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1.
China CDC Wkly ; 6(26): 642-648, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38966313

RESUMO

In 2021, China's domestically produced coronavirus disease 2019 (COVID-19) vaccines received approval from regulatory bodies and were administered worldwide. Due to a low number of infections within China during that period, it became imperative to evaluate the vaccines' real-world effectiveness through international studies. To facilitate this, China CDC launched the COVID-19 Vaccines Evaluation Program (COVEP). This program formed research collaboration agreements with health institutes across five World Health Organization regions, addressing key questions about vaccine performance through ten cooperative agreements. The findings from COVEP projects reinforced confidence, both domestically and globally, in the effectiveness of the vaccines produced in China. Moreover, the outcomes observed internationally were frequently mirrored by later studies conducted within China. COVEP thus pioneered a novel approach for fostering cross-national research collaborations, addressing significant public health issues and exemplifying a framework for international cooperation. This approach is in line with the strategic objectives and other development efforts of China CDC's national disease control and prevention initiatives.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38083682

RESUMO

Many small bionic crawling robots have been invented for search and rescue missions in narrow spaces. However, their locomotion capability is far from that of insects of the same size. Transforming a cockroach into a bio-bot has been a hot topic in the past decade. Herein, we modified this insect to perform surveillance work in dark confined environments. The synergistic electrical stimulation for turning control was proposed by alternating electrical stimulation of the cerci and antennae every 5 trials. The result showed that this method was able to control cockroaches turning steadily 117 times. An electronic backpack was designed, which was capable of transmitting images in real time, and a light emitting diode (LED) was installed on the backpack providing a light source for the camera. Thus, a vision-aided navigation system was formed for dark confined environments, e.g. pipelines. With a host computer software, the operator controlled the bio-bot to pass through a completely dark and closed pipeline. The electronic backpack and the host computer were connected via transmission control protocol (TCP), which allows the operator to manipulate the bio-robot remotely. This technology can be applied in pipeline surveillance in the future.


Assuntos
Baratas , Robótica , Caminhada , Animais , Baratas/fisiologia , Estimulação Elétrica/métodos , Locomoção/fisiologia , Robótica/métodos
3.
Cyborg Bionic Syst ; 4: 0067, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38026542

RESUMO

Tens of crawling bio-robots with cockroaches as the mobile platform have been developed with various functions. Compared with artificial crawling robots of the same size, they revealed better flexibility, larger payload, and stronger endurance. These features made bio-robots ideal for pipeline inspection scenarios because the advancements in locomotion mechanisms and efficient power systems are still hurdles for current artificial systems. In this study, we controlled the bio-robot to crawl in the confined dark pipeline and achieved autonomous motion control with the help of an onboard sensing system. Specifically, a micro-camera was mounted on the electronic backpack of the cockroach for image collection, and an IMU sensor was used to compute its body orientation. The electronic backpack transmitted images to the host computer for junction recognition and distance estimation. Meanwhile, the insect's habituation to electrical stimulation has long been an uncertain factor in the control of bio-robots. Here, a synergistic stimulation strategy was proposed to markedly reduce the habituation and increase the number of effective turning controls to over 100 times. It is also found that both the increase of payload and the application of stimulations could promote the metabolic rate by monitoring carbon dioxide release. With the integration of synergistic stimulation and autonomous control, we demonstrated the fully autonomous pipeline navigation with our cockroach bio-robot, which realized the cycle number of approximately 10 in a roll. This research provides a novel technology that has the potential for practical applications in the future.

