RESUMO
Burkholderia pseudomallei is a soil-dwelling bacterium and the cause of melioidosis, which kills an estimated 89,000 people per year worldwide. Agricultural workers are at high risk of infection due to repeated exposure to the bacterium. Little is known about the soil physicochemical properties associated with the presence or absence of the organism. Here, we evaluated the soil physicochemical properties and presence of B. pseudomallei in 6,100 soil samples collected from 61 rice fields in Thailand. The presence of B. pseudomallei was negatively associated with the proportion of clay, proportion of moisture, level of salinity, percentage of organic matter, presence of cadmium, and nutrient levels (phosphorus, potassium, calcium, magnesium, and iron). The presence of B. pseudomallei was not associated with the level of soil acidity (P = 0.54). In a multivariable logistic regression model, the presence of B. pseudomallei was negatively associated with the percentage of organic matter (odds ratio [OR], 0.06; 95% confidence interval [CI], 0.01 to 0.47; P = 0.007), level of salinity (OR, 0.06; 95% CI, 0.01 to 0.74; P = 0.03), and percentage of soil moisture (OR, 0.81; 95% CI, 0.66 to 1.00; P = 0.05). Our study suggests that B. pseudomallei thrives in rice fields that are nutrient depleted. Some agricultural practices result in a decline in soil nutrients, which may impact the presence and amount of B. pseudomallei bacteria in affected areas. IMPORTANCE: Burkholderia pseudomallei is an environmental Gram-negative bacillus and the cause of melioidosis. Humans acquire the disease following skin inoculation, inhalation, or ingestion of the bacterium in the environment. The presence of B. pseudomallei in soil defines geographic regions where humans and livestock are at risk of melioidosis, yet little is known about the soil properties associated with the presence of the organism. We evaluated the soil properties and presence of B. pseudomallei in 61 rice fields in East, Central, and Northeast Thailand. We demonstrated that the organism was more commonly found in soils with lower levels of organic matter and nutrients, including phosphorus, potassium, calcium, magnesium, and iron. We also demonstrated that crop residue burning after harvest, which can reduce soil nutrients, was not uncommon. Some agricultural practices result in a decline in soil nutrients, which may impact the presence and amount of B. pseudomallei bacteria in affected areas.
Assuntos
Burkholderia pseudomallei/isolamento & purificação , Microbiologia do Solo , Solo/química , Burkholderia pseudomallei/classificação , Burkholderia pseudomallei/genética , Meio Ambiente , Oryza/crescimento & desenvolvimento , Salinidade , TailândiaRESUMO
The maintenance of Leptospira species in liquid or semisolid medium is time-consuming and at risk of contamination due to the needs of routine subculture and dark field microscopy. Using Leptospira Vanaporn Wuthiekanun (LVW) agar, we maintained 100 pathogenic Leptospira isolates for 12 months without the need for subculture and confirmed the viability of all isolates by the naked eye.
Assuntos
Técnicas Bacteriológicas/métodos , Meios de Cultura/química , Leptospira/fisiologia , Preservação Biológica/métodos , Ágar , Humanos , Viabilidade Microbiana , Fatores de TempoRESUMO
Introduction: Emerging infectious diseases pose a threat to public health and the economy, especially in developing countries. Southeast Asian veterinary laboratories handle numerous high-risk pathogens, making pathogen accountability crucial for safe handling and storage. Methods: Thirteen veterinary laboratories in Cambodia (n = 1), Lao People's Democratic Republic (n = 1), and Thailand (n = 11) participated in a study conducted between 2019 and 2020. Data were collected using a questionnaire, group discussions, and interviews. Conclusion: Significant gaps in biosecurity and biorepository management were recognized and discussed in the context of regional biosafety and biosecurity. Laboratories could use the findings and recommendations of the study to develop or improve their pathogen inventory and biosecurity systems. Governments play a significant role in setting standards and regulations and providing necessary support for laboratories to maintain inventory controls sustainably and have a very important role to play in ensuring biosafety and biosecurity compliance.