics,daily visits,injury type,injury mechanism,injury severity score,and patient management for comparative analysis.RESULTS The total number of patients in the trauma center of our hospital decreased by 50.38%during the COVID-19 Lockdown in 2020 compared to the same period in 2019.The average number of trauma visits per day in 2019 was 47.94,compared to 23.79 in 2020.Comparing the patients’demographic data,loss of employment was the most predominate characteristic in 2020 compared to 2019,while there was no significant difference in gender,age,and marital status between both periods.During the lockdown period,the proportion of traffic accident-related injuries,injuries due to falls greater than 1.5 m,and mechanical injuries decreased significantly,whereas the proportion of injuries caused by falls less than 1.5 m,cuts,assault,bites,and suicidal tendencies and other injuries increased relatively.In addition,the proportion of patients with minor injuries increased and serious injuries decreased during the lockdown.The hospitalization rate increased significantly,and there was no significant difference in emergency surgery and death rates.CONCLUSION The lockdown policies during the COVID-19 outbreak significantly altered the number and mechanism of traumatic events in our hospital,which can be monitored regularly.Our results suggest that mandatory public health prevention and control measures by the government can reduce the incidence of traumatic events and the severity of traumatic injuries.Emergency surgery and mortality rates remain high,increased because of factors such as family injury and penetrating injury,and hospitalization rates have increased significantly.Therefore,our trauma center still needs to be fully staffed.Finally,from the perspective of the injury mechanism,indoor trauma is a major risk during a lockdown,and it is particularly important to develop prevention strategies for such trauma to reduce the medical burden of the next catastrophic epidemic.展开更多
This study aims to examine the time-varying efficiency of the Turkish stock market’s major stock index and eight sectoral indices,including the industrial,financial,service,information technology,basic metals,tourism...This study aims to examine the time-varying efficiency of the Turkish stock market’s major stock index and eight sectoral indices,including the industrial,financial,service,information technology,basic metals,tourism,real estate investment,and chemical petrol plastic,during the COVID-19 outbreak and the global financial crisis(GFC)within the framework of the adaptive market hypothesis.This study employs multifractal detrended fluctuation analysis to illustrate these sectors’multifractality and short-and long-term dependence.The results show that all sectoral returns have greater persis-tence during the COVID-19 outbreak than during the GFC.Second,the real estate and information technology industries had the lowest levels of efficiency during the GFC and the COVID-19 outbreak.Lastly,the fat-tailed distribution has a greater effect on multifractality in these industries.Our results validate the conclusions of the adaptive market hypothesis,according to which arbitrage opportunities vary over time,and contribute to policy formulation for future outbreak-induced economic crises.展开更多
[Objectives]This study was conducted to clarify the outbreak and disaster characteristics of Sesamia inferens Walker and smut in cane-growing regions in the low-latitude plateau of Yunnan Province,where there is conti...[Objectives]This study was conducted to clarify the outbreak and disaster characteristics of Sesamia inferens Walker and smut in cane-growing regions in the low-latitude plateau of Yunnan Province,where there is continuous high temperature and drought in spring and summer.[Methods]A systematic investigation and analysis was conducted on different varieties in different types of fields in 16 cane-growing regions with outbreak of S.inferens and smut in Yunnan from 2019 to 2021.[Results]The outbreak of S.inferens and smut in cane-growing regions in the low-latitude plateau of Yunnan Province resulted in an average percent of dry hearts in the range of 17.3%-56.3%,and as high as 84.0%in severe cases.70%thiamethoxam seed treatment dispersible powder and clothianidin or thiamethoxam fertilizer granules were ineffective against S.inferens,while 10%monosultap·thiamethoxam or 10%clothianidin·monosultap granules had a significant control efficacy on S.inferens.The average diseased plant rate ranged from 14.8%to 89.7%in susceptible varieties with smut,and was as high as 100%in severe cases.ROC 1,Yuetang 93-159,Yuetang 00-236,and Liucheng 05-136 had strong resistance,with an average diseased plant rate of 0-5.5%and the highest rate of 7.6%.S.inferens and smut both broke out in cane-growing regions with an altitude below 1200 m.It is recommended to pay attention to disease and pest monitoring in cane-growing regions with an altitude below 1200 m,and combine it with the management of new plants and ratoon plants to effectively prevent and control the first and second generation of S.inferens-infested seedlings from March to May.It is also recommended to strengthen the promotion and application of excellent disease-resistant varieties,so as to achieve a reasonable distribution of varieties and fundamentally control the outbreak and epidemic of sugarcane smut.[Conclusions]This study provides a basis for the effective prevention and control of catastrophic S.inferens and smut caused by extreme climate.展开更多
