Genotyping Characteristics of Human Fecal Escherichia coli and Their Association with Multidrug Resistance in Miyun District, Beijing.

Objective: To explore the genotyping characteristics of human fecal Escherichia coli( E. coli) and the relationships between antibiotic resistance genes (ARGs) and multidrug resistance (MDR) of E. coli in Miyun District, Beijing, an area with high incidence of infectious diarrheal cases but no related data. Methods: Over a period of 3 years, 94 E. coli strains were isolated from fecal samples collected from Miyun District Hospital, a surveillance hospital of the National Pathogen Identification Network. The antibiotic susceptibility of the isolates was determined by the broth microdilution method. ARGs, multilocus sequence typing (MLST), and polymorphism trees were analyzed using whole-genome sequencing data (WGS). Results: This study revealed that 68.09% of the isolates had MDR, prevalent and distributed in different clades, with a relatively high rate and low pathogenicity. There was no difference in MDR between the diarrheal (49/70) and healthy groups (15/24). Conclusion: We developed a random forest (RF) prediction model of TEM.1 + baeR + mphA + mphB + QnrS1 + AAC.3-IId to identify MDR status, highlighting its potential for early resistance identification. The causes of MDR are likely mobile units transmitting the ARGs. In the future, we will continue to strengthen the monitoring of ARGs and MDR, and increase the number of strains to further verify the accuracy of the MDR markers.

Family socioeconomic position and abnormal birth weight: evidence from a Chinese birth cohort.

BACKGROUND: Birth weight is a strong determinant of infant short- and long-term health outcomes. Family socioeconomic position (SEP) is usually positively associated with birth weight. Whether this association extends to abnormal birth weight or there exists potential mediator is unclear. METHODS: We analyzed data from 14,984 mother-infant dyads from the Born in Guangzhou Cohort Study. We used multivariable logistic regression to assess the associations of a composite family SEP score quartile with macrosomia and low birth weight (LBW), and examined the potential mediation effect of maternal pre-pregnancy body mass index (BMI) using causal mediation analysis. RESULTS: The prevalence of macrosomia and LBW was 2.62% (n = 392) and 4.26% (n = 638). Higher family SEP was associated with a higher risk of macrosomia (OR 1.30, 95% CI 0.93-1.82; OR 1.53, 95% CI 1.11-2.11; and OR 1.59, 95% CI 1.15-2.20 for the 2nd, 3rd, and 4th SEP quartile respectively) and a lower risk of LBW (OR 0.69, 95% CI 0.55-0.86; OR 0.76, 95% CI 0.61-0.94; and OR 0.61, 95% CI 0.48-0.77 for the 2nd, 3rd, and 4th SEP quartile respectively), compared to the 1st SEP quartile. We found that pre-pregnancy BMI did not mediate the associations of SEP with macrosomia and LBW. CONCLUSIONS: Socioeconomic disparities in fetal macrosomia and LBW exist in Southern China. Whether the results can be applied to other populations should be further investigated.