Antibiotic residues in foods do not only affect consumers and public health but also affect the l... more Antibiotic residues in foods do not only affect consumers and public health but also affect the livestock industry. We studied the prevalence and concentration of Tetracycline and Fluoroquinolones groups in pork in Hung Yen. A total of 160 pork samples were collected and analyzed using HPLC and ELISA techniques. Results showed that 13/160 (12,31%) samples were positive to Tetracycline group, while Fluoroquinolones group was not found. The residual prevalence of Tetracycline, Oxytetracycline and Chlotetracycline were 3,75, 2,5 and 1,88%, respectively. An average residue concentration of Tetracycline group in pork was 133,72 (50,25-382,9) µg/kg. Compared with the maximum residual limits, two samples exceeded permissible standards of Vietnam and 6 samples exceeded the permitted level of the FAO/WHO and the European Food Safety Authority (EFSA). These findings underlines the situation and trends of antibiotic residues in Hung Yen in particular and in Vietnam in general. Therefore, the monitoring and management of safe and properly using antibiotics in animal husbandry and veterinary needs to be improved
Canadian Journal of Infectious Diseases and Medical Microbiology, 2013
AIM: A population-based study was conducted over a two-year period in the Perth District (PD) and... more AIM: A population-based study was conducted over a two-year period in the Perth District (PD) and Wellington-Dufferin-Guelph (WDG) health units in Ontario to document antimicrobial resistance and antimicrobial use associated with clinical cases of laboratory-confirmed campylobacteriosis.METHODS: Etest (bioMérieux SA, France) was used to determine the minimum inhibitory concentration of amoxicillin/clavulanic acid, ampicillin, chloramphenicol, ciprofloxacin (CIP), clindamycin, erythromycin (ERY), gentamicin, nalidixic acid and tetracycline. Data regarding antimicrobial use were collected from 250 cases.RESULTS: Of the 250 cases, 165 (65.7%) reported staying home or being hospitalized due to campylobacteriosis. Fifty-four per cent of cases (135 of 249) reported taking antimicrobials to treat campylobacteriosis. In 115 cases (51.1%), fecal culture results were not used for treatment decisions because they were not available before the initiation of antimicrobial treatment and/or they w...
Background: We sought to employ a One Health approach in examining live bird markets in northern ... more Background: We sought to employ a One Health approach in examining live bird markets in northern Vietnam for evidence of avian influenza A viruses. Methods: Environmental, animal, and animal worker specimens were collected from four live bird markets (LBMs) across provinces (
In North and Central Vietnam it is common among farmers to use excreta from the family double vau... more In North and Central Vietnam it is common among farmers to use excreta from the family double vault composting latrine (DVC) as fertilizer in the fields. The official Vietnamese health guidelines stipulate a six-month period of composting before applying excreta to two of their three annual crops. However, farmers in this region cannot afford to follow these guidelines and this paper presents the reasons why. In their efforts to ensure optimal hygienic conditions, by providing a guideline, the Vietnamese health authorities have not put sufficient attention to the ‘excreta economy’ in relation to farmers’ livelihoods. The free fertilizer in the household DVC represents a value of approximately US$ 15.5 per year - or the equivalent of 15 percent of the annual household income for the poorest 20 percent of farmers. For this reason, the economic benefits derived from free fertilizer outweigh the hygiene message for most Vietnamese farmers. Even at national level the excreta economy has ...
Research the operation of biogas plant in 451 households in three communes of Hanam province in 2... more Research the operation of biogas plant in 451 households in three communes of Hanam province in 2014. Field survey had interviewed farmers about the operation using household biogas plant. Biogas wastewater samples were collected in tank pressure of biogas plant to test the hygiene indicators. The study results showed that the proportion of households, that use pig manure, poultry manure and human excrement for biogas loaded were 90.2%, 29.7% and 80.3%, respectively. Biogas waste water was discharged into drains directly and commune lakes shared that were 66.5% and 12.9%, respectively. The chemical and microbiological index of wastes was reduced by biogas treatment. However, the rate of biogas sewage had detected Salmonella, Giardia, and Cryptosporidium that was from 34.7 to 56.0%. E. coli concentration in the biogas wastewater of tank pressure has exceeded the WHO recommendation that are applied for animal wastewater using in agriculture. The people have used protection when exposed to sewage of biogas plant. However, protection using are not comprehensive
Cryptosporidium and Giardia are two water- and foodborne protozoan parasites that can cause diarr... more Cryptosporidium and Giardia are two water- and foodborne protozoan parasites that can cause diarrheal diseases. Poor microbial quality, sanitation conditions, and hygiene practices at exposure to biogas wastewater are important risk factors for human and animal infection. This study highlights the presence and level of both parasites in the environment in relation to biogas waste reuse in Vietnam. A total of 239 samples were collected from different types of samples in the studied districts in Bac Giang province in 2020 via direct immunofluorescent detection to study the occurrence of Cryptosporidium spp. and Giardia spp. (oo)cysts. Among the samples, Cryptosporidium was found in 19 (7.9%) with concentration from 1.104 to 3.105 oocysts/100 mL, while Giardia in 40 (16.7%) with concentration from 1.104 to 2.106 cysts/100 mL, respectively. In detail, the results show that the percentages of positive detection of Cryptosporidium spp. and Giardia spp. in influent, effluent, sewage canal,...
