Longitudinal Assessment of Antibiotic Resistance in Fecal Escherichia coli in Tanzanian Children

Am J Trop Med Hyg. 2019 May;100(5):1110-1114. doi: 10.4269/ajtmh.18-0789.


Antibiotic-resistant bacterial infections are a major public health problem, and children in low-resource settings represent a particularly high-risk group. Few data are available on the dynamics of and risk factors for gastrointestinal carriage of antibiotic-resistant bacteria in these vulnerable populations. In this study, we described the antibiotic susceptibility profiles of Escherichia coli isolated from stool specimens collected from children aged 6 to 60 months enrolled in a birth cohort study in Haydom, Tanzania. We estimated the association between sociodemographic risk factors, child illnesses, and antibiotic exposure and E. coli drug resistance. Carriage of antibiotic-resistant E. coli was common starting early in life and did not clearly increase with age. The majority of isolates were resistant to ampicillin (749/837; 89.5%), cefazolin (742/837; 88.6%), and cotrimoxazole (721/837; 86.1%). Resistance to amoxicillin/clavulanate (361/836; 43.2%), ampicillin/sulbactam (178/819; 21.7%), nalidixic acid (131/831; 15.8%), and azithromycin (115/837; 13.7%) was also seen. Only 1.8% (15/837) of the pooled E. coli isolates met the criteria for extended-spectrum beta-lactamase production. High antibiotic use (0.26 additional resistant antibiotic classes; 95% CI: 0.05, 0.47) and high income (0.28 additional resistant antibiotic classes; 95% CI: 0.06, 0.50) were associated with the carriage of antibiotic-resistant E. coli, whereas hospital birth, crowding in the home, improved drinking water and sanitation, and common childhood illnesses were not. In this setting, the carriage of antibiotic-resistant E. coli was common. Other than recent antibiotic exposure and high income, individual risk factors for the acquisition and carriage of resistance could not be identified, suggesting that population-level interventions are needed.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Age Factors
  • Anti-Bacterial Agents / pharmacology*
  • Asymptomatic Infections / epidemiology
  • Child, Preschool
  • Drug Resistance, Multiple, Bacterial*
  • Escherichia coli / drug effects*
  • Escherichia coli / enzymology
  • Escherichia coli Infections / epidemiology
  • Escherichia coli Infections / microbiology
  • Feces / microbiology*
  • Female
  • Humans
  • Infant
  • Longitudinal Studies
  • Male
  • Microbial Sensitivity Tests
  • Risk Factors
  • Socioeconomic Factors
  • Tanzania / epidemiology
  • beta-Lactamases / genetics


  • Anti-Bacterial Agents
  • beta-Lactamases