4.
Membranes (Basel) ; 12(4)2022 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-35448359

RESUMO

The single-channel Al2O3-based porous ceramic membrane tubes (PCMT) were prepared with different grain size of Al2O3 powders by extrusion molding process, combing the traditional solid-phase sintering method. The effects of raw grain size and sintering temperature on the microstructure, phase structure, density, and porosity were investigated. The results revealed that with further increase in sintering temperature, the density of porous ceramics increases, while the porosity decreases, and the pore size decreases slightly. The pore size and porosity of porous ceramics increase with the increase in raw grain size, while the density decreases. Future, in order to study the water filtration of PCMT, the effect of porosity on the pressure distribution and flow velocity different cross-sectional areas with constant feed mass flow was analyzed using Fluent 19.0. It was found that an increase in the porosity from 30% to 45% with constant feed mass flow influenced transmembrane pressure, that varied from 216.06 kPa to 42.28 kPa, while the velocity change at the outlet was not obvious. Besides, it was observed that the surface pressure is almost constant along the radial direction of the pipe, and the velocity of water in the PCMT is increasing with the decreasing of distance to the outlet. It was also verified that the porosity being 39.64%, caused transmembrane pressure reaching to 77.83 kPa and maximum velocity of 2.301 m/s. These simulation and experimental results showed that the PCMT have good potential for water filtration.

5.
Membranes (Basel) ; 11(11)2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34832101

RESUMO

Air bearing has been widely applied in ultra-precision machine tools, aerospace and other fields. The restrictor of the porous material is the key component in air bearings, but its performance is limited by the machining accuracy. A combination of optimization design and material modification of the porous alumina ceramic membrane is proposed to improve performance within an air bearing. Porous alumina ceramics were prepared by adding a pore-forming agent and performing solid-phase sintering at 1600 °C for 3 h, using 95-Al2O3 as raw material and polystyrene microspheres with different particle sizes as the pore-forming agent. With 20 wt.% of PS50, the optimum porous alumina ceramic membranes achieved a density of 3.2 g/cm3, a porosity of 11.8% and a bending strength of 150.4 MPa. Then, the sintered samples were processed into restrictors with a diameter of 40 mm and a thickness of 5 mm. After the restrictors were bonded to aluminum shells for the air bearing, both experimental and simulation work was carried out to verify the designed air bearing. Simulation results showed that the load capacity increased from 94 N to 523 N when the porosity increased from 5% to 25% at a fixed gas supply pressure of 0.5 MPa and a fixed gas film thickness of 25 µm. When the gas film thickness and porosity were fixed at 100 µm and 11.8%, respectively, the load capacity increased from 8.6 N to 40.8 N with the gas supply pressure having been increased from 0.1 MPa to 0.5 MPa. Both experimental and simulation results successfully demonstrated the stability and effectiveness of the proposed method. The porosity is an important factor for improving the performance of an air bearing, and it can be optimized to enhance the bearing's stability and load capacity.

6.
J Econ Entomol ; 114(4): 1549-1556, 2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-34170292

RESUMO

The ectoparasitoid beetle, Dastarcus helophoroides (Fairmaire) (Coleoptera: Bothrideridae), has been widely used as a biological control agent for many cerambycid beetles in China, Korea, and Japan. However, much less is known about its phototactic behavior to visual stimuli. In this paper, the phototactic behavioral response of D. helophoroides to 27 monochromatic lights and to nine illumination intensities of the most attractive light was evaluated using light-emitting diodes (LEDs) as light sources. The results showed that in dual choice between darkness and individual LED light, D. helophoroides adults exhibited a positively phototactic response to all wavelengths ranging from 300 to 860 nm. The near-infrared light (NIR, ranging from 700 to 760 nm) elicited stronger phototactic behavioral response, showing a preference for NIR wavelengths light. In paired choice among four preferred NIR lights, D. helophoroides adults displayed a significantly more favorable response to NIR light at 700 nm. Furthermore, the beetles expressed varying levels of sensitivity to illumination intensities from 1 to 600 lux under NIR light at 700 nm. The phototactic response was strongest at 7 lux and a statistically significant downward trend was found with increasing or decreasing the illumination intensities. These findings clearly demonstrate that D. helophoroides is a positively phototactic insect and its phototactic behavior is significantly influenced by light wavelength and illumination intensity, among which NIR light with peak wavelength at 700 nm and an intensity at 7 lux are most suitable in attracting D. helophoroides adults.