Objectives: This research aims to focus on the differences in mpox outbreaks that occurred in 2003 and 2022 in the United States. Methods: We searched the following databases Medline, Google Scholar, Gayle Power Searc...Objectives: This research aims to focus on the differences in mpox outbreaks that occurred in 2003 and 2022 in the United States. Methods: We searched the following databases Medline, Google Scholar, Gayle Power Search, PubMed, and Springerlink using the following search terms “mpox virus”, “MPX”, “mpox in the US”, “US mpox virus 2003”, “US mpox virus 2022”, “US mpox outbreak 2003” and US mpox outbreak 2022”. The only articles selected were those written between 2003 and 2022. Results: Findings showed more Mpox research was conducted during the first US Mpox outbreak in 2003 compared to the US Mpox outbreak in 2022. Findings also indicated that the mpox outbreak of 2003 consisted of more animal-to-human transmissions acquired from sick prairie dogs compared to more human-to-human from an infected international traveler from Nigeria to the US. Conclusion: Major differences in the mpox outbreaks in the US include the number, location of lesions, and transmission type. We recommend further research to increase awareness of the human-to-human transmission of mpox via sexual contact to assist healthcare professionals and public health leaders in providing prevention and wellness in US communities.展开更多
[Objective] This study aimed to investigate an outbreak of apple valsa canker (Valsa ceratosperma) in Yantai apple producing area in 2011 and analyze the major causes of the disease. [Method] In May 2011, 21 commerc...[Objective] This study aimed to investigate an outbreak of apple valsa canker (Valsa ceratosperma) in Yantai apple producing area in 2011 and analyze the major causes of the disease. [Method] In May 2011, 21 commercial apple or-chards in Qixia, Haiyang and Laiyang were selected to investigate the outbreak of applevalsa canker. [Result]The results showed that apple canker occurred seriously in Yantai apple producing area in 2011. The ratio of diseased plants with new canker scars was 68.20% and the ratio of dead plants infected with Valsa cer-atosperma was 2.76%. The average ratios of diseased branches and one-year-old dead branches were 23.98% and 10.74%, respectively. The percentage of orchards with more than 50% diseased plants accounted for 25%-30% of the total number of orchards investigated, and the overal prevalence situation was more serious than normal years. In the investigation, 967 new canker scars were observed, with an average of 2.32 canker scars per plant. Specifical y, 80.04% canker scars were de-veloped from pruning wounds; 60.29% canker scars were developed from previous scars. [Conclusion] The long-period precipitation in the autumn of 2010, low temper-ature in the winter of 2010 and the severe drought in the spring of 2011 might be the major factors causing the outbreak of apple valsa canker in Yantai apple pro-ducing area in 2011. Pruning wounds were the main infection entrances of V. cer-atosperma, and the recurrence in previous scars was the main reason for the out-break of apple canker in spring.展开更多
Based on the data of 18 cases during the past 30 years from 1978 to 2007,the major meteorological conditions for outbreak of blue-green alga in Hongze Lake were analyzed.The results showed that the main meteorological...Based on the data of 18 cases during the past 30 years from 1978 to 2007,the major meteorological conditions for outbreak of blue-green alga in Hongze Lake were analyzed.The results showed that the main meteorological conditions that affected the production and outbreak of blue-green alga were unusual high monthly average temperature,less precipitation and more sunshine hours in ten days.Through the selection of 1 or 0 factors on the values of above meteorological conditions over the years,if the conditions were accorded with the outbreak of blue-green alga,the factor was signed as 1,or it would be signed as 0;if there was outbreak of blue-green alga within ten days,it was signed as 1,or it would be signed as 0;crossing interrelated and integrated prediction method was adopted to establish the prediction equation for outbreak of blue-green alga,the historical fitting rate was 87.5%,and the predicting accuracy rate in 2008-2009 was 87.5%.In addition to meteorological conditions,outbreak of blue-green alga was also influenced by industrial pollutions,etc.,which should be considered in the forecasting procedures.展开更多
Since the water supply crisis in the Taihu Lake on May 29,2007,the control of the Taihu Lake has achieved remarkable results,and the eutrophication has been greatly reduced.Existing problems are as follows:outbreaks o...Since the water supply crisis in the Taihu Lake on May 29,2007,the control of the Taihu Lake has achieved remarkable results,and the eutrophication has been greatly reduced.Existing problems are as follows:outbreaks of blue-green alga still appear seriously every year,and there is no goal to eliminate outbreaks of blue-green alga;the load into the lake greatly exceeds the environmental capacity;reed wetlands are greatly reduced;there is still the possibility of a water supply crisis;the research of eliminating outbreak of blue-green alga is weak.In this paper,the experience of controlling the Taihu Lake is summarized,and the ultimate goals of eliminating eutrophication and outbreaks of blue-green alga and restoring wetlands and biodiversity are proposed.Control measures are proposed,such as deepening the promotion of the lake chief system,establishing the lake chief system in an all-round way,and increasing applied scientific and technological efforts and capital investment.The necessity and possibility of further controlling the Taihu Lake to eliminate outbreaks of blue-green alga should be recognized.Relying on controlling eutrophication alone cannot eliminate outbreaks of blue-green alga.The point that phosphorus control is the key to eliminate outbreaks of blue-green alga is not suitable for the Taihu Lake.The integration ideas of"three types"of technologies should be innovated.The first one is"double reduction and double increase"measures to eliminate eutrophication,of which"double reduction"is to reduce external point sources and non-point sources and internal blue-green alga in sediment;for external sources,the treatment standard of sewage plants should be paid special attention to.The second one is"double algae removal"measures to salvage blue-green alga,suppresses and kills algae.The blue-green alga on the surface,middle and bottom of water should be thoroughly salvaged and eliminated from various water areas.The third one is"double restoration"measures to restore wetlands and biodiversity.The area of wetlands should be restored to the area from the 1960s to the 1970s before outbreaks of blue-green alga,and vegetation coverage reaches 25%-30%.The Taihu Lake is controlled in different waters to ensure water supply safety in water sources.Five suggestions are proposed,such as revising the"Overall Plan for the Comprehensive Treatment of Water Environment in the Taihu Lake Basin"again,incorporating the goal of eliminating outbreaks of blue-green alga in the plan,setting up this research topic,greatly improving sewage treatment standards in local legislation.展开更多
