RESUMO
Novel methods are required to aid the monitoring of schistosomiasis control and elimination initiatives through mass drug administration. Portable digital and mobile phone microscopy is a promising tool for this purpose. This cross-sectional study evaluated the diagnostic operating characteristics of a converted mobile phone microscope (the SchistoScope) for the detection of Schistosoma haematobium eggs, as determined by community-based field workers and expert microscopists, compared with a field gold standard of light microscopy. Three hundred sixty-five urine samples were evaluated by conventional light microscopy, with 49 (13.4%) positive for S. haematobium. Compared with light microscopy, the sensitivity and specificity of S. haematobium detection by field microscopists trained to use the SchistoScope were 26.5% (95% CI: 14.9-41.1%) and 98.4% (95% CI: 96.3-99.5%), respectively. The sensitivity and specificity of S. haematobium detection by expert microscopists using the SchistoScope was 74% (95% CI: 59.7-85.4%) and 98.1% (95% CI: 95.9-99.3%), respectively, compared with light microscopy. The sensitivity rose to 96.1% and 100% when evaluating for egg counts greater than five and 10 eggs per 10 mL, respectively. A point-of-care circulating cathodic anion (POC CCA) test was used to evaluate Schistosoma mansoni; however, there were too few positive samples to reliably comment on diagnostic characteristics. This study demonstrated that a "urine-only" approach to rapidly screen for schistosomiasis at the point of sample collection can be conducted with mobile phone microscopy (S. haematobium) coupled with POC CCA (S. mansoni). Such an approach may aid in streamlined schistosomiasis control and elimination initiatives.
RESUMO
BACKGROUND: HIV postexposure prophylaxis-in-pocket ("PIP") is a self-initiated, event-driven HIV prevention modality for individuals with a low frequency of HIV exposures. METHODS: A cohort of 111 patients using PIP as their primary HIV prevention modality was longitudinally evaluated for PIP self-initiation, HIV and sexual transmitted infections, and switching to other HIV prevention modalities between February 2016 and December 2022. RESULTS: A total of 111 patients had 178.7 cumulative patient-years of PIP use. PIP was self-initiated 69 times by 35 (31.5%) individuals, with 0 HIV seroconversions identified. Thirty four individuals (30.6%) transitioned from PIP to pre-exposure prophylaxis and 33 individuals (29.7%) switched from pre-exposure prophylaxis to PIP. CONCLUSIONS: PIP is a useful addition to other pharmacologic HIV prevention tools, and may help prevent infection in those with a lower frequency of unanticipated HIV exposures.