Assuntos
Besouros , Animais , Agentes de Controle Biológico , China , Japão , Luz
7.
J Econ Entomol ; 113(6): 2634-2640, 2020 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-32964236

RESUMO

The coleopteran parasitoid Dastarcus helophoroides (Fairmaire) (Coleoptera: Bothrideridae) is considered an efficient preventative method against the damage caused by a large number of cerambycid pests in China and other East Asian countries. Mass rearing of this parasitoid depends on screening appropriate factitious hosts. In this paper, the fitness-related traits of this parasitic beetle were explored using pupae of the two tenebrionid beetles, Tenebrio molitor Linnaeus and Zophobas morio Fabricius (Coleoptera: Tenebrionidae) as factitious hosts. The results showed that in dual-choice trials, D. helophoroides larvae preferred to attack Z. morio pupae. In no-choice trials, D. helophoroides reared on Z. morio pupae displayed significantly higher pupation and emergence rate, longer developmental duration of larval and larval-pupal stages, larger adult body size, shorter preoviposition period, more egg masses and egg production, and higher relative expected reproduction than those reared on T. molitor pupae. These results demonstrate that Z. morio is a more suitable factitious host for mass rearing of D. helophoroides.


Assuntos
Besouros , Animais , China , Larva , Fenótipo , Reprodução
8.
Zhongguo Gu Shang ; 32(9): 810-814, 2019 Sep 25.
Artigo em Chinês | MEDLINE | ID: mdl-31615176

RESUMO

OBJECTIVE: To observe and compare the shoulder joint function, complications and clinical effects of hemiarthroplasty and open reduction and locking plate in the treatment of comminuted proximal humeral fracture (Neer IV) with 3D printing technique. METHODS: From March 2012 to April 2018, 31 middle age and elderly patients with comminuted proximal humeral fractures (Neer IV) were treated, including 4 males and 27 females, aged from 55 to 94 years old with an average age of 71 years, with a course of 1 to 3 years. Among them, 20 cases were treated with open reduction and locking plate internal fixation (ORIF group) and 11 cases were treated with lower half shoulder replacement (HA group) assisted by 3D printing technology. Using CT data and Mimics software of Materialise Company in Belgium, the reconstruction of fracture was simulated on computer. The height of fracture end to humeral head, the height of tubercle to humeral head, the angle of humeral head backward obliquity were measured to assist the hemiarthroplasty. Follow-up and X-ray examination were performed, the incidence of complications were observed, and Neer score was used for the shoulder joint function. RESULTS: Thirty-one patients were followed up for 1 to 3 years with an average of 2 years. In HA group, there was no prosthesis loosening, fracture and subsidence, the head of artificial humerus was intact, the fracture of nodules and nodules did not heal in 1 case, Neer score was 84.18±3.55; in ORIF group, there were 8 cases of proximal humerus bone resorption, 1 case of fracture nonunion, 1 case of internal fixation loosening, Neer score was 55.91±10.78; there was significant difference in Neer score of shoulder joint function between the two groups(P<0.05). CONCLUSIONS: Ultrasound-guided minimal traverse-cross technique repair for acute closed Achilles tendon ruptures, which promise minimal incision, protect sural nerve, ensure quality of tendon anastomosis and fixation, and is a ideal method for repairing acute closed Achilles tendon ruptures.


Assuntos
Fraturas Cominutivas , Fraturas do Ombro , Idoso , Idoso de 80 Anos ou mais , Placas Ósseas , Feminino , Fixação Interna de Fraturas , Humanos , Masculino , Pessoa de Meia-Idade , Ombro , Fraturas do Ombro/cirurgia , Resultado do Tratamento
9.
J Food Sci ; 84(6): 1411-1419, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31132162

