An Occupational Risk Survey of a Refractory Brick Company in Ha Noi,Viet Nam

Abstract

Viet Nam has an increasing need for building materials, including refractory bricks. Little is known regarding the occupational hazards incurred in brick manufacturing. To determine the occupational health hazards posed by a refractory brick operation in Ha Noi, Viet Nam, a cross-sectional occupational risk survey was conducted, focusing on respirable dust hazards. It included an industrial hygiene walk-through and gravimetric dust analysis. Noise, heat, lack of head protection, and dust exposure were hazards identified at the brick-manufacturing site. Respiratory protection involved a three-layer cloth mask that had not been tested for efficacy. Silica dust exposure levels exceeded the Vietnamese permissible exposure level by almost fivefold based on gravimetric assessment and estimated silica content. This brick manufacturing site contains significant injury and respiratory illness hazards. Further investigations are necessary to begin to develop occupational safety measures at the site.     

Factors of occupational injury: a survey in a chemical company

Chemical industries being the seat of dangerous occurrences frequently resulting in injuries, an occupational injury surveillance study was initiated involving 307 permanent and 419 temporary workers in a chemical company to understand the contribution of different possible factors on injury causation. Risk calculation was undertaken in relation to every individual factor using univariate and multivariate analysis techniques. Workers of lower age were found to be more susceptible to accidents (as evidenced by negative correlation coefficient), though non-significantly. Lower job duration (experience) had a significant impact on injury causation (correlation coefficient -0.5115, p<0.05). Alcohol habit could not show any significant impact but smoking/chewing habit showed significant effect (OR, 7.29: 95% CI, 3.88-9.33) on accident occurrence. Nature of job had no significant impact but nature of employment was found to have considerable effect on the causation of injuries. Temporary nature of employment was at greater risk (OR, 2.51: 95% CI, 1.42-3.77) in comparison to permanent workers.     

Human leptospirosis in the Mekong delta, Viet Nam.

To estimate the seroprevalence of human leptospirosis in the Mekong delta in Viet Nam, an epidemiological survey was conducted in the province of Tien Giang, which is representative of the socioeconomic activities of the region (rice growing and cattle breeding). A cross-sectional study included 35 clusters representing 1400 people randomly selected and aged 15-60 years. Sex, age, occupation, contact with animals, type of water supply, and individual habits were recorded. Leptospiral agglutinins were detected by the microagglutination test, with a battery of 22 live antigens representing the main pathogenic serogroups of Leptospira species and additional local strains. 263 sera (18.8%) gave positive results and 41 (2.9%) had a titre of agglutinins > or = 400, suggesting recent infection. No significant difference was found between females and males. The distribution of seroprevalence was homogeneous throughout the population studied, with the exception of the 15-25 years age group, in which leptospiral antibodies were less frequent. Fifteen serogroups were found, the most prevalent being Bataviae (21.7%), Panama (15.2%), Icterohaemorrhagiae (13.7%) and Australis (8.7%). No significant link between leptospiral seropositivity and professional activities or contacts with animals was found, indicating that leptospirosis in the Mekong delta may be considered as an environmentally linked disease. Leptospirosis is known to be endemic in south-east Asia, and these data demonstrated the high level of circulation of leptospires and the potential importance of leptospiral infections among the rural population in this area.     

Control of malaria: a successful experience from Viet Nam

OBJECTIVE: To follow malaria prospectively in an ethnic minority commune in the south of Viet Nam with high malaria transmission and seasonal fluctuation, during malaria control interventions using insecticide-treated bednets (ITBNs) and early diagnosis and treatment (EDT) of symptomatic patients. METHODS: From 1994 onwards the following interventions were used: distribution of ITBNs to all households with biannual reimpregnation; construction of a health post and appointment of staff trained in microscopic diagnosis and treatment of malaria; regular supply of materials and drugs; annual cross-sectional malaria surveys with treatment of all parasitaemic subjects, and a programme of community involvement and health education. Surveys were held yearly at the end of the rainy season. During the surveys, demographic data were updated. Diagnosis and treatment of malaria were free of charge. Plasmodium falciparum infection was treated with artesunate and P. vivax infection with chloroquine plus primaquine. FINDINGS: The baseline survey in 1994 recorded 716 inhabitants. Of the children under 2 years of age, 37% were parasitaemic; 56% of children aged 2-10 years, and 35% of the remaining population were parasitaemic. P. falciparum accounted for 73-79% of these infections. The respective splenomegaly rates for the above-mentioned age groups were 20%, 56%, and 32%. In 1999, the proportion of parasitaemic subjects was 4%, 7% and 1%, respectively, of which P.falciparum contributed 56%. The splenomegaly rate was 0%, 5% and 2%, respectively. CONCLUSIONS: A combination of ITBNs and EDT, provided free of charge, complemented by annual diagnosis and treatment during malaria surveys and community involvement with health education successfully brought malaria under control. This approach could be applied to other regions in the south of Viet Nam and provides a sound basis for further studies in other areas with different epidemiological patterns of malaria.     

