Antibiotic Resistance in Young Children in Kilosa District, Tanzania 4 Years after Mass Distribution of Azithromycin for Trachoma Control.

Mass administration of azithromycin (MDA) is integral to trachoma control. Recent studies suggest that MDA may increase drug-resistant pathogens, yet findings from prior studies suggest little long-term impact on resistance. This disparity may be linked to differences in pre-MDA community-level resistance patterns. We describe carriage prevalence and antibiotic resistance patterns for Streptococcus pneumoniae (Spn) (nasopharyngeal swab collection), Staphylococcus aureus (SA) (nasopharyngeal swabs), and Escherichia coli (EC) (rectal swabs) in 1,047 children ages 1-59 months in a district with MDA cessation 4 years ago. Antibiotic susceptibility was evaluated by disk diffusion and Etest. The carriage rates for Spn, SA, and EC were 43.5% (455/1,047), 13.2% (138/1,047), and 61.7% (646/1,047), respectively. Resistance to AZM was observed in 14.3%, 29.0%, and 16.6% of the Spn, SA, and EC isolates, respectively. Spn resistance was variable (0-67%) by hamlet. Future analyses will assess the influence of pre-MDA antibiotic resistance patterns on those observed following MDA.

Corneal Sensitivity and Presence of Pathogenic Organisms Among Participants Who Have Undergone Trichiasis Surgery Differ by Surgical Outcome.

PURPOSE: To explore the potential association between reduced corneal sensation and/or conjunctival bacterial colonization and postoperative trichiasis and eyelid contour abnormalities after corrective eyelid surgery among participants with a history of trachomatous trichiasis. METHODS: As an ancillary study to the Partnership for Rapid Elimination of Trachoma (PRET) Surgery Trial in southern Tanzania, we collected data on 580 PRET participants who had undergone trichiasis surgery 1 year earlier and 200 age-group-matched individuals without trichiasis. Assessments included eyelid status evaluation (presence and severity of postoperative trichiasis and/or eyelid contour abnormality), corneal sensitivity by Cochet-Bonnet aesthesiometer, a questionnaire on symptoms of ocular irritation, and conjunctival microbiology. We divided PRET participants based on their eyelid status and compared results across PRET groups and versus normals. RESULTS: PRET participants had reduced corneal sensitivity compared with age-matched normals (mean sensitivity ranged from 2.8 to 3.8 cm in PRET participants vs. 5.9 cm in normals), and increasing severity of postoperative trichiasis was associated in a stepwise fashion with reduced corneal sensitivity (mean = 3.5 cm for mild and 2.6 cm for severe postoperative trichiasis). Conjunctival colonization with pathogenic bacteria was also associated with more severe postoperative trichiasis (Cochran-Armitage trend test P = 0.001) and with reduced corneal sensitivity (trend test P < 0.0001). Symptoms of ocular irritation were not associated with previous trichiasis surgery, postoperative trichiasis, or eyelid contour abnormality. CONCLUSIONS: These findings indicate that reduced corneal sensitivity accompanies trachomatous trichiasis and suggest that reduced corneal sensitivity may play an important role in the harboring of pathogenic bacteria on the ocular surface.

Mass distribution of azithromycin for trachoma control is associated with increased risk of azithromycin-resistant Streptococcus pneumoniae carriage in young children 6 months after treatment.

BACKGROUND: Emerging evidence suggests that the mass distribution of azithromycin for trachoma control (MDA) may increase circulation of macrolide resistance in bacteria associated with severe pediatric infections in treated communities. METHODS: We examined the effect of MDA on nasopharyngeal carriage of antibiotic-resistant Streptococcus pneumoniae among 1015 young children living in rural Tanzania. MDA with a single dose of oral azithromycin was provided in 4 of 8 communities where trachoma prevalence was ≥10%. Isolates were tested for susceptibility to azithromycin (AZM) and commonly used antibiotics by disk diffusion and Etest. We calculated the proportion of antibiotic-resistant S. pneumoniae carriage at baseline and again 1, 3, and 6 months after treatment, and at comparable intervals in the untreated villages. RESULTS: The proportion of AZM-resistant isolates was similar between groups at baseline (MDA: 35.8% vs non-MDA: 35.4%), however, this proportion was greater in the MDA group in all subsequent surveys. At 6 months, the percentage of AZM-resistant isolates was significantly higher in the MDA group (81.9% vs 46.9%, P < .001). The odds of AZM-resistant carriage was 5-fold greater in the MDA group (odds ratio, 4.95 [95% confidence interval, 3.23-7.61]). The proportion of isolates clinically resistant to AZM (minimum inhibitory concentration ≥16 µg/mL) was also significantly greater in the MDA group at 6 months (35.3% vs 12.4%, P < .006). CONCLUSIONS: Mass distribution of a single dose of oral azithromycin for trachoma was associated with increased circulation of macrolide-resistant S. pneumoniae carriage among young children in the 6 months following treatment. It is crucial that changes in antibiotic resistance patterns and their clinical significance in the treatment of severe pediatric infections be assessed in future MDA trials.