RESUMO

To improve the mechanical and antibacterial properties of chitosan (CS) films, a ternary blend edible film was prepared by incorporating CS, gelatin (GE), and natural cinnamon essential oil (CEo). Scanning electron microscopy (SEM), Atomic force microscopy (AFM), Fourier transform infrared spectroscopy, and X-ray diffraction were performed to evaluate the films. The mechanical properties, light transmission, thermal stability, hydrophilicity, and antibacterial activity of the films were also determined. The results confirmed all of the films exhibited excellent UV protection with low transparency at 600 nm. Compared with the CS films, the ternary composite film (CSGEo film, containing CS, GE, and CEo) had a higher elongation at break but a lower tensile strength. SEM images revealed that all films had smooth surfaces, although some obvious differences between CS and CSGEo films were observed by AFM. Additionally, the incorporation of GE and CEo to the films enhanced their thermal stability and contact angle, but decreased their crystallinity and wettability. The antimicrobial activity results showed that CSGEo films had excellent antimicrobial activity against Escherichia coli and Staphylococcus aureus, for which the antibacterial rate exceeded 98%. The minimum inhibitory concentrations of the CSGEo solution against E. coli and S. aureus were both 52.06 µg/mL, and the minimal bactericidal concentrations were 104.12 and 52.06 µg/mL, respectively. These results suggest that CSGEo films possess good mechanical and antibacterial properties, and therefore, their application in the food packaging industry is promising. PRACTICAL APPLICATION: The main raw materials of the edible films developed in this study are aquatic by-products, so the films are edible and biodegradable. The addition of gelatin and CEo improved the UV barrier and thermal properties but decreased the crystallinity and hydrophilicity of the films, making them suitable for use as packaging materials. CEo-incorporated films exhibited excellent mechanical properties and antibacterial activity and can, therefore, be used in the food packaging industry.


Assuntos
Anti-Infecciosos , Quitosana , Embalagem de Alimentos/instrumentação , Antibacterianos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Quitosana/química , Cinnamomum zeylanicum/química , Escherichia coli/efeitos dos fármacos , Embalagem de Alimentos/métodos , Gelatina/química , Testes de Sensibilidade Microbiana , Microscopia de Força Atômica , Óleos Voláteis , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus/efeitos dos fármacos , Resistência à Tração , Difração de Raios X
10.
Zhongguo Gu Shang ; 31(2): 120-123, 2018 Feb 25.
Artigo em Chinês | MEDLINE | ID: mdl-29536680

RESUMO

OBJECTIVE: To investigate the preliminary effects of modified percutaneous compression plate in treating femoral neck fractures of Pauwels type III. METHODS: From March 2012 to March 2016, 35 patients with femoral neck fracture were treated by closed reduction and internal fixation with a modified percutaneous compression plate, including 21 males and 14 females with an average age of 45 years old ranging from 23 to 62 years old. The anatomical position of fracture was divided into 8 cases of lower head type, 27 cases of head and neck. According to the Garden classification, there were 8 cases of type II, 18 of type III, and 9 of type IV fractures. All patients were closed injury. The general information, reduction quality, fracture healing time, postoperative complications were recorded and evaluated. Harris scoring was used to evaluate the hip joint function. RESULTS: All patients were followed up for 15 to 24 months with an average of 20 months. All the incisions were primary healing. The reduction quality of the femoral neck fracture was evaluated according to the Garden's alignment Index, and the quality of reduction was grade I reduction in 29 cases and grade II reduction in 6 cases. No nonunion, femoral avascular necrosis, implant failure and hip varus was observed during follow-up. Harris score was(92.70±4.60) points at final follow-up, the results of the treatment was evaluated as excellent in 26 cases, good in 8 cases, fair in 1 case. No complications such as internal fixation loosening, nail breaking, and heterotopic ossification occurred. CONCLUSIONS: Internal fixation with modified percutaneous compression plate has an advantages of decreased trauma, simple operation, rigid fixation, good function outcome, and low risk of complications.


