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    ABSTRACT: Group A rotaviruses (RV) are the major cause of acute gastroenteritis in infants and young children globally. Waterborne transmission of RV and the presence of RV in water sources are of major public health importance. In this paper, we present the Global Waterborne Pathogen model for RV (GloWPa-Rota model) to estimate the global distribution of RV emissions to surface water. To our knowledge, this is the first model to do so. We review the literature to estimate three RV specific variables for the model: incidence, excretion rate and removal during wastewater treatment. We estimate total global RV emissions to be 2 × 10 18 viral particles/grid/year, of which 87% is produced by the urban population. Hotspot regions with high RV emissions are urban areas in densely populated parts of the world, such as Bangladesh and Nigeria, while low emissions are found in rural OPEN ACCESS Pathogens 2015, 4 230 areas in North Russia and the Australian desert. Even for industrialized regions with high population density and without tertiary treatment, such as the UK, substantial emissions are estimated. Modeling exercises like the one presented in this paper provide unique opportunities to further study these emissions to surface water, their sources and scenarios for improved management.
    06/2015; 4(2):229-255. DOI:10.3390/pathogens4020229
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    ABSTRACT: To assess public health risks of rotavirus via drinking water consumption, a cell culture-PCR assay was developed and optimized for the detection of infectious environmental rotavirus strains in naturally contaminated source waters for drinking water production. Infectious rotavirus concentrations were estimated by an optimized cell culture-PCR assay as most probable numbers by using the presence or absence of replicated virus in different sample volumes. Infectious rotavirus was detected in 11 of 12 source water samples in concentrations varying from 0.19 (0.01-0.87) to 8.3 (1.8-34.0) infectious PCR detectable units per litre (IPDU/l), which was not significantly different from the concentrations of infectious enterovirus in these samples. In 55% of the samples, rotavirus genomes were 1000 to 10 000 times (3 log(10)-4 log(10)) more abundantly present than infectious rotavirus particles, whereas in the remaining 45% of the samples, rotavirus genomes were less than 1000 times (<3 log(10)) more abundantly present. The broad variation observed in the ratios of rotavirus RNA and infectious particles demonstrates the importance of detecting infectious viruses instead of viral RNA for the purposes involving estimations of public health risks.
    Journal of Applied Microbiology 03/2009; 107(1):97-105. DOI:10.1111/j.1365-2672.2009.04184.x · 2.39 Impact Factor
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    ABSTRACT: Using genetically engineered lactobacilli, producing high avidity llama VHH domains (referred to as anti-rotavirus proteins; ARPs), to test the effect of multimeric antibody fragments as prophylaxis and therapy against rotavirus infection. Two ARPs, ARP1 and ARP3, shown to bind to different epitopes and act synergistically against rotavirus, were displayed on the surface of Lactobacillus paracasei as monovalent or bivalent proteins (mono- or bi-specific). Although a nonsignificant difference was observed between lactobacilli producing bispecific ARP3-ARP1 and monomeric ARPs, lactobacilli producing bispecific ARP3-ARP1 were superior at reducing the rate of diarrhea when used for prophylactic and therapeutic intervention in a mouse model of rotavirus infection in comparison to nontreated animals. Expression of bispecific antibodies in lactobacilli resulted in slight improvement of their efficacy. Furthermore, increasing the specificity would theoretically reduce the rate of appearance of viral escape mutants and would have a broader capacity to be effective against a range of viral serotypes.
    Future Microbiology 05/2011; 6(5):583-93. DOI:10.2217/fmb.11.32 · 3.82 Impact Factor