Foodborne illness is a difficult public health burden to measure, with accurate incidence data us... more Foodborne illness is a difficult public health burden to measure, with accurate incidence data usually evading disease surveillance systems. Yet, the global scope of foodborne disease and its impacts on socioeconomic development make it an important health risk to address, particularly in low- and middle-income countries. In Vietnam, rapid development has seen large-scale commercial operations rise to coexist amongst traditional value chains in the food landscape, most of which operates outside of a domestic food safety network. Rapid socioeconomic development has also seen an increase in meat consumption, with pork being the most consumed meat product nationally. Expanding pork value chains, and the increasing diversity of actors within them, facilitates the growth and propagation of hazards which are passed onto Vietnamese consumers. In order to guide illness prevention and governance efforts, this review was conducted to examine health risks associated with pork consumption in Vi...
This study assesses the risk of exposure to hazardous chemical residues in pork meat, liver, and ... more This study assesses the risk of exposure to hazardous chemical residues in pork meat, liver, and kidney collected at wet markets in Nghe An and Hung Yen provinces and discusses health impact implication. 514 pig feed, kidney, liver, and pork samples were pooled and qualitatively and quantitatively analyzed for tetracyclines, fluoroquinolones, sulphonamide, chloramphenicol, β-agonists, and heavy metals. We compare the results with current regulations on chemical residues and discuss health implications. Legal antibiotics were found in feed. Tetracycline and fluoroquinolones were not present in pork, but 11% samples were positive with sulfamethazine above maximum residue limits (MRL); 11% of packaged feed and 4% of pork pooled samples were positive for chloramphenicol, a banned substance; two feed, two liver, and one pork samples were positive for β-agonists but did not exceed current MRL; 28% of pooled samples had lead, but all were below MRL; and all samples were negative for cadmium and arsenic. Thus, the health risks due to chemical hazards in pork in Hung Yen and Nghe An seemed not as serious as what were recently communicated to the public on the mass media. There is potential exposure to sulphonamide, chloramphenicol, and β-agonists from pork. Risk communication needs to focus on banned chemicals, while informing the public about the minimal risks associated with heavy metals.
The Southeast Asian Journal of Tropical Medicine and Public Health, Apr 1, 2008
Vietnamese farmers' health-risk awareness, knowledge, and practices related to their use of waste... more Vietnamese farmers' health-risk awareness, knowledge, and practices related to their use of wastewater and human excreta was investigated in an anthropological study by a multidisciplinary team in peri-urban Hanoi and Nghe An Province. Farmers identified health risks associated with their use of excreta and wastewater, but they viewed these as unavoidable risks related to production. They perceived the health risks as different for the use of wastewater and human feces. They perceived health risks from wastewater as non-serious because it remained on the skin and only caused skin problems, but they considered health risks from non-composted smelly feces serious because it entered the body through 'polluted' air. Most farmers were more aware of threats to health from 'dirt' entering the domestic environment than of the health risks during their work. The concept of 'dirt' should be separated from understanding of germs, viruses, and parasites so that it is understood that things that carrying health risks cannot always be identified by their 'dirtiness' or smell. Farmers mainly considered hygiene and health as women's issues. Men's responsibility for the health and hygiene of the family should therefore be emphasized.
Environmental health : a global access science source, Jan 16, 2009
For centuries farmers in Vietnam have fertilized their fields with human excreta collected direct... more For centuries farmers in Vietnam have fertilized their fields with human excreta collected directly from their household latrines. Contrary to the official guideline of six-month storage, the households usually only store human excreta for three to four months before use, since this is the length of time that farmers have available to produce fertilizer between two cropping seasons. This study aimed to investigate whether hygienically safe fertilizer could be produced in the latrines within this period of time. By inoculating eggs of the helminth parasite indicator Ascaris suum into heaps of human excreta, a die-off experiment was conducted under conditions similar to those commonly used in Vietnamese latrines. Half a ton of human excreta was divided into five heaps containing increasing concentrations of lime from 0% to 11%. Regardless of the starting pH, which varied from 9.4 to 11.6, a >99% die-off of eggs was obtained after 105 to 117 days of storage for all lime concentratio...