Assuntos
Placas Ósseas , Fraturas do Colo Femoral/cirurgia , Fixação Interna de Fraturas , Consolidação da Fratura , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
11.
Math Biosci ; 298: 91-104, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29477670

RESUMO

Colorado River is a unique ecosystem and provides important ecological services such as habitat for fish species as well as water power energy supplies. River management for this ecosystem requires assessment and decision support tools for fish which involves protecting, restoring as well as forecasting of future conditions. In this paper, a habitat and population model was developed and used to determine the levels of fish habitat suitability and population density in Colorado River between Lees Ferry and Lake Mead. The short term target fish populations are also predicted based on native fish recovery strategy. This model has been developed by combining hydrodynamics, heat transfer and sediment transport models with a habitat suitability index model and then coupling with habitat model into life stage population model. The fish were divided into four life stages according to the fish length. Three most abundant and typical native and non-native fish were selected as target species, which are rainbow trout (Oncorhynchus mykiss), brown trout (Salmo trutta) and flannelmouth sucker (Catostomus latipinnis). Flow velocity, water depth, water temperature and substrates were used as the suitability indicators in habitat model and overall suitability index (OSI) as well as weight usable area (WUA) was used as an indicator in population model. A comparison was made between simulated fish population alteration and surveyed fish number fluctuation during 2000 to 2009. The application of this habitat and population model indicates that this model can be accurate present habitat situation and targets fish population dynamics of in the study areas. The analysis also indicates the flannelmouth sucker population will steadily increase while the rainbow trout will decrease based on the native fish recovery scheme.


Assuntos
Cipriniformes , Ecossistema , Modelos Teóricos , Rios , Truta , Animais , Sudoeste dos Estados Unidos
13.
Zhongguo Gu Shang ; 28(8): 726-9, 2015 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-26502524

RESUMO

OBJECTIVE: To discuss the clinical significance of the reduction and fixation for femoral lesser trochanteric fragment in treating the femoral comminuted intertrochanteric fractures. METHODS: From January 2012 to December 2013,32 patients with intertrochanteric fractures were treated by surgery, and self-designed reduction fixators were used in the patients for the fixation of lesser trochanter of femur. There were 11 males and 21 females, ranging in age from 45 to 81 years old with an average of 64 years old. According to the Evans typing, 12 cases were type II, 13 cases were type III and 7 cases were type IV. Simple lag screw fixed in 19 cases and steel wire fixed in 13 cases. Hip joint function was evaluated according Harris score and the complications such as coxa adducta,cutting of femoral head and neck,implants breakage were observed. RESULTS: Thirty-two patients were followed up from 9 to 24 months with an average of 13 months. Coxa adducta occurred in 1 case,no cutting of femoral head and neck occurred and implants breakage were found. The mean Harris score was 91.80 ± 3.05 in 32 patients. CONCLUSION: The reconstruction and fixation for the posterior medial bone cortex continuity is a key factor on affect the stability of femoral intertrochanteric fracture. Self-designed reduction fixators can effective reduce and fix the lesser trochanter of femur, it has advantage of fast reduction and fixation, and simple operation.


Assuntos
Fixação Interna de Fraturas/instrumentação , Fraturas do Quadril/cirurgia , Idoso , Idoso de 80 Anos ou mais , Desenho de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
14.
Hum Vaccin Immunother ; 11(8): 2061-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26090956

RESUMO

Vaccination in prevention mother-to-child transmission (PMTCT) of hepatitis B has been recommended since plasma-derived hepatitis B vaccines became available in China in 1986; however, less study evaluated practice effectiveness of PMTCT systematically. We conducted a prospective survey to evaluate the effectiveness of PMTCT practices in 3 provinces of southern China. We selected prefectures with low timely birth dose coverage in Yunnan, Guangxi, and Hunan provinces. Infants born to HBsAg positive mothers were evaluated at 7-12 months of age. We tested hepatitis B virus (HBV) surface antigen (HBsAg) and HBV e antigen (HBeAg) of mothers and tested HBsAg of infants born to HBsAg positive mothers using Enzyme-linked Immunosorbent Assay (ELISA) at provincial CDC laboratories. We used logistic regression analysis to analyze the risk factors for HBV infection. Among 3,094 infants born to HBsAg positive mothers, 172 were positive for HBsAg (5.6%). HBeAg status of pregnant women, timely birth dose (TBD) of hepatitis B vaccine were major predictors for HBV infection of infants. PMTCT practices greatly reduced the prevalence of HBsAg among infants born to HBsAg positive mothers China. However, the effectiveness of strategies used in PMTCT varied. HBsAg screening for pregnant women, monitoring of infants born to HBsAg positive mother should be enhanced to evaluate the effectiveness of program.


