Diana M. S. Karanja

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Although accurate assessment of the prevalence of Schistosoma mansoni is important for the design and evaluation of control programs, the most widely used tools for diagnosis are limited by suboptimal sensitivity, slow turn-around-time, or inability to distinguish current from former infections. Recently, two tests that detect circulating cathodic antigen(More)
We evaluated a commercial point-of-care circulating cathodic antigen (POC-CCA) test for assessing Schistosoma mansoni infection prevalence in areas at risk. Overall, 4,405 school-age children in Cameroon, Côte d'Ivoire, Ethiopia, Kenya, and Uganda provided urine for POC-CCA testing and stool for Kato-Katz assays. By latent class analysis, one POC-CCA test(More)
BACKGROUND The near exclusive use of praziquantel (PZQ) for treatment of human schistosomiasis has raised concerns about the possible emergence of drug-resistant schistosomes. METHODOLOGY/PRINCIPAL FINDINGS We measured susceptibility to PZQ of isolates of Schistosoma mansoni obtained from patients from Kisumu, Kenya continuously exposed to infection as a(More)
BACKGROUND Previous studies suggest that humans can acquire immunity to reinfection with schistosomes, most probably due to immunologic mechanisms acquired after exposure to dying schistosome worms. METHODOLOGY/PRINCIPAL FINDINGS We followed longitudinally two cohorts of adult males occupationally exposed to Schistosoma mansoni by washing cars (120 men)(More)
BACKGROUND Previous studies have reported age-dependent development of resistance to reinfection by schistosomes and identified immunological correlates of this resistance. However, whether resistance exists that is independent of age effects has been questioned. We did a longitudinal investigation of reinfection by Schistosoma mansoni in an adult(More)
BACKGROUND The immunologic findings that most consistently correlate with resistance in human schistosomiasis are high levels of IgE and low levels of IgG4. We have genotyped gene and promoter polymorphisms of cytokines associated with regulation of these isotypes in a cohort of men occupationally exposed to Schistosoma mansoni in western Kenya and(More)
BACKGROUND Schistosomiasis, a parasitic disease that affects over 200 million people, can lead to significant morbidity and mortality; distribution of single dose preventative chemotherapy significantly reduces disease burden. Implementation of control programs is dictated by disease prevalence rates, which are determined by costly and labor intensive(More)
BACKGROUND The current reference test for the detection of S. mansoni in endemic areas is stool microscopy based on one or more Kato-Katz stool smears. However, stool microscopy has several shortcomings that greatly affect the efficacy of current schistosomiasis control programs. A highly specific multiplex real-time polymerase chain reaction (PCR)(More)
BACKGROUND The Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) was established in 2008 to answer strategic questions about schistosomiasis control. For programme managers, a high-priority question is: what are the most cost-effective strategies for delivering preventive chemotherapy (PCT) with praziquantel (PZQ)? This paper(More)
This study compared the effectiveness of the community-wide treatment and school-based treatment approaches in the control of Schistosoma mansoni infections in villages with ⩾25% prevalence in western Kenya. Stool samples from first year students, 9-12year olds and adults (20-55years) were analyzed by the Kato-Katz technique for S. mansoni eggs. After two(More)