Antibiotic residues in foods do not only affect consumers and public health but also affect the l... more Antibiotic residues in foods do not only affect consumers and public health but also affect the livestock industry. We studied the prevalence and concentration of Tetracycline and Fluoroquinolones groups in pork in Hung Yen. A total of 160 pork samples were collected and analyzed using HPLC and ELISA techniques. Results showed that 13/160 (12,31%) samples were positive to Tetracycline group, while Fluoroquinolones group was not found. The residual prevalence of Tetracycline, Oxytetracycline and Chlotetracycline were 3,75, 2,5 and 1,88%, respectively. An average residue concentration of Tetracycline group in pork was 133,72 (50,25-382,9) µg/kg. Compared with the maximum residual limits, two samples exceeded permissible standards of Vietnam and 6 samples exceeded the permitted level of the FAO/WHO and the European Food Safety Authority (EFSA). These findings underlines the situation and trends of antibiotic residues in Hung Yen in particular and in Vietnam in general. Therefore, the monitoring and management of safe and properly using antibiotics in animal husbandry and veterinary needs to be improved
Canadian Journal of Infectious Diseases and Medical Microbiology, 2013
AIM: A population-based study was conducted over a two-year period in the Perth District (PD) and... more AIM: A population-based study was conducted over a two-year period in the Perth District (PD) and Wellington-Dufferin-Guelph (WDG) health units in Ontario to document antimicrobial resistance and antimicrobial use associated with clinical cases of laboratory-confirmed campylobacteriosis.METHODS: Etest (bioMérieux SA, France) was used to determine the minimum inhibitory concentration of amoxicillin/clavulanic acid, ampicillin, chloramphenicol, ciprofloxacin (CIP), clindamycin, erythromycin (ERY), gentamicin, nalidixic acid and tetracycline. Data regarding antimicrobial use were collected from 250 cases.RESULTS: Of the 250 cases, 165 (65.7%) reported staying home or being hospitalized due to campylobacteriosis. Fifty-four per cent of cases (135 of 249) reported taking antimicrobials to treat campylobacteriosis. In 115 cases (51.1%), fecal culture results were not used for treatment decisions because they were not available before the initiation of antimicrobial treatment and/or they w...
Background: We sought to employ a One Health approach in examining live bird markets in northern ... more Background: We sought to employ a One Health approach in examining live bird markets in northern Vietnam for evidence of avian influenza A viruses. Methods: Environmental, animal, and animal worker specimens were collected from four live bird markets (LBMs) across provinces (
In North and Central Vietnam it is common among farmers to use excreta from the family double vau... more In North and Central Vietnam it is common among farmers to use excreta from the family double vault composting latrine (DVC) as fertilizer in the fields. The official Vietnamese health guidelines stipulate a six-month period of composting before applying excreta to two of their three annual crops. However, farmers in this region cannot afford to follow these guidelines and this paper presents the reasons why. In their efforts to ensure optimal hygienic conditions, by providing a guideline, the Vietnamese health authorities have not put sufficient attention to the ‘excreta economy’ in relation to farmers’ livelihoods. The free fertilizer in the household DVC represents a value of approximately US$ 15.5 per year - or the equivalent of 15 percent of the annual household income for the poorest 20 percent of farmers. For this reason, the economic benefits derived from free fertilizer outweigh the hygiene message for most Vietnamese farmers. Even at national level the excreta economy has ...
Research the operation of biogas plant in 451 households in three communes of Hanam province in 2... more Research the operation of biogas plant in 451 households in three communes of Hanam province in 2014. Field survey had interviewed farmers about the operation using household biogas plant. Biogas wastewater samples were collected in tank pressure of biogas plant to test the hygiene indicators. The study results showed that the proportion of households, that use pig manure, poultry manure and human excrement for biogas loaded were 90.2%, 29.7% and 80.3%, respectively. Biogas waste water was discharged into drains directly and commune lakes shared that were 66.5% and 12.9%, respectively. The chemical and microbiological index of wastes was reduced by biogas treatment. However, the rate of biogas sewage had detected Salmonella, Giardia, and Cryptosporidium that was from 34.7 to 56.0%. E. coli concentration in the biogas wastewater of tank pressure has exceeded the WHO recommendation that are applied for animal wastewater using in agriculture. The people have used protection when exposed to sewage of biogas plant. However, protection using are not comprehensive
Cryptosporidium and Giardia are two water- and foodborne protozoan parasites that can cause diarr... more Cryptosporidium and Giardia are two water- and foodborne protozoan parasites that can cause diarrheal diseases. Poor microbial quality, sanitation conditions, and hygiene practices at exposure to biogas wastewater are important risk factors for human and animal infection. This study highlights the presence and level of both parasites in the environment in relation to biogas waste reuse in Vietnam. A total of 239 samples were collected from different types of samples in the studied districts in Bac Giang province in 2020 via direct immunofluorescent detection to study the occurrence of Cryptosporidium spp. and Giardia spp. (oo)cysts. Among the samples, Cryptosporidium was found in 19 (7.9%) with concentration from 1.104 to 3.105 oocysts/100 mL, while Giardia in 40 (16.7%) with concentration from 1.104 to 2.106 cysts/100 mL, respectively. In detail, the results show that the percentages of positive detection of Cryptosporidium spp. and Giardia spp. in influent, effluent, sewage canal,...
