DISCUSSION
infection
INFECTION, DISEASE
In this study, we found no evidence of an indirect effect of mass drug administration of azithromycin to younger children on respiratory pathogen carriage in older children, neither a reduction in pathogen prevalence nor pathogen quantity ∼6 months post the last treatment. In other words, this schedule of biannual azithromycin administration did not produce a measurable effect of nasopharyngeal carriage of bacterial respiratory pathogens among nontreated 7- to 11-year-old children.The ability of a drug to offer indirect protection is likely due to multiple factors such as the potency of the drug administered, pathogen and transmission pathways, baseline prevalence in the community, administration frequency, baseline resistance, average duration, frequency of infection, and sample collection time after drug administration. One potential explanation for this null finding is that younger children are not critical reservoirs for transmission of these respiratory pathogens to older children. Another possibility is that the intensity or duration of biannual azithromycin was not high enough to alter transmission in the community. Another possibility is that the time lag was too long between drug administration and nasopharyngeal testing to see an effect. For instance, it is known from children with invasive disease with The carriage prevalences were generally expected. In the Malawi site of MORDOR, a subset of the younger children were tested for The high rates of colonization of As for the molecular typing results, Niger currently vaccinates against Niger has also introduced the group A meningococcal conjugate vaccine (PsA-TT, MenAfriVac).In summary, there was no apparent reduction in 