Publications by authors named "Erick M O Muok"

Praziquantel alone is insufficient for the control of schistosomiasis due to poor efficacy against juvenile worms and increasing concerns about the risk of drug resistance. We compared the efficacy and safety of praziquantel combined with four different artemisinin-based combinations to praziquantel alone in treating infection in Kenyan children. In this randomized, open-label, five-arm, head-to-head, non-inferiority trial, children (aged 9-15 years) with infection according to duplicate Kato Katz thick smears from a stool sample in the Mwea irrigation scheme of central Kenya, were enrolled.

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Background: Reliance on praziquantel for the treatment and control of schistosomiasis is likely to facilitate the emergence of drug resistance. Combination therapy targeting adult and juvenile schistosome worms is urgently needed to improve praziquantel efficacy and delay the potential development of drug resistance. We assessed the efficacy and safety of single-dose praziquantel combined with single-dose artesunate plus sulfalene-pyrimethamine in the treatment of Kenyan children with schistosomiasis.

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Background: Globally, a fifth of the children continue to face chronic undernutrition with a majority of them situated in the Low- and Middle-Income Countries (LMIC). The rising numbers are attributed to aggravating factors like limited nutrition knowledge, poor feeding practices, seasonal food insecurity, and diseases. Interventions targeting behaviour change may reduce the devastating nutrition situation of children in the LMICs.

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Unlike praziquantel, artemisinin derivatives are effective against juvenile schistosome worms. We assessed the efficacy and safety of a single oral dose of artesunate plus sulfalene-pyrimethamine versus praziquantel in the treatment of Schistosoma mansoni. Seventy-three schoolchildren (aged 9-15 years) with confirmed S.

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Background: Schistosomiasis control relies on praziquantel for preventive chemotherapy. Alternative drugs are needed for the treatment and control of schistosomiasis. Praziquantel is effective against adult schistosome worms but ineffective against larval stages of the parasite and cannot prevent re-infection or interrupt the transmission of infection.

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Background: It has been proposed that childhood vaccines in high-mortality populations may have substantial impacts on mortality rates that are not explained by the prevention of targeted diseases, nor conversely by typical expected adverse reactions to the vaccines, and that these non-specific effects (NSEs) are generally more pronounced in females. The existence of these effects, and any implications for the development of vaccines and the design of vaccination programs to enhance safety, remain controversial. One area of controversy is the reported association of non-live vaccines with increased female mortality.

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Background: Climate change heavily affects child nutritional status in sub-Saharan Africa. Agricultural and dietary diversification are promising tools to balance agricultural yield losses and nutrient deficits in crops. However, rigorous impact evaluation of such adaptation strategies is lacking.

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Background: Among the different faces of immune reconstitution inflammatory syndrome (IRIS) developing in HIV-patients, no clinical definition has been reported for Schistosomiasis-IRIS (Schisto-IRIS). Although Schisto-IRIS remains largely uninvestigated, matrix metalloproteinases (MMP) and tissue inhibitors of metalloproteinases (TIMP) have previously been associated with S. mansoni infection and tuberculosis-IRIS.

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The potential consequences of parasitic infections on a person's immune responsiveness to unrelated antigens are often conjectured upon in relationship to allergic responses and autoimmune diseases. These considerations sometimes extend to whether parasitic infection of pregnant women can influence the outcomes of responses by their offspring to the immunizations administered during national Expanded Programs of Immunization. To provide additional data to these discussions, we have enrolled 99 close-to-term pregnant women in western Kenya and determined their and infection status.

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Previously, we have shown that persons with human immunodeficiency virus 1 (HIV-1) infection and reduced CD4(+) T-lymphocyte counts excrete significantly fewer Schistosoma mansoni eggs than HIV-1-negative persons with similar intensities of schistosome infections. To determine how antiretroviral therapy (ART) might affect egg excretion, we conducted a study of HIV+ adults living in an area highly endemic for S. mansoni as they began an ART program.

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Background: Schistosomiasis is an important parasitic disease in Kenya. Decreasing susceptibility of schistosomes to praziquantel, the major drug used to reduce disease morbidity, has made assessment of new antischistosomal drugs a priority. We aimed to assess the safety and efficacy of an artesunate-based combination drug in the treatment of schistosomiasis.

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Background: Age prevalence curves for areas in which schistosomiasis is endemic suggest that humans develop partial immunity to reinfection beginning in early adolescence. We conducted a 2-year longitudinal study to determine whether children infected with Schistosoma mansoni develop protection-related immune responses after treatment with praziquantel and whether the development of these immune responses is accelerated by frequent treatment after reinfection.

Methods: Children (8-10 years old) were tested for S.

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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) or harvesting sand (53 men) in Lake Victoria. Men were treated with praziquantel each time S.

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Flow cytometric analyses were performed to evaluate HLA-DR (+) activated T lymphocytes (Tact; CD3 (+)/CD4 (+)/CD25(medium)) and T regulatory cells (Treg; CD3 (+)/CD4(+)/CD25(high)) in the circulation of children 8-10 years of age living in an area endemic for both Plasmodium falciparum and Schistosoma mansoni in western Kenya. Those children with only S. mansoni had a higher mean percentage of HLA-DR (+) Tact than those who were co-infected with these two intravascular parasites.

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Schistosomiasis mansoni is usually a chronic infection that leads to long-term, systemic exposure to schistosome antigens. Experimental Schistosoma mansoni infection is associated with immunoregulatory mechanisms, including T regulatory cells (Treg) that may help control morbidity and dampen resistance to re-infection. We now show that some schistosomiasis mansoni patients have high proportions of CD3(+)/CD4(+)/CD25(high) Treg.

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