AIM:To report an acute gastroenteritis outbreak caused by a genogroup 2 genotype 6(GII.6) strain norovirus in Shanghai,China.METHODS:Noroviruses are responsible for approximately half of all reported gastroenteritis o...AIM:To report an acute gastroenteritis outbreak caused by a genogroup 2 genotype 6(GII.6) strain norovirus in Shanghai,China.METHODS:Noroviruses are responsible for approximately half of all reported gastroenteritis outbreaks in many countries.Genogroup 2 genotype 4 strains are the most prevalent.Rare outbreaks caused by GII.6 strains have been reported.An acute gastroenteritis outbreak occurred in an elementary school in Shanghai in December of 2013.Field and molecular epidemiologic investigations were conducted.RESULTS:The outbreak was limited to one class in an elementary school located in southwest Shanghai.The age of the students ranged from 9 to 10 years.The first case emerged on December 10,2013,and the last case emerged on December 14,2013.The cases peaked on December 11,2013,with 21 new cases.Of 45 students in the class,32 were affected.The main symptom was gastroenteritis,and 15.6%(5/32) of the cases exhibited a fever.A field epidemiologic investigation showed the pathogen may have been transmitted to the elementary school from employees in a delicatessen via the first case student,who had eaten food from the delicatessen one day before the gastroenteritis episodes began.A molecular epidemiologic investigation identified the cause of the gastroenteritis as norovirus strain GII.6;the viral sequence of the student cases showed 100% homology with that of the shop employees.Genetic relatedness analyses showed that the new viral strain is closely related to previously reported GII.6 sequences,especially to a strain reported in Japan.CONCLUSION:This is the first report to show that norovirus strain GII.6 can cause a gastroenteritis outbreak.Thus,the prevalence of GII.6 noroviruses requires attention.展开更多
Outbreak of a new emerging disease is usually an important consideration in medicine and public health. In December 2019, a new emerging disease started in China and becomes the global concern in early January 2020[1,...Outbreak of a new emerging disease is usually an important consideration in medicine and public health. In December 2019, a new emerging disease started in China and becomes the global concern in early January 2020[1,2]. The disease, 2019-novel coronavirus(2019-nCoV) infection, already existed outside China and the importation of disease is the cause of emerging 2019-nCoV infections in new settings.展开更多
AIM:To investigate the protective efficacy of H2 strain attenuated live hepatitis A vaccines (H2-strain vaccines) in hepatitis A (HA) outbreaks.METHODS:With the permission of their parents, 5551 pre-school and grade 1...AIM:To investigate the protective efficacy of H2 strain attenuated live hepatitis A vaccines (H2-strain vaccines) in hepatitis A (HA) outbreaks.METHODS:With the permission of their parents, 5551 pre-school and grade 1-3 primary school children were inoculated with 1 dose (10(6.5) TCID(50)) of H2 strain vaccines in a nonrandomized, controlled trial conducted in Fucheng County, Hebei Province in May 1997.Another 6485 children in the same grades and compatible in gender and age were enrolled as controls. Epidemiological and serological survey was conducted to evaluate the protective efficacy of the vaccines. ELISA was used to detect serum IgM anti-HAV.RESULTS:HA outbreak started in early May 1998, peaked in the middle of the same month, and lasted about 80 days. Overall 302 HA cases were found, 192(63.58%) were 5-9 years old. One vaccinee and 25 control cases were found to have hepatitis A, which account for 0.28% (1/356) and 5.92% (25/422) of all vaccinees and controls in the 14 villages, respectively. The protective efficacy of vaccines was 95.27% (95% CI: 85.83%-104.72%). In subjects tested for anti-HAV IgM from 13 villages, 1(0.40%) overt and 11(4.06%) asymptomatic HAV cases were found in 271 vaccinees but 21(6.69%) of overt and asymptomatic ones were found in 314 controls.CONCLUSION:H2 strain vaccines were excellent in preventing overt hepatitis A,but not so effective in preventing asymptomatic hepatitis A virus infection.A booster dose might be needed to get permanent reliable immunity.展开更多
In 1991, in Daxingan Mountain, an outbreak of larch caterpillar (Dendrolim us superans Butler) happened on large areas of more than one million hectares, where stands of larch were seriously damaged because needles on...In 1991, in Daxingan Mountain, an outbreak of larch caterpillar (Dendrolim us superans Butler) happened on large areas of more than one million hectares, where stands of larch were seriously damaged because needles on the trees were almost eaten up by the pest. causing enormous economic losses. Analysis of data collected indicated that the main cause of the outbreak of larch caterpillar on large areas was that, after thirty years of exploitation, mature and overmature forests decreased rapidly. middle-aged and young forests incresed in large amount. significant changes occurred in individual ecological conditions of stands, especially those tended. with decreasing canoPy density and better light condition in the forest, and all these were adventageous to the outbreak of the pest. In addition, in recent years, the climatic condition in Daxingan Mountain changed significantly. The yearly average temperature raised gradually and the soil surface temperature in April and October increased year by year, which were advantageous to the outbreak of larch caterpillars. In short. the significant changes in the ecological conditions in Daxingan Mountain provided suitable conditions for the outbreak of the larch caberpill ar, and after several years of increase in population number, the larch caterpillar outbroke into a serious disaster on vast areas. In the paper, composite control strategy was also discussed.展开更多