Assuntos
Antígenos de Superfície da Hepatite B/sangue , Antígenos E da Hepatite B/sangue , Hepatite B/prevenção & controle , Hepatite B/transmissão , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Adulto , China/epidemiologia , Ensaio de Imunoadsorção Enzimática , Feminino , Hepatite B/epidemiologia , Humanos , Lactente , Recém-Nascido , Masculino , Prevalência , Estudos Prospectivos , Fatores de Risco
15.
J Water Health ; 13(2): 510-21, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26042982

RESUMO

Two typical rural water utilities in Beijing, China were chosen to describe the principles and applications of water safety plans (WSP), to provide a methodological guide for the actual application and improve the quality of rural drinking water quality, and to establish an appropriate method for WSP applied in rural water supply. Hazards and hazardous events were identified and risk assessment was conducted for rural water supply systems. A total of 13 and 12 operational limits were defined for two utilities, respectively. The main risk factors that affect the water safety were identified in water sources, water processes, water disinfection systems and water utility management. The main control measures were strengthening the water source protection, monitoring the water treatment processes, establishing emergency mechanisms, improving chemical input and operating system management. WSP can be feasibly applied to the management of a rural water supply.


Assuntos
Qualidade da Água/normas , Abastecimento de Água/normas , China , Monitoramento Ambiental/métodos , Humanos , Medição de Risco , Poluição da Água/prevenção & controle
16.
Zhongguo Gu Shang ; 28(12): 1111-3, 2015 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-26911118

RESUMO

OBJECTIVE: To explore operative clinical outcomes of proximal humeral fracture with rotator cuff tear in elderly patients. METHODS: From March 2010 to August 2014,54 elderly patients with proximal humeral fractures with rotator cuff tear were performed operation, including 30 males and 24 females aged from 68 to 83 years old with an average of 71.5 years old. Thirty patients were caused by falling down, 24 cases were caused by traffic accident. According to Neer classification, 3 cases were part I, 11 cases were part II, 21 cases were part III and 19 cases were part IV. All patients were operated with open reduction and plate internal fixation, 46 cases suffered from rotator cuff tear and carried out repair of rotator cuff; 8 cases were not suffered from rotator cuff tear. Postoperative Neer evaluation of shoulder's function were used to assess clinical results. RESULTS: Forty-six patients with rotator cuff tear were followed up from 8 to 21 months with an average of 11 months. All fractures were obtained bone union. No incision infection, axillary nerve injury,loosening screw, plate breakage, shoulder joint dislocation and humeral head osteonecrosis were occurred. According to Neer evaluation of shoulder's function, total score was 88.60 ± 5.12, and 30 cases got excellent results, 7 cases good, 7 cases moderate and 2 cases poor. CONCLUSION: For osteoporotic proximal humeral fractures with rotator cuff tear in elderly patients' plate with rivet repair at stage I is an effective stable method, and provide advantages for earlier exercise of shoulder joint, then receive good clinical effects in further.