Cost of immunization with a locally produced, oral cholera vaccine in Viet Nam

Policy decisions regarding whether to incorporate new vaccines into routine public health practice in developing countries will depend in part on the costs of vaccine purchase and of vaccine delivery. In March, 1997, a large-scale effectiveness trial of a locally produced, orally administered bivalent vaccine against Vibrio cholerae 01 and 0139 began in Viet Nam. Empirical data obtained from the trial was used to determine the costs of the immunization campaign from the government perspective. The study population, including the children less than one year of age and pregnant women who were ineligible for immunization, was 353926. A total of 289041 persons received two doses of vaccine, and 13340 persons received one dose of vaccine. Two-dose vaccine coverage was 83.4%. The total cost of vaccine delivery during the immunization campaign was $66527. The cost of each dose of vaccine was $0.31. Therefore, the total cost of the immunization campaign was $0.44 per dose administered, and $0.91 per fully immunized person. Attempts to reduce the cost per dose of vaccine (e.g. the use of a monovalent vaccine against serogroup 01) are likely to have a large impact on the cost of future similar immunization campaigns.     

Alcohol use and HIV risk behaviors among rural adolescents in Khanh Hoa Province Viet Nam

Research suggests that youth are consuming more alcohol and at younger ages than in the past. Data also indicate that alcohol consumption is associated with participation in other risk behaviors including aggression and sexual behaviors. As part of a randomized control effectiveness trial for an HIV prevention program, 480 Vietnamese youth (15-20 years old) living in eight rural communes in Khanh Hoa Province were administered a paper and pencil baseline evaluation. The evaluation included items for actual and intended alcohol use, perceptions of peers' alcohol consumption, and attitudinal questions regarding alcohol. The tool included questions on engagement and intention to engage in sexual behaviors. In addition, 96 randomly selected youth participated in qualitative interviews on similar topics. Among the 480 surveyed youth, 29.2% had consumed alcohol. Among those youth, 17.6% reported intoxication in the past 6 months. While young men were significantly more likely to drink than young women (P < 0.00), those young women who did drink were as likely to report intoxication. Alcohol use was significantly associated with engagement in sexual behaviors (P < 0.00) and intention to engage in sexual behaviors (P < 0.02). The qualitative data provided information on the social contexts of drinking behaviors and more in-depth findings regarding associated risk behaviors. With limited information about alcohol consumption among Vietnamese youth, these findings suggest that there is a need for more extensive research on alcohol use and associated risk behaviors among this population, and for targeted alcohol prevention and harm-reduction programs.     

Development of pandemic influenza vaccine production capacity in Viet Nam

The Institute of Vaccines and Medical Biologicals (IVAC), a state-owned vaccine manufacturer, initiated research into avian influenza vaccines in the early 1990 s in response to the threat of a highly pathogenic avian influenza pandemic. Successful results from laboratory studies on A(H5N1) influenza virus attracted seed funds and led to participation in the WHO technology transfer project to enhance influenza vaccine production in developing countries. IVAC's goal is to produce 500,000 doses of inactivated monovalent whole-virion influenza vaccine per year by 2012, and progressively increase capacity to more than 1 million doses to protect essential populations in Viet Nam in the event of an influenza pandemic. The WHO seed grants, supplemented by other international partner support, enabled IVAC to build in a very short time an influenza vaccine manufacturing plant under Good Manufacturing Practice and relevant biosafety standards, a waste treatment system and a dedicated chicken farm for high-quality eggs. Much of the equipment and instrumentation required for vaccine production has been installed and tested for functional operation. Staff have been trained on site and at specialized courses which provided comprehensive manuals on egg-based manufacturing processes and biosafety. Following process validation, clinical trials will start in 2011 and the first domestic influenza vaccine doses are expected in 2012.     