文摘Objective:To investigate the importance of immunization in preventing measles infection and to determine the most useful laboratory tests for confirmation of measles.Methods:This study included pediatric cases evaluated with a presumed diagnosis of measles between December 2022 and June 2023,at Marmara University Pendik Training and Research Hospital.The effects of vaccination status and underlying disease on the clinical course,treatments,and complications were evaluated.Results:In total,117 patients were enrolled in the study with a median age of 80 months(IQR:32.5-125.0).Twelve patients with contact history were asymptomatic and had an underlying disorder,and intravenous immunoglobulin was given to them for post-exposure prophylaxis.Fifty-one patients had confirmed measles diagnosis.Ribavirin treatment was given to three patients(a newborn,a girl with rhabdomyosarcoma,and a healthy boy)with respiratory distress.Seventy-eight percent of confirmed measles cases were unvaccinated,and all hospitalized cases were unvaccinated or under-vaccinated.Four full-vaccinated children had confirmed measles infection.Measles PCR from nasopharyngeal swabs was negative in all of them,and their diagnosis was established with anti-measles IgM positivity.Conclusions:The measles vaccine is the most effective way to protect from measles and measles-related complications.Although measles can also occur in fully vaccinated patients,the disease is milder than in unvaccinated patients.Using ELISA and RT-PCR tests together may be beneficial in patients with high clinical suspicion for early diagnosis.
基金Supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(Nos.XDA22050302,XDB42000000)the Taishan Scholar Project Special Fund(to Nansheng CHEN)the Post-doctoral Program of Qingdao 2021(No.E2KY14101N)。
文摘A sudden and unprecedented outbreak of molluscan Philine kinglipini occurred in summer 2022 in Jiaozhou Bay,Shandong,China,causing substantial damage to local mariculture industry of the Manila clam Ruditapes philippinarum.Although P.kinglipini has been found in many coastal regions of China,the molecular research of P.kinglipini has not been extensively studied,making it difficult to accurately identify and track P.kinglipini samples in field using molecular methods.Samples were collected during the outbreak and their morphological features and molecular sequences were analyzed.Results show that the causative species of the outbreak was P.kinglipini.The mitochondrial genome(mt DNA)of P.kinglipini was constructed for the first time,based on which phylogenetic analysis of the mt DNAs of P.kinglipini and related species in the order Cephalaspidea was carried out.As revealed by metabarcoding analysis of 18S rDNA V4,the seasonal change of P.kinglipini and closely related Philine species was striking with peaks between April and August.Therefore,metabarcoding analysis is applicable tool for monitoring the bloom development of P.kinglipini and related species.This study generated for the first time essential molecular marker sequences and mtDNA of P.kinglipini,which provided a reference for future characterization and monitoring of its outbreaks and for phylogenetic analysis of Philine species.
文摘Mpox disease is caused by a double-stranded DNA virus, genus Orthopoxvirus of the family Poxviridae. The incubation period is usually 6 to 13 days but can range from 5 to 21 days while symptoms and signs may persist for 2 to 5 weeks. Although, the clinical features are usually less severe when compared to the deadly smallpox, the disease can be fatal with case fatality rate between 1% and 10%. In Imo State, Nigeria, there has been a changing epidemiology of the disease in the last 6 years and the frequency and geographic distribution of cases have progressively increased. This study aims to conduct a review of the disease epidemiology between 2017 and 2023 and implications for surveillance in Imo State. Surveillance data from the Surveillance Outbreak Response and Management System (SORMAS) was extracted between January 2017 and December 2023 across the 27 Local Government Areas (LGAs) of Imo State. A line list of 231 suspected cases was downloaded into an excel template and analyzed using SPSS<sup>®</sup> version 20 software. Analysis was done using descriptive statistics and associations were tested using Fischer’s exact at 0.05 level of significance. Of the 231 suspected cases, 57.1% (132) were males, 42.9% (99) were females and the modal age group was between the ages of 0 - 4 (32.5%). Eight (8) LGAs (districts) accounted for 71% (n = 164) of all the suspected cases. 21.2% (49) were confirmed positive, 27 males (55.1%) and 22 females (44.9%) (p > 0.05). Modal age group was 20 - 24 (22.4%, n = 11), 18% (9) were children under 14 years, p > 0.05. Case fatality rate was 8% (n = 4). There was no significant association between mortality and age group. Five (5) LGAs accounted for about 60% (29) of all confirmed cases. These LGAs contribute only 20% to the total population in the State. Only 5.6% and 4% of suspected and confirmed cases, respectively, had knowledge of contact with an infectious source. The study described the epidemiology of Mpox outbreaks between 2017 and 2023 and the findings have significant implications on detection and outbreak response activities.