Assuntos
Lesões do Manguito Rotador , Fraturas do Ombro/cirurgia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Fraturas do Ombro/diagnóstico
17.
PLoS One ; 9(7): e80069, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24991811

RESUMO

BACKGROUND: After being polio free for more than 10 years, an outbreak following importation of wild poliovirus (WPV) was confirmed in Xinjiang Uygur Autonomous Region, China, in 2011. METHODS: A cross-sectional study was conducted prior to supplementary immunization activities (SIAs), immediately after the confirmation of the WPV outbreak. In selected prefectures, participants aged ≤ 60 years old who visited hospitals at county-level or above to have their blood drawn for reasons not related to the study, were invited to participate in our study. Antibody titers ≥ 8 were considered positive. RESULTS: Among the 2,611 participants enrolled, 2,253 (86.3%), 2,283 (87.4%), and 1,989 (76.2%) were seropositive to P1, P2 and P3 respectively, and 1744 (66.8%) participants were seropositive to all the three serotypes. Lower antibody seropositivities and geometric mean titers were observed in children <1 year of age and in adults aged 15-39 years. CONCLUSION: Serosurveys to estimate population immunity in districts at high risk of polio importation might be useful to gauge underlying population immunity gaps to polio and possibly to guide preparedness and response planning. Consideration should be given to older children and adults during polio risk assessment planning and outbreak response.


Assuntos
Anticorpos Antivirais/sangue , Surtos de Doenças , Poliomielite/sangue , Poliomielite/epidemiologia , Poliovirus , Adolescente , Adulto , Criança , Pré-Escolar , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Lactente , Masculino
18.
Vaccine ; 31 Suppl 9: J29-35, 2013 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-24331017

RESUMO

OBJECTIVE: In order to measure hepatitis B coverage and progress in equality with respect to protection against hepatitis B in poverty-affected areas funded by the Global Alliance on Vaccine and Immunization project funded in poverty-affected counties. METHODS: We reviewed routinely reported coverage data and conducted a national stratified, validation, cross-sectional survey in October 2010, according to WHO recommended sampling method. First, we stratified China into three regions (Eastern, Central and Western) based on economic criteria. Second, in each region, we selected eight counties with a probability proportional to population size. Third, in each selected county, we selected (a) 10 townships at random among the list of townships of the county. RESULTS: We visited 244 townships as part of the final evaluation (71 in the East, 86 in the Center and 87 in the West). Overall, in these 244 townships, surveyed TBD coverage increased from 60% in 2002 to 91% in 2009 and surveyed three dose of hepatitis B vaccine coverage increased from 71% in 2002 to 93% in 2009. Overall, in the GAVI supported areas, the HepB3/DTP3 ratio increased from 57% in 2002 to 94% in 2009. CONCLUSION: Pro-poor GAVI approach was an effective way to reduce inequity among children through provision of free vaccination. When vaccine and AD syringes were provided for free, they closed the gap between Eastern and Western regions and between the rich and the poor.


Assuntos
Acessibilidade aos Serviços de Saúde , Vacinas contra Hepatite B/administração & dosagem , Hepatite B/prevenção & controle , Fatores Socioeconômicos , Vacinação/estatística & dados numéricos , China/epidemiologia , Estudos Transversais , Pesquisa sobre Serviços de Saúde , Hepatite B/epidemiologia , Humanos , Lactente , Recém-Nascido
19.
Vaccine ; 31 Suppl 9: J36-42, 2013 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-24331019