The use of a computerized database to monitor vaccine safety in Viet Nam

Health information systems to monitor vaccine safety are used in industrialized countries to detect adverse medical events related to vaccinations or to prove the safety of vaccines. There are no such information systems in the developing world, but they are urgently needed. A large linked database for the monitoring of vaccine-related adverse events has been established in Khanh Hoa province, Viet Nam. Data collected during the first 2 years of surveillance, a period which included a mass measles vaccination campaign, were used to evaluate the system. For this purpose the discharge diagnoses of individuals admitted to polyclinics and hospitals were coded according to the International Classification of Diseases (ICD)-10 guidelines and linked in a dynamic population database with vaccination histories. A case-series analysis was applied to the cohort of children vaccinated during the mass measles vaccination campaign. The study recorded 107,022 immunizations in a catchment area with a population of 357,458 and confirmed vaccine coverage of 87% or higher for completed routine childhood vaccinations. The measles vaccination campaign immunized at least 86% of the targeted children aged 9 months to 10 years. No medical event was detected significantly more frequently during the 14 days after measles vaccination than before it. The experience in Viet Nam confirmed the safety of a measles vaccination campaign and shows that it is feasible to establish health information systems such as a large linked database which can provide reliable data in a developing country for a modest increase in use of resources.     

Incidence of postpartum infection after vaginal delivery in Viet Nam

This study assessed the incidence of postpartum infection which is rarely clinically evaluated and is probably underestimated in developing countries. This prospective study identified infection after vaginal delivery by clinical and laboratory examinations prior to discharge from hospital and again at six weeks postpartum in Ho Chi Minh City, Viet Nam. Textbook definitions, physicians' diagnoses, symptomatic and verbal autopsy definitions were used for classifying infection. Logistic regression was used for determining associations of postpartum infection with socioeconomic and reproductive characteristics. In total, 978 consecutive, eligible consenting women were followed up at 42+/-7 (range 2-45) days postpartum (not associated with incidence). Ninety-eight percent took 'prophylactic' antibiotics. The most conservative estimate of the incidence of postpartum infection was 1.7%. The incidence of serious infection was 0.5%, but increased to 4.6% when verbal autopsy and symptomatic definitions were used. Postpartum infection, particularly serious infection, is greatly underestimated. Just preventing or treating infection could have a substantial impact on reducing maternal mortality in developing countries.     

越南家用杀虫剂产品的历史、现状及法律要求

越南是一发展中国家，近几年来，在卫生及家用杀虫剂方面的使用量增长迅速，我们迫切需要安全有效的产品，来提高生活质量。因此，在我国对杀虫剂进行管理与控制，并制定相应法规，就显得非常重要。     

Acceptability and accessibility of a Shigellosis vaccine in Nha Trang city of Viet Nam

The acceptability and accessibility of a hypothetical Shigella vaccination campaign was explored. A household survey was conducted with 539 randomly-selected residents of six communes in Nha Trang city of Viet Nam. Four categories of acceptability, such as refusers, low acceptors, acceptors, and high acceptors, were established, Refusers were significantly more likely to be elderly women and were less likely to know the purpose of vaccinations. Low acceptors tended to be male, elderly, and live in urban areas. Low acceptors perceived the disease as less serious and themselves as less vulnerable than acceptors and high acceptors. In terms of accessing vaccination, the commune health centre workers and commune leaders were the preferred sources of information and commune health centres the preferred location for vaccination. Direct verbal information from healthcare providers and audio-visual media were preferred to written information. The respondents expressed a desire for knowledge about the side-effects and efficacy of the vaccine. These findings are significant for targeting specific messages about shigellosis and vaccination to different populations and maximizing informed participation in public-health campaigns.     

