Monitoring of Antibiotic Residues in Aquatic Products in Urban and Rural Areas of Vietnam

Antibiotic residues in aquatic products in Vietnam were investigated. A total of 511 fish and shrimp samples were collected from markets in Ho Chi Minh City (HCMC), Thai Binh (TB), and Nha Trang (NT) from July 2013 to October 2015. The samples were extracted with 2% formic acid in acetonitrile and washed with dispersive C18 sorbent. Thirty-two antibiotics were analyzed by LC-MS/MS. Of the 362 samples from HCMC, antibiotic residues were found in 53 samples. Enrofloxacin was commonly detected, at a rate of 10.8%. In contrast, samples from TB and NT were less contaminated: only 1 of 118 analyzed samples showed residues in TB and only 1 of 31 showed residues in NT. These differences were attributed to the local manufacturing/distribution systems. To understand the current status of antibiotic use and prevent adverse effects that may be caused by their overuse, continual monitoring is required.

Antibiotic residue monitoring results for pork, chicken, and beef samples in Vietnam in 2012-2013

A monitoring plan of residual antibiotics in food of animal origin was conducted in Vietnam from 2012 to 2013. Meat samples were collected from slaughterhouses and retail stores in Ho Chi Minh City and Nha Trang. A total of 28 antibiotics were analyzed using a LC-MS/MS screening method. Sulfonamides, fluoroquinolones, and tilmicosin were detected in some of the samples. Sulfaclozine and fluoroquinolones were mainly detected in chicken samples, and sulfamethazine was mainly detected in pork samples. High levels of sulfonamide residues, ranging between 2500 and 2700 μg/kg sulfaclozine and between 1300 and 3600 μg/kg sulfamethazine, were present in two chicken and three pork samples, respectively. Tilmicosin was detected at ranges of 150-450 μg/kg in 10 chicken samples. Positive percentages were 17.3, 8.8, and 7.4% for chicken, pork, and beef, respectively, for an average of 11.9%. The results suggest an appropriate withdrawal period after drug administration had not been observed in some livestock.

Multimorbidity and its social determinants among older people in southern provinces, Vietnam

BACKGROUND

Developing countries are poorly equipped for health issues related to ageing populations making multimorbidity challenging. As in Vietnam the focus tends to be on single conditions. Hence little is known about burden of multimorbidity. This study aimed to examine the prevalence and the determinants of multimorbidity among older people in Southern Vietnam.

METHODS

A cross-sectional study was conducted in two provinces of Southern Vietnam with a sample of 2400 people aged 60 years and older. The presence of chronic disease was ascertained by medical examination done by physicians at commune health stations. Information on social and demographic factors was collected using structured questionnaire. Univariate and multivariable logistic regression analyses were used to examine the factors associated with multimorbidity.

RESULTS

Nearly 40 % of older people had multimorbidity. Currently not working, and healthcare utilisation were associated with higher prevalence of multimorbidity. Living in urban areas and being literate were associated with lower prevalence of multimorbidity.

CONCLUSION

The study found a high burden of multimorbidity among illiterate, especially those living in rural areas. This highlights the need for targeted community based programs aimed at reducing the burden of chronic disease.

Quality of life among people living with hypertension in a rural Vietnam community

Background

To respond to growing prevalence of hypertension in Vietnam, it is critical to have an in-depth understanding about quality of life (QOL) among people living with hypertension and related factors. This study aimed to measure QOL among hypertensive people in a rural community in Vietnam, and its association with socio-demographic characteristics and factors related to treatment.

Methods

This study was conducted in a rural community located 60 km from Ho Chi Minh City. Face-to-face interviews were conducted among 275 hypertensive people aged 50 years and above using WHOQOL-BREF questionnaire. Descriptive statistics were used to examine mean scores of quality of life. Cronbach’s alpha coefficient and Pearson’s correlation coefficient were applied to estimate the internal consistency, and the level of agreement between different domains of WHOQOL-BREF, respectively. Independent T-test and ANOVA test followed by multiple linear regression analyses were used to measure the association between QOL domains and independent variables.

Results

Both overall WHOQOL-BREF and each domain had a good internal consistency, ranging from 0.65 to 0.88. The QOL among hypertensive patients was found moderate in all domains, except for psychological domain that was fairly low (mean = 49.4). Backward multiple linear regressions revealed that being men, married, attainment of higher education, having physical activities at moderate level, and adherence to treatment were positively associated with QOL. However, older age and presence of co-morbidity were negatively associated with QOL.

Conclusion

WHOQOL-BREF is a reliable instrument to measure QOL among hypertensive patients. The results revealed low QOL in psychological domain and inequality in QOL across socio-demographic characteristics. Given the results, encouraging physical activities and strengthening treatment adherence should be considered to improve QOL of hypertensive people, especially for psychological aspect. Actions to improve QOL among hypertensive patients targeted towards women, lower educated and unmarried patients are needed in the setting.

An outbreak of food-borne salmonellosis linked to a bread takeaway shop in Ben Tre City, Vietnam

OBJECTIVES

To identify the vehicle, source, and causative agent of a community-wide food-borne outbreak of gastroenteritis.