RESUMO

BACKGROUND: Mother to Child Transmission (MTCT) has remained a leading cause of HBV infection in China, accounting for 40% of total infections. Providing hepatitis B vaccine (HepB) to all infants within 24h of birth (Timely Birth Dose, TBD), and subsequent completion of at least 3 vaccine doses is key to preventing perinatal HBV infection. In 2002, with the financial support of the Global Alliance on Vaccine and Immunization (GAVI) targeted to Western region and 223 poverty-affected counties in Central region, hepatitis B vaccine was provided for free. In 2010, we evaluated the China GAVI project in terms of its activities to prevent perinatal infections. OBJECTIVE: The objectives of the evaluation were to (1) measure achievements in the China GAVI project in terms of TBD coverage, and (2) describe practices for HBsAg screening of pregnant women and HBIG use outside the GAVI China project. METHODS: We used the methods recommended by WHO to select a cluster sample of health care facilities for the purpose of an injection safety assessment. We stratified China into three regions based on economic criteria, and selected eight counties with a probability proportional to population size in each region. In each selected county, we selected (a) 10 townships at random among the list of townships of the county and (b) the one county level hospital. In each hospital, we abstracted 2002 through 2009 records to collect information regarding birth cohorts, hospitals deliveries, vaccine management, hepatitis B vaccination delivery, HBsAg screening practices and results, and HBIG administration. In addition, in all hospitals, we abstracted records regarding the delivery of TBD. RESULTS: We visited 244 facilities in the three regions, including 24 county hospitals and 220 township hospitals. We reviewed 837,409 birth summary records, 699,249 for infants born at county or township hospitals. Hospital delivery rates increased from 58% in 2002 to 93% in 2009. Surveyed TBD coverage increased from 60% in 2002 to 91% in 2009 (+31%). Surveyed TBD coverage among children born in hospitals increased from 73% in 2002 to 98% in 2009. Between 2002 and 2009, the proportion of pregnant women screened for HBsAg increased from 64% in 2002 to 85% in 2009. In 2009, the proportion of infants born to women screened and found to be HBsAg positive who did not receive any immunization within 24h after birth ranged from 0% to 0.7% across regions. CONCLUSIONS: Increased availability of hepatitis B vaccine, along with efforts to improve hospital deliveries, increased TBD coverage in China. This decreased perinatal HBV transmission and will reduce disease burden in the future. Screening for HBsAg to guide HBIG administration has begun, but with heterogeneous immuno-prophylaxis practices and a poor system for follow up.


Assuntos
Controle de Doenças Transmissíveis/métodos , Controle de Doenças Transmissíveis/organização & administração , Hepatite B/prevenção & controle , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Adulto , China/epidemiologia , Feminino , Política de Saúde , Pesquisa sobre Serviços de Saúde , Hepatite B/epidemiologia , Anticorpos Anti-Hepatite B/administração & dosagem , Anticorpos Anti-Hepatite B/imunologia , Vacinas contra Hepatite B/administração & dosagem , Vacinas contra Hepatite B/imunologia , Humanos , Recém-Nascido , Masculino , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia
20.
Vaccine ; 31 Suppl 9: J43-8, 2013 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-24331020

RESUMO

OBJECTIVE: The study objectives were to evaluate injection practices in China in the post GAVI project era and provide guidance for policy makers to update national standards for injection practices and further improve vaccination services. METHODS: We conducted a national stratified, cross-sectional survey in October 2010, according to WHO recommended sampling methods. First, we stratified China into three regions (Eastern, Central and Western) based on economic criteria. Second, in each region, we selected eight counties with a probability proportional to population size. Third, in each selected county, we selected (a) 10 townships at random among the list of townships of the county and (b) the one county level hospital. RESULTS: With respect to the risk to the patient, we never observed open injection equipment lying around or needles left in the septum of multi-dose vials. We never observed sterilizable injection devices syringes in any of the facilities. The proportion of facilities using sharps containers was highest in the East (85%), intermediate in the West (79%) and lowest in the Central region (56%). In 2009, auto-disable syringes and safety boxes were used in 78% and 79% facilities in GAVI supported areas of the Western region, respectively. Only one facility presented evidence of attempts to re-sterilize disposable injection equipment in the Eastern region. CONCLUSIONS: Use of AD syringe and sharps containers increased in vaccination services in China, especially in GAVI supported areas, leading to sustainable progress in terms of elimination of reuse of injection devices. However, risk to patients still existed, including persisting use of standard disposable syringes and attempts to re-use disposable devices.


Assuntos
Injeções/efeitos adversos , Vacinação/efeitos adversos , Vacinas/administração & dosagem , Vacinas/efeitos adversos , China , Estudos Transversais , Pesquisa sobre Serviços de Saúde , Humanos
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