文摘Dengue fever(DF)has become a major public health concern in Nepal,with increasing outbreaks in recent years.Transmitted by Aedes mosquitoes,this climate-sensitive viral disease presents a significant challenge for healthcare providers and policymakers.Since 2004,Nepal has experienced a sharp increase in DF cases,peaking in 2022 with 54784 cases and 88 deaths.The surge,driven mainly by serotypes 1,2,and 3,is exacerbated by climate change,which prolongs mosquito breeding seasons due to warmer temperatures and increased rainfall.This trend has even impacted previously unaffected hilly regions.Effective dengue control strategies must focus on climate change adaptation,strengthening healthcare system reinforcement,raising public awareness,and enhancing vector control measures.Government initiatives,like the national dengue control program,play a critical role,but research and community engagement are also vital for prevention and early detection.Integrating climate resilience into public health efforts is essential to reducing the dengue burden in Nepal.
文摘Dengue fever,caused by the dengue virus(DENV),poses a significant public health challenge globally,with Nigeria experiencing sporadic outbreaks.A clear understanding of the dengue burden has not been achieved in Nigeria,just as in other African countries.Understanding the epidemiology and burden of dengue fever is essential for effective prevention and control strategies.This paper examines the recent dengue outbreaks in northern Nigeria,particularly in Sokoto state,and evaluates the recommended Takeda dengue vaccine(TDV)along with future prevention strategies.Despite limited surveillance and underreporting,dengue fever is endemic in Nigeria(with over 5 million cases and 5000 dengue-related deaths in 2023),with recent outbreaks indicating a growing concern.The TDV,a live attenuated tetravalent vaccine,has shown promise in preventing dengue fever,but challenges such as vaccine acceptance and access-ibility need to be addressed.Global urbanization contributes to the disease's spread,which is influenced by factors such as population density,cultural beliefs,water storage practices,hygiene,and water supply accessibility.Future prevention strategies must focus on government intervention,community practices,and innovative vector control measures to mitigate the spread of DENV in Nigeria.This study will serve as a valuable reference for policy-makers,researchers,and clinicians in the management and control of DENV in Nigeria and Africa as a whole.
基金supported by the National Natural Science Foundation of China[grant number 81903377]Young Scholar Foundation of NIEH[grant number 19qnjj]。
文摘Objective To clarify the epidemiological characteristics and spatial distribution patterns of human norovirus outbreaks in China, identify high-risk areas, and provide guidance for epidemic prevention and control.Methods This study analyzed 964 human norovirus outbreaks involving 50,548 cases in 26 provinces reported from 2012 to 2018. Epidemiological analysis and spatiotemporal scanning analysis were conducted to analyze the distribution of norovirus outbreaks in China.Results The outbreaks showed typical seasonality, with more outbreaks in winter and fewer in summer, and the total number of infected cases increased over time. Schools, especially middle schools and primary schools, are the most common settings of norovirus outbreaks, with the major transmission route being life contact. More outbreaks occurred in southeast coastal areas in China and showed significant spatial aggregation. The highly clustered areas of norovirus outbreaks have expanded northeast over time.Conclusion By identifying the epidemiological characteristics and high-risk areas of norovirus outbreaks, this study provides important scientific support for the development of preventive and control measures for norovirus outbreaks, which is conducive to the administrative management of high-risk settings and reduction of disease burden in susceptible areas.
文摘Dear Editor,Monkeypox is a zoonosis caused by monkeypox virus (MPXV)infection first reported in Central and West Africa[1]. The first outbreak of monkeypox outside of Africa was reported in2003[2].Afterthat,Israel,theUnitedKingdom(UK),Singapore, and other countries have reported monkeypox cases among travelers back from Nigeria since 2018[3].
文摘Monkeypox(mpox),is a disease from the Poxviridae family that can cause several serious medical issues.This mini-review sought to analyze the existing literature regarding the current mpox outbreak with a focus on the prevalence,diagnostics,and containment measures.Mpox cases have been reported to World Health Organization(WHO)from 85 Member States in all six WHO regions during the period of January 1,2022,through August 3,2022.Standardized or optimized guidelines for the clinical care of patients with mpox are limited,particularly in low-resource settings.In an effort to achieve guidance and meet standards,special attention should be paid to this outbreak in order to eradicate such a rare infectious disease by analyzing prevention and control measures.Patient outcomes may also be poor,and their illnesses may last for a long time.The spectrum of clinical symptoms,including complications and sequelae,as well as aspects of the illness may be indicators of sickness severity and complications;therefore,its clinical presentation must be better understood to improve containment measures.In addition,it is important to create and evaluate a standard of care that takes a variety of parameters into account,including antiviral,immune therapies,and clinical metrics that are particular to mpox.The global emergence of mpox has presented new challenges for public health and has called for further investigation into its epidemiological profile across international contexts.
基金supported by the National Key Research and Development Program of China[2021YFC2301000].
