Evaluation of community directed vector control on transmission of Onchocerca volvulus in a Loa loa co-endemic region
This study will pilot the Slash and Clear methodology in an oncho-Loa loa co-endemic setting. Previous pilots in Uganda and Nigeria have demonstrated that this simple strategy of removing breeding sites can result in significant black fly reductions that last for several months. This study will provide important data on the impact of Slash and Clear on black fly biting, and consequently its impact on oncho elimination. Two intervention and one control community will be compared for two years, with repeated measurements being taken of biting rates.
Can geospatial algorithms be used by disease programs to help identify hotspots at community and Implementation Unit level?
Is the multiparallel quantitative polymerase chain reaction technique superior to Kato-Katz microscopy in assessing the intensity and prevalence of soil-transmitted helminth infections in stool?
Preliminary Findings and Lessons Learned
- qPCR was more sensitive than Kato-Katz at detecting Ascaris, Trichuris, and hookworm infections in child fecal samples.
- Very few samples were helminth positive by Kato-Katz microscopy that were not also positive by qPCR, suggesting minimal human classification error during microscopy.
- Duplicate qPCR analysis on ~10% of samples by two separate labs (Smith and KEMRI) showed excellent concordance (97-100% agreement for each helminth species).
- A reanalysis of the effect of a combined water, sanitation, and hand washing (WASH) intervention on child helminth infections with qPCR data compared to Kato-Katz data gave very similar results.
Analyze the relationships between the prevalence of the clinical sign follicular trachoma (TF) and the prevalence of infection and antibody to determine whether it may be appropriate to consider one or more alternative indicators for deciding whether trachoma programs can stop MDA.