Probabilistic assessment of chlorpyrifos exposure to rice farmers in Viet Nam

Chlorpyrifos is the most common organophosphate compound registered for agricultural use in Vietnam. The aim of this study was to evaluate chlorpyrifos exposure to rice farmers in Vietnam, using a probabilistic approach. Urine samples on a 24-h basis were collected from farmers before and post application of pesticide. Samples were analysed for 3,5,6-trichloro-2-pyridinol (TCP), the major urinary metabolite of chlorpyrifos, using an enzymatic pre-treatment for extraction and HPLC-MS/MS. Absorbed daily doses (ADD) of chlorpyrifos for farmers were subsequently estimated from the urinary TCP levels. The baseline and post-application exposure levels were evaluated at the 5th, 50th, and 95th percentile representing low, medium and high-exposure groups in the population. Regression analysis was applied to examine the association between exposure level and factors. The baseline exposure level, which ranged from 0.03 to 1.98 μg/kg/day was below the chronic guidelines recommended by international and national bodies. However, the post-application exposure level, which ranged from 0.35 to 94 μg/kg/day exceeded most of the acute guidelines at the 95th percentile level. Multivariate analysis provided strong evidence for a relationship between post-application exposure level and amount of chlorpyrifos used, as well as body coverage of personal protective equipment.     

Survey of Food-hygiene Practices at Home and Childhood Diarrhoea in Hanoi, Viet Nam

A cross-sectional study was conducted to investigate the potential factors of food-hygiene practices of mothers on the prevalence of diarrhoea among their children. Mothers who had children aged 6 months–5 years were recruited in a hamlet in Viet Nam. The food-hygiene practices included hand-washing, method of washing utensils, separation of utensils for raw and cooked food, and the location where foods were prepared for cooking. A face-to-face interview was conducted, and data on 206 mothers were analyzed. The risk of diarrhoea was significantly higher among children whose mothers prepared food for cooking somewhere other than the table (typically on the ground) compared to children whose mothers prepared food on the table (adjusted odds ratio=2.85, 95% confidence interval 1.11–7.28). The results indicate that food-hygiene practices of mothers, such as avoiding preparing food for cooking on the ground, has a potential impact in preventing diarrhoea among children in Viet Nam.Key words: Cross-sectional studies, Diarrhoea, Diarrhoea, Infantile, Food handling, Hygiene, Knowledge, attitudes, and practice, Viet Nam     

某生物科技有限公司职业病危害因素评价

目的对某生物科技有限公司进行职业病危害现状评价。方法通过职业卫生现场调查、职业病危害因素检测、查阅劳动者职业健康监护和职业卫生管理档案等,对企业作业场所的职业病危害现状进行分析与评价。结果粉尘、氨、甲醇、硫酸、氯化氢（盐酸）、磷酸、二氧化硫、氢氧化钠、氢氧化钾、噪声和高温污染是该厂存在的主要职业病有害因素,检测结果显示接触粉尘（CSTEL：23.67～34.00 mg/m3）、二氧化硫（CSTEL：24.51 mg/m3）、噪声〔86.4～89.6 dB（A）〕、高温（WBGT指数：35℃）的部分岗位检测结果不符合国家职业接触限值的要求,其他毒物的接触岗位检测结果均符合国家职业接触限值的要求。接触有害作业的工人尚未发现与职业有关的异常情况。结论在职业病防治工作上,该厂采取了一定的措施,防尘、毒、噪声设施基本齐全,但在部分岗位仍有超标情况,尚需加强治理。     

Patterns and risk factors of inconsistent condom use among men who have sex with men in Viet Nam: Results from an Internet-based cross-sectional survey

Survey data from men who have sex with men (MSM) in Asian cities indicate drastic increases in HIV prevalence. It is unknown which factors are most important in driving these epidemics. The objective of this study was to identify patterns of condom use among MSM Internet users living in Viet Nam, as well as risk factors associated with inconsistent condom use and non-condom use. A national Internet-based survey of sexual behaviours was administered in 2011. Results showed that 44.9% of MSM reported not using a condom during their last anal sex encounter with a male partner. MSM were less likely to report condom use during anal sex with long-term partners than with casual partners. Twenty-three and a half per cent of MSM surveyed had ever taken an HIV test and received the results. Study findings highlight the urgent need for targeted strategies focused on increasing the rate of consistent condom use during anal sex with male partners among MSM in Viet Nam.