文摘In August 2021,three students with diarrhea from the same school visited a local hospital in the S district of Beijing.An epidemic investigation showed that there were more students with diarrhea in the same school and they had one meal together.Campylobacter jejuni was isolated from both patients with diarrhea and asymptomatic food handlers;however,the latter also carried Campylobacter coli.Phylogenomic analysis showed that there was a campylobacteriosis outbreak among the students,and the asymptomatic food handler may have been the source of the infection.Routine inspection and surveillance for Campylobacter is needed for the food producing staff,particularly those cooking in the cafeteria in schools or other public food services.
基金study was reviewed and approved by the Foshan Hospital of TCM Institutional Review Board,No.KY[2023]024.
文摘BACKGROUND Coronavirus disease 2019(COVID-19)is a major and costly public health emergency.AIM To investigate the impact of China’s lockdown policies during the COVID-19 outbreak on the level I trauma center of a tertiary comprehensive hospital of Traditional Chinese Medicine.METHODS All patients admitted to our trauma center during a lockdown in 2020 and the same period in 2019 were enrolled.We collected data on demographics,daily visits,injury type,injury mechanism,injury severity score,and patient management for comparative analysis.RESULTS The total number of patients in the trauma center of our hospital decreased by 50.38%during the COVID-19 Lockdown in 2020 compared to the same period in 2019.The average number of trauma visits per day in 2019 was 47.94,compared to 23.79 in 2020.Comparing the patients’demographic data,loss of employment was the most predominate characteristic in 2020 compared to 2019,while there was no significant difference in gender,age,and marital status between both periods.During the lockdown period,the proportion of traffic accident-related injuries,injuries due to falls greater than 1.5 m,and mechanical injuries decreased significantly,whereas the proportion of injuries caused by falls less than 1.5 m,cuts,assault,bites,and suicidal tendencies and other injuries increased relatively.In addition,the proportion of patients with minor injuries increased and serious injuries decreased during the lockdown.The hospitalization rate increased significantly,and there was no significant difference in emergency surgery and death rates.CONCLUSION The lockdown policies during the COVID-19 outbreak significantly altered the number and mechanism of traumatic events in our hospital,which can be monitored regularly.Our results suggest that mandatory public health prevention and control measures by the government can reduce the incidence of traumatic events and the severity of traumatic injuries.Emergency surgery and mortality rates remain high,increased because of factors such as family injury and penetrating injury,and hospitalization rates have increased significantly.Therefore,our trauma center still needs to be fully staffed.Finally,from the perspective of the injury mechanism,indoor trauma is a major risk during a lockdown,and it is particularly important to develop prevention strategies for such trauma to reduce the medical burden of the next catastrophic epidemic.
文摘This study aims to examine the time-varying efficiency of the Turkish stock market’s major stock index and eight sectoral indices,including the industrial,financial,service,information technology,basic metals,tourism,real estate investment,and chemical petrol plastic,during the COVID-19 outbreak and the global financial crisis(GFC)within the framework of the adaptive market hypothesis.This study employs multifractal detrended fluctuation analysis to illustrate these sectors’multifractality and short-and long-term dependence.The results show that all sectoral returns have greater persis-tence during the COVID-19 outbreak than during the GFC.Second,the real estate and information technology industries had the lowest levels of efficiency during the GFC and the COVID-19 outbreak.Lastly,the fat-tailed distribution has a greater effect on multifractality in these industries.Our results validate the conclusions of the adaptive market hypothesis,according to which arbitrage opportunities vary over time,and contribute to policy formulation for future outbreak-induced economic crises.
基金Supported by China Agriculture Research System of MOF and MARA(CARS-170303)Yunling Industrial Technology Leading Talent Training Project(2018LJRC56)Special Fund for the Construction of Modern Agricultural Industry Technology System in Yunnan Province。
文摘[Objectives]This study was conducted to clarify the outbreak and disaster characteristics of Sesamia inferens Walker and smut in cane-growing regions in the low-latitude plateau of Yunnan Province,where there is continuous high temperature and drought in spring and summer.[Methods]A systematic investigation and analysis was conducted on different varieties in different types of fields in 16 cane-growing regions with outbreak of S.inferens and smut in Yunnan from 2019 to 2021.[Results]The outbreak of S.inferens and smut in cane-growing regions in the low-latitude plateau of Yunnan Province resulted in an average percent of dry hearts in the range of 17.3%-56.3%,and as high as 84.0%in severe cases.70%thiamethoxam seed treatment dispersible powder and clothianidin or thiamethoxam fertilizer granules were ineffective against S.inferens,while 10%monosultap·thiamethoxam or 10%clothianidin·monosultap granules had a significant control efficacy on S.inferens.The average diseased plant rate ranged from 14.8%to 89.7%in susceptible varieties with smut,and was as high as 100%in severe cases.ROC 1,Yuetang 93-159,Yuetang 00-236,and Liucheng 05-136 had strong resistance,with an average diseased plant rate of 0-5.5%and the highest rate of 7.6%.S.inferens and smut both broke out in cane-growing regions with an altitude below 1200 m.It is recommended to pay attention to disease and pest monitoring in cane-growing regions with an altitude below 1200 m,and combine it with the management of new plants and ratoon plants to effectively prevent and control the first and second generation of S.inferens-infested seedlings from March to May.It is also recommended to strengthen the promotion and application of excellent disease-resistant varieties,so as to achieve a reasonable distribution of varieties and fundamentally control the outbreak and epidemic of sugarcane smut.[Conclusions]This study provides a basis for the effective prevention and control of catastrophic S.inferens and smut caused by extreme climate.