METHODS

We conducted a case-control study. Cases were city residents diagnosed with gastroenteritis and hospitalized in Ben Tre City from 22 to 25 May 2013; 41 cases were selected randomly from a list of hospitalized patients. Controls were age- and gender-matched healthy neighbours of cases. Participants were interviewed using a standard questionnaire. Samples from patients and food were tested at reference laboratories. We used conditional logistic regression to calculate matched odds ratios (mORs) for the association of gastroenteritis with food items consumed.

RESULTS

Of the 41 cases enrolled in the study, 61% were males and the median age was 33 years; cases resided in 12 wards of the City. Of 13 food items consumed by the cases, only stuffed bread was significantly associated with gastroenteritis (mOR 21.3, 95% confidence interval 6.3-71.8). Among the 29 cases who ate stuffed bread, the median time to illness onset was 9h. Patient stool samples and bread samples were positive for Salmonella species.

CONCLUSIONS

Stuffed bread was the likely vehicle of the outbreak. The laboratory testing capacity for serotypes of Salmonella should be strengthened in Vietnam. Food-handler training in basic food safety measures should be improved.

Acute allergic reactions in Vietnamese children after drinking a new milk product

In early October 2009, pediatricians in hospitals in Ho Chi Minh City (HCMC) reported an unusual increase in the number of children presenting with an acute onset of itchy rash and some with breathing difficulties shortly after drinking milk products. The pediatricians considered the illness to be an allergic reaction to milk. The objective of our investigation was to identify the cause of this acute illness. Following early case reports, all hospitals in HCMC were requested to report cases of this illness. Parents were advised to take children with symptoms to a hospital immediately. A case-series was conducted to generate hypotheses on the possible causes of the illness and was followed by a case-control study to test the hypothesis. Parents of all cases and controls were interviewed face-to-face. The association between food items and the allergy was tested using conditional logistics regression. From 9 to 28 October 2009, 19 cases fulfilled the case definition, and 16 of the 17 cases included in the study had consumed milk supplemented with galacto-oligosaccharides (GOS) shortly before the onset of illness. Fifty age-matched, neighborhood controls were enrolled into the case control study. Of the 30 food items consumed by study participants in the preceding 24 h, only the odds ratio (OR) of milk supplemented with GOS was statistically significant: OR=34.0 (95% CI=3.9, 294.8). Laboratory tests of this milk product did not reveal any unusual properties, chemicals, or other toxic substances. This is the first report of an acute allergic reaction to fresh milk supplemented with GOS. However, the specific allergen in this product was not identified. Further cases were not reported once this product was withdrawn from sale. Vietnam's food safety authorities should expand laboratory capacity to detect allergens in food products.

A cluster of cholera among patients in a Vietnamese district hospital in 2010

On July 20, 2010, three cases of cholera were reported from a district hospital in Ca Mau province, Vietnam. We investigated the likely source and mode of transmission of the outbreak. All hospitals in the province were requested to notify cases of acute watery diarrhoea. Epidemiological, clinical, and laboratory data were collected. Between July 12 and 22, seven cases with positive culture for Vibrio cholera were identified. Six cases were epidemiologically linked to the index case. Basic infection control practices were not in place at the hospital. Clinicians and public health staff should consider the possibility of nosocomial cholera transmission even in non-endemic areas.

Phamacokinetics of a single oral dose of dihydroartemisinin in Vietnamese healthy volunteers

Pharmacokinetics of a 240 mg single dose of oral dihydroartemisinin (DHA) was investigated in 8 healthy (5 males, 3 females) Vietnamese volunteers. Plasma concentrations were measured by high-performance liquid chromatography with electrochemical detection in the reductive mode. The concentration time profile of DHA was fitted with one-compartment model with a lag time. Pharmacokinetics of DHA is comparable between males and females even when adjusted with dosage. The median (range) values of pooled pharmacokinetics of oral DHA were: t(lag) 0.41 (0.09-0.78) hours, t(1/2z) 0.58 (0.17-1.43) hours, t(max) 1.6 (1.1-2.2) hours, Cmax 466 (128-787) ng/ml. Cmax/dosage 97.7 (27.2-124.6) ng/ml, t(1/2z) 2.0 (1.5-3.4) hours, AUC 1867 (420-3535) ng x h/ml, AUC/dosage 364.3 (89.3-559.7) ng x h/ml/dosage, Cl/f 45.8 (30.0-190.0) ml/min/kg, Vz/f 8.0 (5.5-29.9) l/kg. Interindividual variation was large, the coefficients of variation (CV) were 47.8% and 45.3% respectively to AUC and Cmax. The t(max) of DHA formulation was comparable with that of DHA metabolite of artemisinin derivatives. The t(1/2z) was longer and shorter than that of DHA metabolites of oral formulations of artesunate and artemether, respectively. For monotherapeutic regimen(s) of DHA, dosing frequency of at least twice a day is suggested. Combined regimen(s) of DHA with other potent, long half-life antimalarials may also be an alternative approach.