Foodborne illness is a difficult public health burden to measure, with accurate incidence data us... more Foodborne illness is a difficult public health burden to measure, with accurate incidence data usually evading disease surveillance systems. Yet, the global scope of foodborne disease and its impacts on socioeconomic development make it an important health risk to address, particularly in low- and middle-income countries. In Vietnam, rapid development has seen large-scale commercial operations rise to coexist amongst traditional value chains in the food landscape, most of which operates outside of a domestic food safety network. Rapid socioeconomic development has also seen an increase in meat consumption, with pork being the most consumed meat product nationally. Expanding pork value chains, and the increasing diversity of actors within them, facilitates the growth and propagation of hazards which are passed onto Vietnamese consumers. In order to guide illness prevention and governance efforts, this review was conducted to examine health risks associated with pork consumption in Vi...
This study assesses the risk of exposure to hazardous chemical residues in pork meat, liver, and ... more This study assesses the risk of exposure to hazardous chemical residues in pork meat, liver, and kidney collected at wet markets in Nghe An and Hung Yen provinces and discusses health impact implication. 514 pig feed, kidney, liver, and pork samples were pooled and qualitatively and quantitatively analyzed for tetracyclines, fluoroquinolones, sulphonamide, chloramphenicol, β-agonists, and heavy metals. We compare the results with current regulations on chemical residues and discuss health implications. Legal antibiotics were found in feed. Tetracycline and fluoroquinolones were not present in pork, but 11% samples were positive with sulfamethazine above maximum residue limits (MRL); 11% of packaged feed and 4% of pork pooled samples were positive for chloramphenicol, a banned substance; two feed, two liver, and one pork samples were positive for β-agonists but did not exceed current MRL; 28% of pooled samples had lead, but all were below MRL; and all samples were negative for cadmium and arsenic. Thus, the health risks due to chemical hazards in pork in Hung Yen and Nghe An seemed not as serious as what were recently communicated to the public on the mass media. There is potential exposure to sulphonamide, chloramphenicol, and β-agonists from pork. Risk communication needs to focus on banned chemicals, while informing the public about the minimal risks associated with heavy metals.
The Southeast Asian Journal of Tropical Medicine and Public Health, Apr 1, 2008
Vietnamese farmers' health-risk awareness, knowledge, and practices related to their use of waste... more Vietnamese farmers' health-risk awareness, knowledge, and practices related to their use of wastewater and human excreta was investigated in an anthropological study by a multidisciplinary team in peri-urban Hanoi and Nghe An Province. Farmers identified health risks associated with their use of excreta and wastewater, but they viewed these as unavoidable risks related to production. They perceived the health risks as different for the use of wastewater and human feces. They perceived health risks from wastewater as non-serious because it remained on the skin and only caused skin problems, but they considered health risks from non-composted smelly feces serious because it entered the body through 'polluted' air. Most farmers were more aware of threats to health from 'dirt' entering the domestic environment than of the health risks during their work. The concept of 'dirt' should be separated from understanding of germs, viruses, and parasites so that it is understood that things that carrying health risks cannot always be identified by their 'dirtiness' or smell. Farmers mainly considered hygiene and health as women's issues. Men's responsibility for the health and hygiene of the family should therefore be emphasized.
Environmental health : a global access science source, Jan 16, 2009
For centuries farmers in Vietnam have fertilized their fields with human excreta collected direct... more For centuries farmers in Vietnam have fertilized their fields with human excreta collected directly from their household latrines. Contrary to the official guideline of six-month storage, the households usually only store human excreta for three to four months before use, since this is the length of time that farmers have available to produce fertilizer between two cropping seasons. This study aimed to investigate whether hygienically safe fertilizer could be produced in the latrines within this period of time. By inoculating eggs of the helminth parasite indicator Ascaris suum into heaps of human excreta, a die-off experiment was conducted under conditions similar to those commonly used in Vietnamese latrines. Half a ton of human excreta was divided into five heaps containing increasing concentrations of lime from 0% to 11%. Regardless of the starting pH, which varied from 9.4 to 11.6, a >99% die-off of eggs was obtained after 105 to 117 days of storage for all lime concentratio...
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