文摘Objectives: This research aims to focus on the differences in mpox outbreaks that occurred in 2003 and 2022 in the United States. Methods: We searched the following databases Medline, Google Scholar, Gayle Power Search, PubMed, and Springerlink using the following search terms “mpox virus”, “MPX”, “mpox in the US”, “US mpox virus 2003”, “US mpox virus 2022”, “US mpox outbreak 2003” and US mpox outbreak 2022”. The only articles selected were those written between 2003 and 2022. Results: Findings showed more Mpox research was conducted during the first US Mpox outbreak in 2003 compared to the US Mpox outbreak in 2022. Findings also indicated that the mpox outbreak of 2003 consisted of more animal-to-human transmissions acquired from sick prairie dogs compared to more human-to-human from an infected international traveler from Nigeria to the US. Conclusion: Major differences in the mpox outbreaks in the US include the number, location of lesions, and transmission type. We recommend further research to increase awareness of the human-to-human transmission of mpox via sexual contact to assist healthcare professionals and public health leaders in providing prevention and wellness in US communities.
基金Supported by National Modern Industrial Technology System of Apple(CARS-28)National Natural Science Foundation of China(31000891)~~
文摘[Objective] This study aimed to investigate an outbreak of apple valsa canker (Valsa ceratosperma) in Yantai apple producing area in 2011 and analyze the major causes of the disease. [Method] In May 2011, 21 commercial apple or-chards in Qixia, Haiyang and Laiyang were selected to investigate the outbreak of applevalsa canker. [Result]The results showed that apple canker occurred seriously in Yantai apple producing area in 2011. The ratio of diseased plants with new canker scars was 68.20% and the ratio of dead plants infected with Valsa cer-atosperma was 2.76%. The average ratios of diseased branches and one-year-old dead branches were 23.98% and 10.74%, respectively. The percentage of orchards with more than 50% diseased plants accounted for 25%-30% of the total number of orchards investigated, and the overal prevalence situation was more serious than normal years. In the investigation, 967 new canker scars were observed, with an average of 2.32 canker scars per plant. Specifical y, 80.04% canker scars were de-veloped from pruning wounds; 60.29% canker scars were developed from previous scars. [Conclusion] The long-period precipitation in the autumn of 2010, low temper-ature in the winter of 2010 and the severe drought in the spring of 2011 might be the major factors causing the outbreak of apple valsa canker in Yantai apple pro-ducing area in 2011. Pruning wounds were the main infection entrances of V. cer-atosperma, and the recurrence in previous scars was the main reason for the out-break of apple canker in spring.
文摘Based on the data of 18 cases during the past 30 years from 1978 to 2007,the major meteorological conditions for outbreak of blue-green alga in Hongze Lake were analyzed.The results showed that the main meteorological conditions that affected the production and outbreak of blue-green alga were unusual high monthly average temperature,less precipitation and more sunshine hours in ten days.Through the selection of 1 or 0 factors on the values of above meteorological conditions over the years,if the conditions were accorded with the outbreak of blue-green alga,the factor was signed as 1,or it would be signed as 0;if there was outbreak of blue-green alga within ten days,it was signed as 1,or it would be signed as 0;crossing interrelated and integrated prediction method was adopted to establish the prediction equation for outbreak of blue-green alga,the historical fitting rate was 87.5%,and the predicting accuracy rate in 2008-2009 was 87.5%.In addition to meteorological conditions,outbreak of blue-green alga was also influenced by industrial pollutions,etc.,which should be considered in the forecasting procedures.
文摘Since the water supply crisis in the Taihu Lake on May 29,2007,the control of the Taihu Lake has achieved remarkable results,and the eutrophication has been greatly reduced.Existing problems are as follows:outbreaks of blue-green alga still appear seriously every year,and there is no goal to eliminate outbreaks of blue-green alga;the load into the lake greatly exceeds the environmental capacity;reed wetlands are greatly reduced;there is still the possibility of a water supply crisis;the research of eliminating outbreak of blue-green alga is weak.In this paper,the experience of controlling the Taihu Lake is summarized,and the ultimate goals of eliminating eutrophication and outbreaks of blue-green alga and restoring wetlands and biodiversity are proposed.Control measures are proposed,such as deepening the promotion of the lake chief system,establishing the lake chief system in an all-round way,and increasing applied scientific and technological efforts and capital investment.The necessity and possibility of further controlling the Taihu Lake to eliminate outbreaks of blue-green alga should be recognized.Relying on controlling eutrophication alone cannot eliminate outbreaks of blue-green alga.The point that phosphorus control is the key to eliminate outbreaks of blue-green alga is not suitable for the Taihu Lake.The integration ideas of"three types"of technologies should be innovated.The first one is"double reduction and double increase"measures to eliminate eutrophication,of which"double reduction"is to reduce external point sources and non-point sources and internal blue-green alga in sediment;for external sources,the treatment standard of sewage plants should be paid special attention to.The second one is"double algae removal"measures to salvage blue-green alga,suppresses and kills algae.The blue-green alga on the surface,middle and bottom of water should be thoroughly salvaged and eliminated from various water areas.The third one is"double restoration"measures to restore wetlands and biodiversity.The area of wetlands should be restored to the area from the 1960s to the 1970s before outbreaks of blue-green alga,and vegetation coverage reaches 25%-30%.The Taihu Lake is controlled in different waters to ensure water supply safety in water sources.Five suggestions are proposed,such as revising the"Overall Plan for the Comprehensive Treatment of Water Environment in the Taihu Lake Basin"again,incorporating the goal of eliminating outbreaks of blue-green alga in the plan,setting up this research topic,greatly improving sewage treatment standards in local legislation.
文摘AIM:To report an acute gastroenteritis outbreak caused by a genogroup 2 genotype 6(GII.6) strain norovirus in Shanghai,China.METHODS:Noroviruses are responsible for approximately half of all reported gastroenteritis outbreaks in many countries.Genogroup 2 genotype 4 strains are the most prevalent.Rare outbreaks caused by GII.6 strains have been reported.An acute gastroenteritis outbreak occurred in an elementary school in Shanghai in December of 2013.Field and molecular epidemiologic investigations were conducted.RESULTS:The outbreak was limited to one class in an elementary school located in southwest Shanghai.The age of the students ranged from 9 to 10 years.The first case emerged on December 10,2013,and the last case emerged on December 14,2013.The cases peaked on December 11,2013,with 21 new cases.Of 45 students in the class,32 were affected.The main symptom was gastroenteritis,and 15.6%(5/32) of the cases exhibited a fever.A field epidemiologic investigation showed the pathogen may have been transmitted to the elementary school from employees in a delicatessen via the first case student,who had eaten food from the delicatessen one day before the gastroenteritis episodes began.A molecular epidemiologic investigation identified the cause of the gastroenteritis as norovirus strain GII.6;the viral sequence of the student cases showed 100% homology with that of the shop employees.Genetic relatedness analyses showed that the new viral strain is closely related to previously reported GII.6 sequences,especially to a strain reported in Japan.CONCLUSION:This is the first report to show that norovirus strain GII.6 can cause a gastroenteritis outbreak.Thus,the prevalence of GII.6 noroviruses requires attention.
文摘Outbreak of a new emerging disease is usually an important consideration in medicine and public health. In December 2019, a new emerging disease started in China and becomes the global concern in early January 2020[1,2]. The disease, 2019-novel coronavirus(2019-nCoV) infection, already existed outside China and the importation of disease is the cause of emerging 2019-nCoV infections in new settings.
基金national ninth five-year study program for tackling key scientific problems,No.03-01-01
文摘AIM:To investigate the protective efficacy of H2 strain attenuated live hepatitis A vaccines (H2-strain vaccines) in hepatitis A (HA) outbreaks.METHODS:With the permission of their parents, 5551 pre-school and grade 1-3 primary school children were inoculated with 1 dose (10(6.5) TCID(50)) of H2 strain vaccines in a nonrandomized, controlled trial conducted in Fucheng County, Hebei Province in May 1997.Another 6485 children in the same grades and compatible in gender and age were enrolled as controls. Epidemiological and serological survey was conducted to evaluate the protective efficacy of the vaccines. ELISA was used to detect serum IgM anti-HAV.RESULTS:HA outbreak started in early May 1998, peaked in the middle of the same month, and lasted about 80 days. Overall 302 HA cases were found, 192(63.58%) were 5-9 years old. One vaccinee and 25 control cases were found to have hepatitis A, which account for 0.28% (1/356) and 5.92% (25/422) of all vaccinees and controls in the 14 villages, respectively. The protective efficacy of vaccines was 95.27% (95% CI: 85.83%-104.72%). In subjects tested for anti-HAV IgM from 13 villages, 1(0.40%) overt and 11(4.06%) asymptomatic HAV cases were found in 271 vaccinees but 21(6.69%) of overt and asymptomatic ones were found in 314 controls.CONCLUSION:H2 strain vaccines were excellent in preventing overt hepatitis A,but not so effective in preventing asymptomatic hepatitis A virus infection.A booster dose might be needed to get permanent reliable immunity.
文摘In 1991, in Daxingan Mountain, an outbreak of larch caterpillar (Dendrolim us superans Butler) happened on large areas of more than one million hectares, where stands of larch were seriously damaged because needles on the trees were almost eaten up by the pest. causing enormous economic losses. Analysis of data collected indicated that the main cause of the outbreak of larch caterpillar on large areas was that, after thirty years of exploitation, mature and overmature forests decreased rapidly. middle-aged and young forests incresed in large amount. significant changes occurred in individual ecological conditions of stands, especially those tended. with decreasing canoPy density and better light condition in the forest, and all these were adventageous to the outbreak of the pest. In addition, in recent years, the climatic condition in Daxingan Mountain changed significantly. The yearly average temperature raised gradually and the soil surface temperature in April and October increased year by year, which were advantageous to the outbreak of larch caterpillars. In short. the significant changes in the ecological conditions in Daxingan Mountain provided suitable conditions for the outbreak of the larch caberpill ar, and after several years of increase in population number, the larch caterpillar outbroke into a serious disaster on vast areas. In the paper, composite control strategy was also discussed.